The hydraulic accumulator for water supply is designed not only to take part of the pressure on itself, it also performs some useful features and for heating. You should understand in a little more detail what the features of the hydraulic accumulator are, as well as how it is installed.
Purpose
Before moving on to the question of the purpose of the hydraulic accumulator, it is necessary to understand what it is. The hydraulic accumulator is a metal tank, inside of which there is an elastic cavity. Subsequently, the cavity can be filled with water. Thanks to the air gap located between the metal walls of the tank and the elastic cavity, the water “bag” never comes into contact with the metal.
Such a device gives the hydraulic accumulator many positive qualities.
First of all, the hydraulic accumulator allows you to partially remove the load from the pump. Before water is supplied directly by the pump, it is supplied from the accumulator. When the water level drops to a certain level, the pump turns on. Thus, the pumping unit is protected from water hammer.
Such measures can significantly increase the amount of time that the pump will serve. Such careful attitude will protect it from premature breakdowns and wear, while the quality of the pressure will not suffer. Even if you use two taps connected to the selected pumping station at the same time, the pressure will remain at the specified level.
Plumbing that runs from the same source will also last longer since it will not be subject to changes in water pressure. For example, washing machine pipes will not wear out as quickly. And an additional supply of water will allow you not to be afraid of interruptions in its supply, which is convenient if you live in a private house and the proper amount of water is always needed.
Functions
To sum it all up beneficial properties, which are provided by the presence of a hydraulic tank, its functions can be determined:
- Pump protection. The presence of a hydraulic accumulator helps protect the pumping system from unwanted influences and extend its service life. Due to the fact that the pump will only turn on when needed, it is guaranteed a certain number of unused starts. This refers to the deviation from the norm of starts per hour.
- Pressure support. Thanks to the fact that there is a hydraulic accumulator, you don’t have to worry about constant changes in water pressure. For example, if with only a pump there is a possibility that the water will flow either stronger or slower, especially when several taps are turned on at once, then with a hydraulic accumulator this problem disappears. After all, the load is divided into two technical devices, and not into one.
- Leveling water hammer. When you turn on the pump, you often encounter the fact that the water starts flowing too intensely. Such a sharp shock is called water hammer. Using a hydraulic accumulator allows you to avoid such problems, since water flows smoothly from the hydraulic tank. Thus, the pipeline will also last much longer.
- Providing a supply of water. If you live in an area that has water supply problems, you may benefit from having a hydro tank. It provides a certain supply of water suitable for domestic needs.
Depending on the need, you can choose a large hydraulic accumulator (up to 500 l) or a very small one (up to 5 l).
Design and principle of operation
The peculiarity of hydraulic tanks is that the water does not come into direct contact with the metal body, but remains enclosed in an elastic cavity, also called a membrane. The membrane is made of butyl, a durable rubber material. Butyl provides the proper level of protection of water from bacteria, which metal cannot boast of.
There is an air gap between the elastic membrane and the metal body. Nitrogen is pumped into it, but the chamber can also be filled with ordinary air. The chamber is equipped with a special pneumatic valve, through which the pressure inside is regulated. You can fill the chamber through this valve or, conversely, bleed the air.
The hydraulic accumulator installation can be disassembled and reassembled at any time. It has a simple device. This simplicity is ensured so that it is always possible to identify problems and carry out timely repairs. In this case, the device can be repaired without pouring all the water out of it.
Large-volume hydraulic accumulators have an additional valve in the membrane, which also allows air to be released, but here we are talking about air that is released from the water. Small hydraulic tanks do not have this function, but then the valve must be on the pipeline.
The hydraulic accumulator operates as follows.
- First, water is pumped into the elastic cavity, stretching and filling it. A special relay is attached to the cavity.
- Once the pressure threshold is reached, the relay reacts to this and turns off the pump.
- Further, during operation of the accumulator, the pressure drops again, and the relay, reacting to this, turns on the water again. The relay can be set to any level. This type of device is called an automatic hydraulic accumulator.
Nowadays, such options are practically not found, but there are still outdated hydraulic tanks, the level of filling of which must be monitored and filled independently as needed.
Types and selection criteria
There are many criteria based on which hydraulic tanks are divided. Each of them has its own characteristics that need to be taken into account during the selection process. One of these criteria is the material. If the expansion tank itself is made of stainless steel, then the membrane can be made of various types rubber:
- Natural. This is a natural rubber designed for drinking water. It stretches well, but this property can lead to the fact that over time water will penetrate through the walls of such a membrane. The natural rubber cavity can be filled with water at temperatures from -10 to +50 degrees.
- Butyl. This type of artificial rubber is also intended for drinking water. It fully complies with all safety requirements. It has less elasticity than natural, making it more durable. The temperature that butyl rubber can withstand is higher: from -10 to +99 degrees.
- EPDM. This type of rubber is also intended for storing drinking water. Like butyl, ethylene propylene rubber can withstand temperatures from -10 to +99 degrees, but fails somewhat faster than butyl.
- SBR. The brand is intended for process water. This water cannot be used for household needs, but it has found application in heating systems. Such hydraulic accumulators are used as expansion barrels for heating systems.
- Nitril. Perhaps the most unusual type, since it is intended for storing oils and fuel.
When choosing, be sure to pay attention to what type of rubber is used, since the last two types do not meet sanitary standards and are therefore not suitable for storing drinking water.
According to their configuration, hydraulic accumulators are divided into vertical and horizontal.
- Vertical. Vertical type hydraulic tanks are chosen mainly for rooms with a small area. Since they are extended upward and practically do not occupy usable area, they are an excellent choice for small home boiler rooms. The pneumatic valve is located at the top.
- Horizontal. Horizontal hydraulic accumulators are not so practical. In order to install them, you need to have a lot of free space. There is no valve or such constructs, so you have to make a special valve to bleed off the air.
The horizontal unit has a mount through which it is connected directly to the pump. Because of the possibility of fixing an external pump, they have gained such popularity.
Based on the type of storage, hydraulic accumulators are divided into mechanical and pneumatic.
Mechanical
For the operation of this type of storage device, the kinetic energy of a load or spring is required. These models are practically not used recently, since they have more disadvantages than advantages. Among the shortcomings, the most significant are:
- Large size. Such units take up a lot of free space, which is by no means related to their volume.
- Inertia. This refers to the ability of such systems not to change their original parameters regardless of external factors.
Sometimes adaptability is necessary. However, such hydraulic accumulators are cheaper.
Pneumatic
Today, such storage devices are more common, since functioning due to the influence of gas is simpler. This is exactly the device that was described in the previous sections. Devices from this category are divided into piston, pear or balloon and membrane.
- Piston. Devices of this type are extremely rarely used in domestic conditions. They are more suitable for industrial use. Their capacity is extremely high and reaches 600 liters. It is clear that few people constantly need such a volume of water at home. However, the cost of such installations is quite small.
- With a bulb or balloon. Such hydraulic accumulator tanks are not used alone. Most often they are part of a hydraulic pump system. IN in this case A bulb is fixed inside the metal tank. On one side there is a hole for filling it with water. It turns out that the pear is, as it were, stretched inside the metal tank. The air pumped into the container around the pear subsequently pushes out the water there. When the pressure drops, the bulb refills.
