Automatic reducer make-up heating system installation. Feeding the heating system: device and purpose
Periodic replenishment of the heating system, which will be discussed in this article, is one of its maintenance operations. In a normally functioning system, the need for recharge occurs infrequently, but it will not work out completely without it. Otherwise, the performance of heating may decrease, up to overheating of the coolant and complete failure. To prevent this from happening, it is necessary to take measures, that is, to properly organize the timely addition of water to the pipeline network.
Why do you need make-up in the heating system?
The volume of water in the system is not a constant value; due to various circumstances, it decreases over time. A holy place is never empty and the space vacated by water can be filled with air, disrupting the normal circulation of the coolant. The result is known: the water in the supply pipe begins to overheat, which leads to an automatic shutdown of the boiler.
Note. In closed systems, a decrease in the volume of the coolant leads to a decrease in pressure to a minimum, after which the consequences described above occur.
In order to replenish the supply of coolant in the pipeline network in time, a water heating make-up system is needed. It will serve not only as a periodic addition of water, but also as a means of filling the heating network of your home after emptying. You may have a natural question: where does the water from the pipes go, especially when there is no contact with the atmosphere? Let's put the answer in the form of a list:
- most of the water evaporates through expansion tank if the system is open. This is the main reason why the volume of the coolant is significantly reduced. In other cases, the decrease is not so noticeable.
- the periodic operation of automatic air vents, oddly enough, also leads to leakage of the coolant. At the highest points where they are installed, the water temperature is the highest, which means that it evaporates more intensively. The air vent valve, while releasing air, simultaneously removes water vapor.
- permanent work in temperature regime, close to the maximum, as is the case with solid fuel boilers, triggers . A closed heating system needs to be recharged to compensate for the amount of coolant slowly leaving through the valve.
- leaks can be the cause.
Note. The coolant can slowly drip through safety valve and you won't even notice it. Drops quickly evaporate, leaving only a small, barely noticeable spot. To control the process visually, it is recommended to connect a tube to the fitting, directed into a bottle or sewer, but with a break in the jet.
Easy ways to recharge
The easiest way to replenish the water supply is to do it manually. To implement it, you need to lay a section of the pipeline connecting the return line of the heating system with a centralized water supply. In this area, you need to install a shut-off valve and a filter device. A simple make-up circuit is shown in the figure:
This scheme is suitable for any simple heating systems for private houses of a small area. The supply pipeline is connected to the return before the pump, since this section has the lowest pressure and temperature of the coolant. But along with simplicity, this method also has a lot of disadvantages:
- the amount of water in the pipes will have to be constantly monitored by the homeowner, looking into the expansion tank of an open one or watching the pressure gauge of a closed heating system;
- the amount of replenishment of the heating system must also be adjusted independently until the water runs through the overflow pipe of the expansion tank.
Advice. To prevent the coolant from accidentally leaving the water pipe when there is no pressure in it, install a spring-loaded check valve in front of the shut-off make-up valve.
The right solution for open systems would be to organize the addition of water not to the return line, but directly to the expansion tank. Then you do not have to constantly get out into the attic or under the ceiling to assess the level of coolant. The solution is implemented by welding 3 additional pipelines to the tank, as shown in the diagram:
It is assumed that one supply pipe is already welded to the tank. The make-up unit shown in the diagram works as follows: a coolant circulates through the supply and return pipes, its level in the tank is checked by opening a tap on the control pipe. It is lowered into the boiler room to the nearest sewer drain. If water flows out after opening the tap, then the level in the tank is normal. At negative result the control valve closes and the make-up valve turns on. Filling occurs until the coolant runs through the overflow. Although here it is also necessary to do everything yourself, but cold water does not flow directly into the boiler.
Important. Often, boilers, especially solid fuel ones, have a cast-iron heat exchanger, which can crack due to temperature changes. Therefore, during feeding, especially according to the first scheme, open the tap no more than a third so that cold water flows slowly.
Organization of automatic feeding
For those who have no time to mess around in the boiler room, automatic feeding of the heating system is suitable. This will result in the purchase of additional fittings, as well as its installation on site. The essence of the method is the same as in the first simple scheme, but instead of a conventional tap, a whole assembly is installed on the supply pipeline, shown in the figure:
Note. The unit is designed to work together with a closed heating system. In the open, it will not be able to function, because there is too little excess pressure.
The main element of the presented scheme is the pressure reducing valve for feeding the heating system. It works like this: while the pressure in the heating network of a private house is above the minimum, the spring is in a compressed state, supported on one side by the coolant. When the pressure drops below the set limit, the spring, whose elastic force becomes larger, straightens and opens the passage for the flow from the water supply.