- Membrane. The principle of operation of a membrane accumulator is similar to the version with a pear, however, in this case, a silt rubber membrane acts as an elastic cavity. The membrane is connected to the metal body at only one end. When empty, the membrane is pressed against the outlet under the influence of the gas inside. When filled with water, the membrane expands.
According to their purpose, hydraulic accumulators can be divided into those suitable for heating systems, hot water supply and cold water.
- For heating systems. The hydraulic accumulator for heating serves to get rid of accumulated air in the pipes and also prevent the water temperature from decreasing.
- For hot water. Membrane expansion tanks are predominantly used to supply hot water. They are designed to compensate for the expansion of water that occurs due to temperature changes. This expansion results in pressure differences.
- For cold water. For cold water, hydraulic accumulators are mainly chosen, which are connected to an external source.
This solution is chosen mostly for private houses.
By size, tanks are divided into small and large.
- Small ones. These units do not have a large volume, but they are ideal for the home. Small devices include those with a volume of no more than 150 liters.
- Big ones. This may include industrial units, which take up a lot of space and are rarely installed within private homes. Basically, they are made horizontal. Their volume can be up to 600 liters. They are designed for storing process water.
Among other things, attention should be paid to those points that should radically influence the choice of a particular unit. Summarizing all of the above, we can highlight the following points that deserve special attention:
- Type. It is extremely important on what principle the accumulator operates. Each need requires a specific sample. So, for hot water, choose an expanding tank, and for cold water, choose a battery with the ability to supply water from a third-party source. When selecting a hydraulic accumulator tank for drinking water, pay attention to the presence of a filter. It is best to buy a hydraulic accumulator with a pneumatic accumulator.
- Volume. It is better to choose the tank capacity so that it completely covers the needs. For example, if you track how much water you spend in one shower, you can base your choice on this indicator.
- Orientation. It’s easiest to choose the configuration of the tank: if the room is small, then choose a vertical accumulator, but if the space allows, opt for the horizontal option.
Volume calculation
To make the volume calculation more accurate, it is recommended to use the following table. It shows the approximate supply of water that will be available after the pump stops pumping water due to a power outage. Please note that this indicator cannot be determined accurately, since it all depends on how the relay is configured.
In order to produce more accurate calculations, it is recommended to use a special formula: K (engine power factor) x Amax (limit flow liters per minute) x ((Pmax (pump switch-off pressure in bar) + 1) x (Pmin (pump switch-on pressure in bar) + 1)) / (Pmax – Pmin ) x (Pair (air pressure in the accumulator in bars) + 1).
For example, let's calculate from the table, taking random values.
With coefficient K = 0.25, maximum flow Amax = 2.1, and pressures Pmax = 3, Pmin = 1.8 and Pair = 1.6 we obtain: 0.25 x 2.1 x ((3 + 1) x (1.8 + 1)) / (3 – 1.8) x (1.6 + 1) = 31.41 l.
Installation steps
The installation of a hydraulic accumulator is carried out in several steps, completely different from those performed for an ordinary tank. . It should be taken into account that the hydraulic accumulator tank is practically never at rest. It works constantly, the membrane or bulb is constantly engaged and under pressure. Therefore, all installation and configuration steps must be carried out carefully and slowly.
First you need to fix the tank.
It must be securely fastened to the floor and not wobble. Rubber pads should be placed under the legs so that in the event of vibrations, noise, etc., the tank will be cushioned and will not wobble as much.
If this rule is neglected, during operation the metal case can swing and rattle violently, producing unpleasant sounds, as well as being subjected to unnecessary influences.
The pipeline must also be connected using rubber pads, which in this case perform an insulating function. It is important that the rubber adapters are flexible, otherwise they may crack and begin to leak water. In addition, flexible materials are easier to set up and operate.
It is optimal if the inlet of the accumulator and the connected pipeline have the same cross-section. Then there will be no additional connection problems. The cross-section of the wiring to the outlet must not be narrowed: this will lead to an unreasonable increase in pressure in the accumulator tank, which can cause a streak, since tanks are often not designed for this.
Before first use, the tank must be properly prepared. First of all, the membrane or bulb is checked for the presence of air. If there is air, it is vented. Next, the tank is filled with water under very low pressure. This is due to the fact that rubber, when caked, sticks together, and if it is pulled apart too sharply, it can be damaged or torn. To prevent this from happening, filling must be done slowly and carefully.
When choosing a location for operation, it is necessary to ensure free access to the mechanism from any side. In general, it is best to entrust the connection of a hydraulic accumulator tank in a water supply system to experienced specialists, since due to inexperience it is possible not to take into account some non-obvious, but important factors, such as pressure drop or mismatch in the cross-section of water pipes. Such risks are unacceptable, since the hydraulic accumulator is a rather expensive unit, and repairs plumbing system will cost you a pretty penny.
If you decide to take a risk and do everything yourself, use the following step-by-step instructions.
Adjustment
After the tank has been purchased and brought home, the first thing you need to do is check the pressure inside it. Usually it is 1.5 bar, but often the pressure drops due to leaks due to long storage. The pressure is checked using a pressure gauge.
You can check it while you are in the store. Then, right at the time of purchase, ask the sales consultant to take the necessary measurements. The accuracy of the pressure gauge offered in the store is usually high enough so that the error does not greatly affect the final result of the changes.
Experts usually recommend setting a pressure that will be 10% lower than in the membrane when the pump is turned on. To adjust the level, pump up the air chamber or bleed off excess air. However, it is worth keeping in mind that pressure drops have an extremely negative effect on the service life of the membrane. If the difference is more than 1.5 bars, this will increase the load.
T Also, the pressure should be set taking into account what exactly you need the tank for. For example, some people like to take powerful showers or use hydromassage. Then the pressure in the air chamber should be slightly higher than if you only want to take a bath. However, the pressure in the air chamber should not be too high, otherwise you simply will not be able to pump water into the membrane. Too little pressure is also detrimental: the membranes are not designed for an increased volume of water.
Relay settings
After the hydraulic accumulator has been adjusted, they proceed to adjusting the relay responsible for turning the pumping station on and off.
To make the settings correctly, do the following:
- Open the cover of the compartment containing the relay.
- Take a look at what this relay consists of. You will see two springs and nuts. We denote the large spring and nut as P, and the small ones as delta P.
- First, understand the components responsible for turning on the pump. This is group P. To make the spring more responsive to pressure, tighten the large nut a little.
- The delta P group is responsible for turning off the pump. By pulling it up, you will indicate that the pump is turned off at a time when the membrane is not yet completely filled with water.
After you have made the settings, test what happened. If you are not very happy with the result, tighten or loosen the nuts again.
During tests, it is not necessary to close the relay with a lid, however, after setting all the settings, the lid must be closed.
Filling with water
After the pressure inside the accumulator is set and the relay is configured, you can proceed directly to filling the hydraulic tank. Here again you will need a high-quality pressure gauge with a detailed scale of values and low accuracy. It is necessary to connect it to the tank and fill it with water, strictly observing the values.
Arm yourself with the technical characteristics of your tank. They indicate what pressure can be considered normal and what is the maximum. If the pressure gauge readings approach the limit, immediately stop the water flow and try to equalize the pressure by bleeding or adding air to the air chamber.
When filling the accumulator tank, you must manually turn off the pump at the moment when the pressure becomes optimal. After this, the relay is adjusted according to the desired parameters by loosening or tightening the small spring. Keep in mind that a pressure of 3 bar is sufficient, although you can vary it as you wish. The difference between the pressure to turn the pump on and off should be about 1-1.5 bar. As practice shows, this is quite enough.
Having completed all of the above steps, you can safely begin the full operation of your hydraulic accumulator. Every couple of months, check the pressure in it, inspect the relays and joints with the plumbing system, and also monitor the operation of the pump.
The connection diagram shown here is not the only one. There are several more options that have found application in domestic conditions.
Scheme: options
First of all, the scheme for connecting a hydraulic accumulator to a pumping station depends on the functions that are superimposed on it, as well as on the method of using the hydraulic tank itself. The most popular options include the following.
Piping of the booster pumping station
Installing a hydraulic accumulator in a similar way appropriate when there is a large volume of water consumption. At such pumping stations, one pump is always running continuously, which can cause large pressure surges that need to be addressed immediately.
Here the hydraulic tank dampens pressure surges, thereby extending the service life of all pumps. It also compensates for small fluctuations in pressure that can occur due to the large volume of water consumed.
However, the scope of application of this type of connection does not end there.
It happens that power outages occur constantly, and the availability of water is vital. Similar situations can arise at agricultural sites, for example. Here, a water reserve helps to survive such periods of crisis, often lasting several days.
The hydraulic accumulator plays the role of a damper here. The more powerful pumping station, the larger the volume the hydraulic tank must have and the greater the pressure it must cope with. Otherwise, the desired effect will not be achieved.
For submersible pump
In order for the submersible pump not to run idle, it is necessary that it only performs from 5 to 20 starts per hour, which is described in detail in its technical characteristics. If the pressure in the water supply system drops, the pump will turn on automatically. Such falls can occur much more often than 20 times per hour. To compensate for such differences, a hydraulic tank is needed.
In this case, the hydraulic accumulator is designed to compensate for the small water flow, which also leads to the pump being turned on, thereby preventing the submersible unit from being turned on in a stupid way. The accumulator relay is not as sensitive as that of a submersible pump. In addition, the pump supplies water in sharp bursts and instantly, causing the pressure to jump sharply. This has a negative effect on the pipes. Connecting a hydraulic tank also eliminates this problem.
There is no need for a large hydraulic tank here. To choose the optimal volume, it is necessary to evaluate how much water is consumed per hour, how often the pump is turned on, and pumping power. An important role is played by where the tank will be installed relative to the pump and at what height the pump itself is mounted.
With storage water heater
If you connect a hydraulic tank to a water heater, it will be used as an expansion tank without reacting to changes in water temperature. Since the water in the water heater rises under the influence of expansion, the elements of the water heater, which are not always designed for such loads contrary to their intended purpose, may become damaged, which will result in the need for a complete replacement of this expensive equipment.
The membrane in the hydraulic tank can easily withstand the expansion that the water undergoes. The cavity is elastic and cannot be damaged by a slight expansion of volume.
In this regard, connecting a hydraulic tank to a water heater is a good idea, allowing you to keep the water heater itself safe and sound.
In front of the pumps in the direction of water movement
In this case, the hydraulic accumulator is connected to the circuit before the control pump. It is needed so that the pressure does not drop so sharply immediately after turning on the water and the pressure remains at the same level. The volume of the hydraulic tank plays a special role here. So, the more water is consumed, the higher the capacity must be, otherwise all measures to install the hydraulic accumulator will be useless and pressure compensation will not be achieved.
Connection
The hydraulic tank is included in the circuit in the place where it can provide the greatest return. The exact connection locations are marked in the drawings above. Depending on the problem you are facing, the location of the accumulator and its volume will vary.
Examination
The hydraulic accumulator is checked in order to identify membrane faults and timely replacement of this important component. Today there are many videos and instructions on how to carry out the test yourself at home. Below is the simplest of instructions.
To begin with, there are several preventive measures designed to ensure uninterrupted operation of the membrane cavity. There are also signs that clearly indicate that there is something wrong with the hydraulic tank. These include the following:
- Monthly blood pressure check. It is important that the existing parameter and those specified in technical passport hydraulic accumulators coincided. If this is not the case, we can say that there is some kind of problem.
- Presence of rust on the body. If the membrane were intact, then water would not get on the body and corrosion would not form on it. On the other hand, this may be due to the fact that water entered the housing from the outside. For example, the hydraulic tank is located under a pipe with hot water, condensate from the pipe systematically drips into the same place on the surface.
- Humidity at joints. This may also indicate that the membrane has burst and is leaking water. Protruding drops cannot appear in a cavity, which in theory is filled only with air or gas, just like that.
- Strange sounds. Because the pump is running, it is almost impossible to hear any sound from the hydraulic tank. If there are sounds and they are quite distinct, then this may be a sign of a serious breakdown. If you have just connected the accumulator and it is still under warranty, it is recommended that you return it immediately.
- Visible damage. Armed with a flashlight, you should inspect the membrane in advance for any damage visible to the eye: holes, cracks, cracks. They shouldn't exist. If such defects exist, replace the membrane.
Checking the initial pressure has already been given in one of the previous sections, so it makes sense to briefly describe the procedure:
- the tank must be disconnected from the pumping station;
- then the water in it is released from the hydraulic tank;
- By connecting a pressure gauge, the level of air pressure in the accumulator is checked.
Possible faults
During the operation of a hydraulic accumulator, many problems can arise, and you need to know how to fix each problem. To do this, you need to take into account the reasons that may lead to such troubles.
- In case of malfunctions pumping unit when it turns on and off frequently, the problem may be with the membrane. In this case, it is recommended to test its integrity and, if necessary, replace it with a new one, having first thoroughly dried the metal body of the tank.
- The occurrence of a leak near the pneumatic valve, through which air can be released or the tank can be filled, is also associated with a violation of the integrity of the membrane. As in the previous case, the membrane needs to be replaced.
- For too low pressure there may be several reasons for the valve. The simplest thing is insufficient thickness air gap. In this case, you just need to add a little air inside the hydraulic tank. The second reason is more serious. If the part through which air escapes is broken, you will have to replace it. Welding may be required.
- A leak in the pipe that comes from the pump may occur due to loss of tightness. In this case, you should try to tighten the flange a little tighter so that it fits more tightly. If this does not help, it is recommended to completely replace the parts.
- If the pressure in the tap is uneven, despite the presence of a hydraulic tank, then the problem may be in the elastic cavity. Carry out a full inspection of it, test it several times. If you still have doubts about its tightness, then replace the existing part with a new one.
- Low pressure is not due to the membrane, but to the fact that your pump may not work correctly or may even be faulty. Be sure to check the pump for functionality. Repair it if a problem is found. The second reason may be the wrong choice of accumulator volume. In this case, there is only one way - replacing the hydraulic tank with a suitable one.
If liquid comes from the pneumatic valve or forms near it, this means that with one hundred percent probability the membrane will have to be replaced.
Expert opinion on the need
Below is a video in which a specialist clearly substantiates the need to purchase a hydraulic accumulator. He states that the hydraulic tank is one of the the best ways level the excessive load on the pumps, thereby significantly extending their service life.
Hydraulic tanks in individual water supply systems perform several functions at once: important functions. In order for them all to work properly, it is important to choose this unit correctly, taking into account a variety of initial data. For example, maximum flow water when using several devices simultaneously, the recommended number of pump starts per hour and others.
Therefore, every owner should know which hydraulic accumulator is best to choose for water supply systems. country house. We will talk about the selection parameters based on the design and operating principle of this device below.
Why do you need a hydraulic accumulator?
There are several reasons that force us to use a hydraulic accumulator for autonomous source using a pump. Or rather, no one can force you, but this device provides many advantages, and it would be stupid not to take advantage of them.
Among them:
- The ability to maintain water pressure in the system at a certain level even when the pump is not working;
- The ability to accumulate a certain volume of liquid and use it in the event of a power outage or pump breakdown;
- Possibility to extinguish overpressure in the water supply system and prevent the destructive consequences of water hammer (see);
- The ability to prevent the pump from turning on every time the water tap is opened.
Please note. Any pump is designed for a certain number of on and off cycles per unit of time. If there are more such cycles, the equipment will quickly exhaust its resource and fail. And the hydraulic tank reduces the number of cycles, thereby extending the life of the pump.
What you need to know about the features of the hydraulic accumulator
In order for the water supply to operate normally and stably, calculating the volume of the hydraulic accumulator is one of the first tasks. Knowledge of what this unit is, how it functions and how to configure it to optimal mode helps to solve it correctly.
Design
This is a metal tank, inside of which there is a rubber balloon (bulb) in which water is accumulated. Air is pumped between the walls of the tank and the cylinder.
Please note. In some models, the cylinder is replaced by a diaphragm (membrane), dividing the internal volume of the tank into two cavities - air and water.
The hydraulic tank is equipped with a filter and outlets for water and air. As a rule, the fitting for connecting to the water supply is placed in the lower part of the container, and the spool with a nipple for inflating or bleeding air is in the upper part. But other design options are also possible.
There is no fundamental difference between these two designs. The only thing you should pay attention to when choosing is the possibility of replacing the inner membrane with your own hands if it wears out.
In this regard, a tank with a rubber bulb is preferable. To change it, just remove the flange that holds the cylinder in the metal casing.
Purpose
Such tanks are installed not only in water supply systems. They are also used in autonomous heat supply from a boiler with a pump (see).
It is important to know that tanks for thermal systems are painted red, and for water tanks mainly blue, but there may be other options - green, chrome-plated.
What is the difference between them:
- The expansion tank for heating mains contains a membrane made of technical rubber that can withstand high temperatures. The design is usually non-removable, so if the internal tank is damaged, the entire tank has to be replaced.
- The cylinder in hydraulic water tanks is made of food-grade rubber that does not negative influence on the taste and properties of drinking water. The design can be either with a removable or a fixed membrane.
For reference. Tanks with a fixed membrane are cheaper and have a greater margin of safety, but if defects appear on the rubber, they must be replaced. Whereas hydraulic accumulators with a replaceable membrane or cylinder are more expensive, but if they are damaged, it is enough to change only the internal tank.
Inner tank material
Food grade rubber, as a material for making a membrane, can also be different and differ in composition, resistance to high or low temperatures, and durability.
- Natural rubber very elastic, but has low resistance to water diffusion. It can withstand temperatures from 0 to +50 degrees.
- Artificial butyl rubber less elastic, but more durable. Operating temperature range from -10 to +100 degrees.
- Artificial ethylene propylene rubber the most durable and reliable. If the instructions for the accumulator contain information that the membrane is made of food-grade EPDM rubber, then you can be sure that it will last a long time even with very intensive use. Critical operating temperatures are -50 and +130 degrees.
Tank volume is the main selection criterion
Most important question– how to choose the volume of a hydraulic accumulator for water supply systems. To answer it, you need to bring together a lot of data. This includes the performance of the pump, the equipment of the house with water-consuming equipment, the number of people permanently living in the house, and much more.
But first of all, you need to decide whether you need this reservoir only to stabilize the operation of the system as a whole, or whether there is a need for a supply of water in case of a power outage.
If the house is small and equipped only with a washbasin, toilet, shower and watering tap, and you do not live in it all the time, you don’t have to make complex calculations. It is enough to buy a tank with a volume of 24-50 liters, it will be enough for the system to work normally and be protected from water hammer.
In the case of country house For permanent residence family, equipped with everything necessary for a comfortable life, it is advisable to approach the issue more responsibly. Here are a few ways you can decide on the size of your accumulator.
According to pump characteristics
The parameters that influence the choice of tank volume are the performance and power of the pump, as well as the recommended number of on/off cycles.
- The higher the power of the unit, the larger the volume of the hydraulic tank should be.
- The powerful pump pumps water quickly and turns off quickly if the tank volume is small.
- A sufficient volume will reduce the number of intermittent starts, thereby extending the service life of the electric motor.
To calculate, you will need to determine the approximate water consumption per hour. To do this, a table is compiled that lists all devices that consume water, their quantity and consumption rates. For example:
Since it is almost impossible to use all devices at the same time, a correction factor of 0.5 is used to determine the actual flow rate. As a result, we get that you spend an average of 75 liters of water per minute.
- Let's say the productivity is 80 l/min or 4800 l/h.
- And during peak hours you need 4500 l/h.
- When the pump operates non-stop, its power is quite sufficient, but it is unlikely to work for a long time in such conditions. extreme conditions. And if it turns on more than 20-30 times per hour, its resource will run out even faster.
- That’s why we need a hydraulic tank, the volume of which will allow us to turn off the equipment and give it a break. At the indicated cycle frequency, the water supply should be at least 70-80 liters. This will allow the pump to remain idle for one minute out of every two, pre-filling the reservoir.
This is important! Keep in mind that the total volume of the accumulator and the maximum volume of water in it are far from equal. Water takes up only about a third internal space reservoir.
To use this formula, you need to know the settings of the pressure switch, which turns the pump on and off. The following picture will help you understand:
- 1 – initial pressure Pair (with the pump turned off);
- 2 – water flow into the tank when the pump is turned on;
- 3 – reaching the maximum pressure Pmax and turning off the pump;
- 4 – water flow with the pump turned off. When the pressure reaches the minimum Pmin, the pump turns on.
The formula looks like this:
- V = K x A x ((Pmax+1) x (Pmin +1)) / (Pmax - Pmin) x (Pair + 1), where
- A is the estimated water flow (l/min);
- K – correction factor from the table, determined depending on the pump power.
You must set the values of the minimum (starting) and maximum (switching off) pressure on the relay yourself, depending on what pressure you need in the system. It is determined by the farthest and highest water collection point from the accumulator.
Advice. The difference between the maximum and minimum values should be 1-1.5 atm. And the initial pressure Pair should be 10-20% less than Pmin.
To adjust the pressure switch, you need to know how to inflate a hydraulic accumulator for water supply systems with air, or bleed off excess air. To do this, you will need a car pump, which is connected to the tank through a spool.
Now you can calculate the volume. For example, let's take:
- A = 75 l/min;
- Pump power 1.5 kW, respectively K = 0.25;
- Pmax = 4.0 bar;
- Pmin = 2.5 bar;
- Pair = 2.3 bar.
We get V = 66.3 liters. The nearest standard hydraulic accumulators in terms of volume have a volume of 60 and 80 liters. We choose the one that is larger.
Shape, dimensions
Perhaps the shape of the tank may matter to you - vertical or horizontal. For example, if the space for its installation is limited in area or height.
In addition, when using a large-volume tank, make sure in advance that its dimensions will easily fit into the doorway or choose another model. This is not difficult to do, since the choice of hydraulic accumulators from different manufacturers on our market is quite large.
Conclusion
Now you have an idea of how to choose a hydraulic accumulator for water supply systems. The video in this article will also help you produce necessary calculations and decide. If you do not want to delve deeply into this issue, or you do not rely on your own knowledge, contact a water supply specialist.
A hydraulic accumulator, also known as a storage, pressure or expansion tank, is a necessary element for a closed water supply system in any private home. In order to correctly select and use such an accumulator, it does not hurt to study the principle of operation of the hydraulic accumulator, the types, causes of breakdowns and how to eliminate them. In addition, it doesn’t hurt to figure out how the red and red tanks differ. blue.
How does a hydraulic accumulator work?
Hydraulic accumulators are often called hydraulic accumulators, since inside such a device there is a special rubber gasket- membrane. It divides the container into two parts. On one side of the membrane there is water, on the other there is air or intervening gas. Also, the hydraulic tank is usually equipped with a hole for water supply and a pressure gauge that reflects air pressure.
Typically the hydraulic tank consists of metal case and rubber membrane. In addition, a spool is installed that regulates the air supply and bleed, as well as a filter to remove small contaminants
Water is supplied to the water supply system using a pump and pumped into the tank. As a result, the gas pressure in the automatic accumulator increases. When it reaches the maximum permissible value, the system automatic control turns off the pump and the water supply stops.
The diagram clearly shows the principle of operation of a hydraulic tank in a water supply system. The device is controlled automatically, which increases its service life
Gradually, the water from the tank is consumed. The pressure decreases, reaches the minimum specified limit, after which the automatic control system turns on the pump. Water enters the tank until the pressure reaches the set value, the pump turns off, etc.
Why is such a drive needed?
If there is a hydraulic tank, the pump on-off cycle occurs only when it is necessary to fill the tank with a sufficient supply of water. If there were no hydraulic accumulator, the pump would turn on every time one of the household members opens the tap. Availability storage tank in the system allows:
- significantly increase the service life of the well pump;
- prevent harm from possible water hammer in the system;
- maintain a certain pressure in the system;
- prevent breakdowns of elements of the water supply system and plumbing equipment.
It is obvious that hydraulic accumulators for water supply closed type simply necessary. The role of the storage tank in the water supply system is described in detail in the following video:
Types of membrane tanks and their features
There are vertical and horizontal hydraulic tanks, which are mounted differently at the installation site. There's another one important point. In the part of the hydraulic tank that contains water, a small amount of air can accumulate over time. This air should be periodically removed so that quite dangerous substances do not enter the system. air jams. In vertical containers, air accumulates at the top and a special nipple is used to remove it.
With horizontal hydraulic tanks everything is somewhat more complicated. To bleed off accumulated air, you will need not only a nipple, but also a ball valve, as well as a sewer drain.
Owners of small hydraulic tanks with a capacity of less than 100 liters need to get rid of excess air differently. To do this you should:
- Turn off power.
- Open the mixer tap.
- Wait until the tank is empty.
- Close the tap.
- Connect the system to power to refill the tank.
Excess air will escape along with the water. This procedure should be done at least once a month.
Red hydraulic tanks are designed for hot water supply systems. Although the membrane in them is made of fairly durable rubber, they should not be used to supply cold water
Manufacturers offer hydraulic tanks in red and blue, as well as colorless ones. Blue devices are intended for use in a cold water supply system. To make the membrane in such tanks, food grade rubber is used, which is safe for human health. Red hydraulic tanks are intended for heating and hot water supply systems. It is not recommended to use them for cold water, since the membrane in such tanks is made of a different rubber. In addition, the operating pressure threshold for blue hydraulic tanks is higher and reaches 8 Bar.
Typically, water enters the storage tank from below, and on top, as already noted, there is a nipple through which air is discharged. Therefore, each device has two threaded connections(usually inch or half inch), which should not be confused. They are often installed on the upper nipple automatic device for air removal.
Sometimes there are situations when water is supplied to the hydraulic tank from above. It is believed that in this case automatic air venting will not be needed. But you should take care of the filter so that sand particles or other contaminants do not enter the system.
Pay attention! The consumer is offered a wide variety of models of hydraulic tanks of foreign and domestic production. Not all imported devices are adapted for the Russian water supply system, which significantly reduces the period of their uninterrupted operation. As practice has shown, domestic hydraulic tanks high quality last longer.
Pay attention to the material about the design and operating principles of pumping stations:
Causes of breakdowns and ways to eliminate them
The most vulnerable part of the hydraulic tank is the rubber membrane. During operation, it is constantly stretched and then contracts. Gradually, the rubber loses its elasticity and breaks. The following symptoms may indicate problems with the hydraulic tank:
water comes from the system in small portions when high blood pressure, the tap seems to be “spitting” water;
the pressure gauge needle suddenly reaches high values and then immediately drops to zero.
Rubber membranes for hydraulic tanks can have different shapes and sizes. When replacing the membrane, use a product designed for a specific hydraulic tank model
To make sure that the membrane is torn, you need to press the nipple spool to release air from the storage tank and determine what air pressure is in the accumulator. If at the same time the pressure gauge needle immediately goes down, it means that there is very little air left in the hydraulic tank that provides the necessary pressure. It is necessary to completely bleed the air, if after this water flows from the spool, then the membrane is definitely torn and repairs are necessary. If the water does not flow, the membrane is intact, and the air leaves the container through the cracks that have appeared, faulty connections or the spool.
Problems with the hydraulic tank in the hot water supply system can be indicated by a small leak that appears at the water heater safety valve. You should proceed in exactly the same way: press the spool valve nipple, estimate the amount of air, bleed it completely and determine by the presence or absence of water whether the hydraulic tank membrane is intact.
Replacing the membrane in a hydraulic tank is not that difficult; in addition, it is much cheaper than installing a new device. For repair you will need:
- Purchase a new membrane that exactly matches the torn one.
- Carefully disassemble the hydraulic tank by unscrewing the connecting bolts.
- Remove the torn membrane.
- Install a new membrane in its place.
- Assemble the hydraulic tank.
- Tighten all bolts evenly.
The main danger in this case is that improper handling of the device can lead to the edge of the membrane slipping into the metal case. As a result, the work will have to be redone. To prevent this from happening, it is recommended to tighten the connecting bolts gradually to ensure even tension on the membrane. Problems arise when one bolt is fully tightened before working on the next one. At the same time, the edge of the membrane shifts and can slide off.
You will learn about common malfunctions and how to fix them in our material:
Another mistake is using sealant at joints. The use of such compounds leads to a reduction in friction between rubber and metal. As a result, the edge of the membrane moves and the joint density decreases, which can cause water leakage in the future.
Often homeowners are faced with the problem of a sharp increase in pressure (jumps) of cold water in private sectors. You can turn a blind eye to this if the owner is not interested in anything other than the water supply. But when a washing machine or dishwasher is installed in the house, this will become a problem. In this case, hydraulic accumulators for water supply systems, which stabilize the pressure, save household appliances from breakdowns. Some models are spacious and allow you to use water for some time after the supply has stopped, which is not uncommon in the private sector. Today we’ll talk about the types of storage tanks for water supply, connection diagrams, and also find out which manufacturing companies offer such products on Russian markets.
Read the article:
What is a hydraulic accumulator: the role of the unit in water supply
A hydraulic accumulator, also called a hydraulic tank or membrane tank, is a water reservoir included in the water supply system. Inside there is a membrane on which air presses, which allows you to turn the pump on and off as needed. Why is it installed?
Why do you need a hydraulic accumulator in cold water supply and hot water supply?
The hydraulic tank performs several functions:
- maintaining water pressure at a given level (adjustable);
- protection against pressure surges;
- increasing the service life of the water pump, turning it off periodically;
- protection of water supply system components from water hammer;
- increase in service life household appliances, connected to the cold water supply system;
- the ability to use the water supply for some time after the supply is cut off.
Regardless of whether the water supply system of a private home is subject to pressure drops or water hammer, such a device will not be superfluous in the scheme. After all, prevent emergency situation easier than eliminating its consequences.
Construction of hydraulic accumulators for water supply to private houses
This unit consists of two parts - the hydraulic tank itself and a membrane that divides its internal volume into 2 sections, one of which is filled with water and the other with air. Hydraulic tanks of 100 liters or more are equipped with a valve through which air accumulated in the water is released. Smaller devices are equipped with a special valve or tap for these purposes.
The membrane for the hydraulic accumulator is made of butyl - a special rubberized material that is resistant to bacterial influences and meets all the requirements of sanitary and epidemiological standards.
The principle of operation of a hydraulic accumulator in a water supply system
The operating algorithm of such devices is divided into four stages:
- Water supply by pump to the inner membrane.
- When the required pressure is reached, turn off the pump and stop the water supply.
- When the taps are opened, the flow from the tank is shown when the pump is turned off.
- A decrease in pressure in the tank causes the membrane to bend in the opposite direction, and the pump turns on again.
The pressure switch, as well as the amount of air pressing on the membrane, can be adjusted within the range specified by the manufacturer.
Related article:
In the publication we will look at what it is, scope of application, design features, principle of operation, advantages and disadvantages, selection criteria, models and manufacturers, do-it-yourself installation.
Good to know! The larger the storage capacity, the wider the range of settings. Large tanks allow you to turn on the pump less often, which increases its durability.
Hydraulic accumulators need to be serviced periodically. The fact is that the air supplied with water accumulates inside, which leads to a decrease in the performance of the tank. Once every 2-3 months, the accumulated air is released through a special tap or valve (if automatic release is not provided). Hydraulic tanks with automation require only visual inspection and checking for leaks every six months. Air pressure is adjusted as needed.
Types of hydraulic water tanks: separation by location and other parameters
Let's present this section in tabular form for ease of understanding:
| Separation | Designation | Peculiarities |
|---|---|---|
| Location type | Horizontal | The volume of such tanks is larger. The vertical position allows the installation of an air bleed valve from above. This makes maintenance easier. The only limitation in installation is the volume of the room. |
| Vertical | Compact options in which a tap is installed to vent air. The disadvantage is that in some models you have to completely drain the water to bleed the air, which is not economical. | |
| Energy storage | Pneumatic accumulation | Diaphragm, balloon or piston. The problem arises when the partition wears out - expensive and labor-intensive repairs are required. |
| Balloon or pear | Most popular. When worn out, the pear is replaced with a new one independently, without the involvement of professionals. | |
| Mechanical storage | Weight or spring. Work is based on kinetic energy. Quite voluminous and work autonomously. |
How to choose a hydraulic accumulator for water supply systems of a private house
Before purchasing, you should consider all the parameters of the hydraulic tank. Special attention worth paying attention to:
- tank volume;
- type of location;
- type of energy storage;
- nominal pressure;
- cost of the selected model.
When purchasing, you should ask your sales consultant about the availability and cost of replacement membranes or cylinders for the selected model and how accessible they are in principle. It would be useful to check the accompanying documentation and certificate of conformity, as well as clarify the warranty period for the device.
Related article:
: what it is, device and principle of operation, types, how installation is performed, review of models, average prices, useful tips and recommendations – read our review.
Important information! If planned self installation, you need to find out if this is a reason to void the warranty. Some manufacturers oblige buyers to hire professional installers - this is prescribed as one of the clauses of the warranty service agreement.
It is quite difficult to understand the range of such products. Today on store shelves there are products various companies. In order to help the reader, we will consider the most famous and popular among the population.
Which company is better to buy a hydraulic accumulator for water supply systems?
As an example, we present the 5 most famous and popular brands (one model from each manufacturer) with some technical characteristics.
| Make, model | Tank volume, l | Operating water temperature, ˚С (max) | Pressure, atm. (max) | Dimensions (VShG), mm |
|---|---|---|---|---|
| 80 | 99 | 8 | 480×460×600 | |
| 20 | 99 | 10 | 492×250×250 | |
| 12 | 70 | 10 | 310×280×280 | |
| Stout | 50 | 100 | 10 | 770×382×382 |
| 24 | 90 | 6 | 290x265x265 |
The 50 and 100 liter Gilex hydraulic accumulator models are very popular. They are made from high-strength steel, which ensures reliability and durability. Here's what netizens say about this brand.
MarEvo512, Russia, Moscow: Last week we had to replace an old hydraulic accumulator that had worked for eleven years with the exact same model. The Gilex brand hydraulic accumulator is a metal tank with a volume of 50 liters with horizontal installation... I can confidently recommend such a hydraulic accumulator, because 11 years of impeccable year-round operation gives me the right to do so, although the manufacturer plays it safe and gives a service life that is half as long. I rate the Gilex hydraulic accumulator “excellent” and have no doubt that it will work for many years, like its predecessor...
More details on Otzovik: https://otzovik.com/review_5225199.html
We calculate the required volume of the hydraulic accumulator for the water supply system
The volume of the accumulator depends on the number of consumption points (shower, sink, toilet), as well as on the number of residents (a secondary indicator). It is worth considering the power (type) of the pump.
| Pump | Power, W | Location | Hydraulic accumulator tank volume, l | |
|---|---|---|---|---|
| Type | Surface | ≤ 1000 | Horizontal | 24 |
| ≥1000 | Horizontal | 50 | ||
| Submersible | ≤500 | 24 | ||
| 500-1000 | Horizontal or vertical | 50 | ||
| 1000-1500 | Horizontal or vertical | 100 | ||
Stages of installing a hydraulic accumulator for do-it-yourself water supply systems
The installation of the purchased hydraulic accumulator is carried out in several stages. The first thing to do is check the pressure in the air chamber. This is done simply, using car pump or a compressor equipped with a pressure gauge. The pressure is made slightly greater than the value at which the pump turns on. The upper level is set with a relay and is set one atmosphere above the primary level.
Selecting a hydraulic tank connection diagram
The most convenient connection diagram for a hydraulic accumulator with a five-terminal manifold is considered. Installation is carried out according to the diagram, which is in the technical documentation. A manifold with five outputs is screwed to the hydraulic accumulator fitting. The remaining 4 outputs from the manifold are occupied by a pipe from the pump, water supply to the home, a control relay and a pressure gauge. If you do not plan to install a measuring device, then the fifth output is muted.
Connecting the accumulator to the water supply system
After assembling all the components, the pump is first lowered into the well or well (if the system is equipped submersible pump), or a hose (if the pump is surface). The pump is supplied with power. That's all, actually.
Important! All connections are made with the winding of FUM tape or flax. It should be understood that the pressure in the system will be quite high. However, you shouldn’t be too zealous either; everything is good in moderation. Otherwise, there is a risk of the nuts on the fittings breaking.
Having dealt with the installation, you can move on to the issue of replacing the membrane, which more often fails in models with a vertical arrangement. Here we will compose step by step instructions with photo examples.
| Photo example | Action to be performed |
|---|---|
 | First, unscrew the bolts of the flange of the dismantled hydraulic tank. They are wrapped “into the body” or tightened with nuts - depending on the model. |
 | Once the bolts are removed, the flange can be easily removed. Let's put it aside for now - to remove the failed bulb, you need to unscrew another nut. |
 | Unfold the container. At the rear there is an inflator nipple. The nut also needs to be removed. There can be two of them, one of which acts as a locknut. This is done with a key of 12. |
 | Now, with a little effort, the pear is pulled out through big hole, from the flange side. |
 | We lay out the new pear and expel the air from it. This is necessary to make it more convenient to install it in the tank. |
 | Having folded it in four lengthwise, we insert it completely into the container, including the part that was outside when dismantled. This is done so that it is possible to get the nipple into the hole intended for it. |
 | The next stage is not for people with full physiques. Experienced craftsmen they say that in order to install the nipple for the hydraulic accumulator in place, sometimes you have to call your wife for help - they say, she has a thinner hand. |
 | Once in the hole, you must tighten the nut so that during further assembly it does not go back. In this case, everything will have to start again. |
 | Straightening seat pears and tighten the nuts on the nipple. There's only a small matter left... |
 | ... - install the flange in place and tighten the bolts. When tightening, do not overdo one screw. Having tightened everything a little, we begin broaching according to the system of opposite units. This means with six bolts the order is 1,4,2,5,3,6. This method is used in tire shops when pulling wheels. |
Now it’s worth taking a closer look at the required pressure.
What pressure should be in the accumulator: check the system for operability
Factory settings for hydraulic tanks include set pressure at 1.5 atm. It does not depend on the volume of the tank. In other words, the air pressure in a 50-liter accumulator will be the same as in a 150-liter tank. If the factory settings are not suitable, you can reset the indicators to values convenient for the home technician.
Very important! You should not overestimate the pressure in hydraulic accumulators (24 liters, 50 or 100 – it doesn’t matter). This is fraught with failure of mixers, household appliances, and pumps. 1.5 atm., installed from the factory, were not taken from the ceiling. This parameter was calculated based on numerous tests and experiments.
The cost of various models of hydraulic tanks on the Russian market
You can buy a hydraulic accumulator for water supply systems in large construction hypermarkets, specialized stores or on online resources. When choosing a tank, it is better to immediately purchase a volume with a reserve. Of course, you can later buy another one and connect it in parallel with the first one (this is allowed), but the price of a hydraulic accumulator for water supply systems of 100 liters will be lower than the cost of two containers of 50 each. Let's consider some models of such devices with their technical characteristics and prices, as of January 2018.
| Make, model | Pressure (max), atm. | Water temperature (max), ˚С | Tank volume, l | Cost, rub. |
|---|---|---|---|---|
| 10 | 100 | 24 | 1800 | |
| 10 | 70 | 100 | 11800 | |
| 10 | 100 | 80 | 6000 | |
| 10 | 99 | 20 | 1300 | |
| 8 | 50 | 100 | 6000 | |
| STOUT | 10 | 100 | 80 | 4500 |
If we take average values, then the price of a hydraulic accumulator for water supply systems of 50 liters (the most common) is not so high. This means that purchasing this necessary device will not break a big hole in the family budget.
Conclusion
The installation of hydraulic accumulators in the water supply systems of a private home is necessary. This will save you a lot of problems and unnecessary costs. Having once paid a small amount for a hydraulic tank, you don’t have to worry about the performance of your dishwasher or washing machine, or the durability of the pump and faucets.
And finally, we suggest watching an educational video on installing such tanks:
A stable water supply system in the house is the goal of any responsible owner. Homeowners know how difficult it is to avoid pressure surges and fluid supply interruptions in the water supply. A hydraulic accumulator for water supply systems, also known as a pressure, expansion or storage tank, can solve the problem. What types are there, how does a hydraulic accumulator work, and why are hydraulic water tanks needed?
Why do you need a hydraulic accumulator?
Hydraulic tanks for water supply systems maintain a given pressure, create a certain supply of water in the autonomous network and, ensuring a constant and even flow of liquid, eliminate the risk of breakdown of household appliances. This equipment effectively smoothes out pressure surges when consumers use water and when the pumping station is turned on and off.
Why do you need a hydraulic accumulator in a water supply system:
- Maintaining constant pressure in the water supply system and protecting the water supply network from pressure changes. Pressure changes in the system when using several water intake points simultaneously also cause temperature changes. Due to temperature fluctuations, you can get burned while washing dishes, or get caught in a cold shower. A tank with a hydraulic accumulator solves this problem.
- Protection of the pipe piping system from water hammer, and therefore from cracks and ruptures in the pipeline, and, as a consequence, from flooding.
- Extending the service life of the pumping station. IN pressure tank There is always a certain amount of liquid remaining, which first flows to the water intake point when the tap is opened. In this case, the pump does not turn on until the water from the accumulator is used up.
- Emergency provision of a small amount of water (100-200 liters) to consumers when the water supply or electricity is cut off.
Thus, installing a hydraulic accumulator for closed-type water supply systems is of great importance to ensure the stable functioning of the water supply system in a private home.
How is a hydraulic accumulator constructed?
Hydraulic accumulators for water supply are made in the form of a metal container, inside of which a pear-shaped rubber membrane is installed, dividing the container into a pair of parts. The space on one side of the membrane (from the housing) is filled with inert gas or compressed air, and on the other - with water. The rubber membrane is fixed to the vessel body using flanges with a pipe.
At the same time, the hydraulic tank maintains the pressure in the hydraulic accumulator and the entire water supply system at a level of 1.5–3 bar. You can pump air into the vessel yourself using a car or bicycle pump.
In addition, the design of the hydraulic tank includes a hole for supplying liquid and a pressure gauge indicating the air pressure inside the tank. A spool valve is also installed in the tank body, which regulates the supply and release of air, and a filter to remove small debris when pumping liquid from the well.
Water is pumped into the container and supplied to the system using a pumping station, due to which the gas pressure in the hydraulic accumulator with automatic control (ACS) increases. At the moment when the air pressure reaches the limit value, the ACS turns off pumping equipment, stopping the supply of water from a well or central water supply.
The device with the tank is equipped with an automatic control system, the operation of which increases the service life of the hydraulic accumulator. Gradually, the liquid from the vessel is consumed, the pressure drops to a minimum limit, the ACS starts the pump and water is pumped into the container until the required pressure is reached again, after which the pumping station is turned off.
What types of hydraulic tanks are there?
Before choosing a hydraulic accumulator, based on the parameters of a specific water supply system, it is necessary to study the types of the device in question in order to make the right choice.
According to their purpose, hydraulic tanks are divided into three types:
- For cold water. This is a blue or transparent vessel designed for use in cold water supply systems. Working pressure threshold – 8 bar. The hydraulic tank accumulates and supplies liquid to water intake points. For such hydraulic accumulators, the membrane is made of food-grade rubber, which is absolutely harmless to humans.
- For hot water. The container is red, or can also be numbered. This hydraulic accumulator for water supply systems is designed to work with high temperatures liquids. The membrane is made of durable rubber, but the working pressure of the red tank is lower than that of the blue vessels, so they should not be used in a cold water supply system.
- For water heating. These are expansion tanks designed for comfortable and stable operation of a closed heating system in a private home.
Based on the mounting method, a distinction is made between horizontal and vertical water storage batteries. This is important to know when bleeding out excess air, which accumulates in a container of water over time. If you do not do this periodically with your own hands, the system will become filled with air pockets, which can seriously damage it.
So, a vertical tank accumulates air in the upper part, and a special nipple is used to remove it from the tank. It’s easy to clean a vertical hydraulic accumulator from excess gas with your own hands; with horizontal models, everything is much more complicated. To bleed off excess air, you will also need a sewer drain and a ball valve.
Hydraulic tanks with a small volume, up to 100 liters, also have a different method of bleeding air. You don’t need any special equipment for this, just a few simple manipulations:
- Disconnect the equipment from power supply.
- Open the mixer tap and drain the water.
- Wait until the vessel is empty.
- Close the tap.
- Plug the tank into a power outlet to refill it.
Excess air will come out along with the liquid.
In any hydraulic accumulator it is necessary to bleed off excess air at least once a month.
The operating principle of such equipment is approximately the same, let’s look at it in more detail.
How does a hydraulic tank work?
The principle of operation of the hydraulic accumulator is very simple. When the pump is turned on, the membrane is filled with water, its volume increases, as a result of which the air outside the membrane is compressed under pressure. When the pressure in the tank reaches a predetermined value, the pumping equipment is turned off. The compressed gas puts pressure on the liquid and pushes it through the pipeline to the water intake points.
When water leaves the membrane, the pressure in the accumulator decreases. When the pressure reaches a minimum value, the relay automatically starts the electric pump, which fills the vessel again.
The smaller the volume of the storage tank, the more often the pumping station starts. The most common option for a household hydraulic tank is a volume of 100 liters. In this case, the pump turns on on average 7-12 times per hour at active use water by the consumer. With this operating mode, equipment wear is minimal. More frequent relay activations lead to early wear of the membrane and other parts.
As a rule, water enters the storage battery from a well built according to the borehole type. Open well contributes to the fact that the water is saturated with oxygen, which also enters the system. Oxygen also needs to be vented.
Frequent use of hydraulic equipment leads to wear of parts, which can cause a drop in operating pressure in the system. Therefore, it is recommended to completely drain the water once a year and check the pressure in the tank without water.
What to consider when choosing equipment?
The stable functioning of the water supply system depends, first of all, on the right choice hydraulic accumulator. Which tank to choose—blue or red, horizontal or vertical—depends on the intended use of the storage tank.
So, if you plan to maintain normal operation of the hot water supply, then you need a red vessel, for cold - blue, for heating - an expansion tank.
The volume of the hydraulic device also depends on what tasks you want to solve:
- If you are simply going to maintain a certain pressure in the system using hydraulics, then you can get by with a 30-liter capacity. Provided that no more than three water supply points are connected, otherwise a larger tank or another vessel of the same volume is needed.
- To compensate for the lack of water during the period of peak consumption, you will need a tank of 50 liters.
- If you want to remove excessive loads on the electric pump, then you need a hydraulic accumulator with a volume of at least 80 liters.
- To use a hydraulic device as a backup water source, a 100 liter capacity is required.
As already noted, a volume of 100 liters is best option for a hydraulic accumulator for domestic use.
To more accurately calculate the required volume, use the following formula:
Vt = K * A max * ((Pmax+1) * (Pmin +1)) / (Pmax- Pmin) * (Pair . + 1), Where:
Amax – maximum flow rate of liters of water per minute; K – coefficient, which depends on the power of the pump motor; Pmax – pressure when the pump is turned off, bar; Pmin – pressure when the pump is turned on, bar; Pair – air pressure in the hydraulic accumulator, bar.
What pressure should be in the accumulator when there is no water in it? This parameter is indicated on the product body. To lift liquid through a water pipeline 10 m high, a pressure of 1 bar is required, when supplied to a height of 5 m - 0.5 bar. Moreover, if the hydraulic equipment is placed in the basement, then you need to add another 1 bar so that the water can easily rise to the first floor.
Keep in mind that the pressure of the hydraulic tank should be 0.5 bar less than the pressure of the electric pump in use.
How to properly connect a hydraulic accumulator to the system?
Connecting and setting up any hydraulic accumulator to the water supply system with your own hands does not require any special skills, regardless of whether you have chosen a vertical or horizontal option. Connect to the pump, electricity and water supply network as follows:
- Measure the pressure inside the tank (or look at the markings on the body). Its value should be slightly less than the operating pressure of the pump relay.
- Buy a fitting with five outputs to connect the relay, accumulator, pressure gauge, pump and water pipe into one circuit.
- Prepare a relay for pressure correction, as well as FUM tape or tow with sealant for threaded connections.
- Connect the fitting to the vessel using a flange with bypass valve or using a rigid hose.
- Connect all parts of the system one by one. The last thing to screw on is the pipe leading to the pump.
- After connecting all the elements, it is necessary to check the system for leaks. When they appear, it is necessary to seal the joints of the parts with sealant or FUM tape.
- Adjusting the pressure switch for the hydraulic accumulator.
Moreover, if hydraulic equipment is to be used in a water supply system with a submersible pump, then it must be installed in a well or well, but then there is a possibility that the water will “roll back” back. To avoid water “rollback”, you should install check valve on the pump in front of the water supply pipe to the top.
How to adjust the water pressure switch? The accumulator pressure switch is adjusted using two nuts on it. After the pump turns off. The pressure gauge will display the current “top” pressure. If it differs from the recommended one, then by twisting the nut you can adjust it.
“Lower” pressure is also measured. Monitor the pressure gauge readings when draining the water. The pressure will gradually decrease, and when it reaches the lower limit, the pump will turn on and the pressure will begin to increase. The pressure gauge readings at the moment the pump starts are the “lower” pressure. If it differs from the recommended one, then adjust it using the nut.
Now you know how to select and connect a hydraulic accumulator for the water supply systems of a private home correctly so that it works smoothly and efficiently.