Upon filling, the pressure in the network increases again and overcomes the force of the spring, closing the damper. In addition to the reducing unit, the make-up regulator contains a strainer and a check valve. A flow cutter is installed in front of it, preventing the ingress of dirty coolant into the line cold water. The filter element is equipped with 2 manometers in order to determine the degree of contamination by the pressure difference. All fittings are installed on the bypass and are equipped with shut-off valves, which makes it possible to service them.
In a situation with frequent water cuts or with autonomous water supply, the pressure at the inlet to the automatic unit must be provided by a pump to feed the system with a membrane accumulator. But it is not advisable to buy and install a pump only to replenish the heating network. It must be mounted and tied in such a way that, in the absence of a centralized water supply, the pump builds up pressure in the entire house network, pumping water from a spare tank or pool.
Conclusion
Make-up automation is the best option, but not for everyone due to the cost of optional equipment and installation. And yes, you still need to keep an eye on it. Many homeowners find such automation impractical and resolve the issue in the simpler ways discussed above.
Correct and efficient circulation of the coolant directly depends on the amount of water in the heating system. So, the valve for feeding the heating system is necessary in any case. This is due to the fact that even if all the necessary norms and rules are observed, there will be even losses of the coolant, for example, through pipe joints, through the Mayevsky tap or through seals near the circulation pump, etc. In essence, this is a small amount of water, but after a while there can be a significant loss in volume.
To prevent an emergency situation due to these losses, it is necessary to install a device for feeding heating pipes. It can also be said that the volume of water decreases when filters are cleaned from various sludge, and when the temperature drops outside, as a result of which the heating mode changes.
Rice. oneInstalling a heating system make-up device
There are some rules that must be observed when installing a make-up valve:
- It is installed in that part of the heating system where the pressure indicator is minimal. For example, before circulation pump.
- If a mechanical make-up valve is installed, then a tap or valve must also be installed. As a rule, these elements should be placed between the heating equipment and the pipe that supplies cold water.
- If the pressure in the heating system is too low for the make-up device, a pump is installed. High pressure can be generated by the circulation pump.
- You also need to install a shut-off valve in the heating system so that water does not enter the feed line.
- This type of valve must be equipped with a pressure gauge.
The most successful place to install a heating system make-up unit is the place where the expansion tank is connected, the so-called "zero" reference point. In this case, the make-up unit functions most accurately. But many experts recommend installing this unit a little further from the boiler, and on the hot water pipe. This is necessary so that the water mixes with the hot coolant and enters the boiler in this form.
Feed node control methods
The make-up valve for the heating system can have 2 types of control:
- mechanical;
- Automatic.
A mechanical make-up device can be installed in small heating systems. Since there, the membranes of the tanks act on the increased pressure. In this case, the decrease in the volume of water in the heating system can be compensated manually, that is, by simply opening the water supply tap.
Rice. 2
But in order to carry out these manipulations on time, you need to have some experience in performing such work. Since you need to constantly monitor the pressure indicators inside the heating system, and the amount of water. If there is more water than needed, then emergencies may well arise. An automatic make-up unit should be installed in large heating systems that have many branchings.
In new models of boilers, an automatic make-up valve is included in the package. Namely, it becomes part of the automation. If you install such a device separately, then the whole circuit depends on electricity.
Automatic make-up device
The automatic make-up valve works according to a very simple system and does not require outside intervention. You just need to pre-configure all the settings. That is, when a certain amount of water is lost, replenishment is needed, and the indicator of the lowest pressure is also programmed.
The process of operation of such a device is that if the volume of the coolant decreases in a given amount, then the valve is activated and the pump automatically starts. And the pump, in turn, must pump the required amount of water. When the system is filled to the norm, the valve automatically stops feeding the heating.
To install this make-up device, you need to mount a pressure gauge on the cold water supply pipe. You can install any other sensor that will control the pressure level in two directions. It should be adjusted to the working pressure parameters. A relay, contactor, etc. is also mounted in this place. It is these elements that turn on the exhaust pump if the amount of water in the heating system has decreased to a certain level. The group in the other direction stops taking water, that is, turns off all active elements.
It can be concluded that a valve with an electric motor controls the pressure level and the volume of the coolant in the heating pipes.
Automatic boiler feed unit
The make-up valve located in the boiler automation is equipped with a pressure reducing valve - this is its main part (Fig. 2). He, in turn, has a membrane in the configuration. This part is in the closed state, thanks to the spring, when normal system pressure. The tension of the spring is directly dependent on the pressure indicators.
Rice. 3 make-up valve for gasboiler
When the water level drops, and, accordingly, the pressure on the valve stops, then the membrane is not supported, and the spring acts on the stem, pushing it down. And a hole is formed in the saddle. Water from the water pipe enters through this hole. When the right amount of water is restored, then, accordingly, the pressure too. The membrane closes under pressure.
The pressure reducing valve in the boiler automation works quite often, namely when the automatic air ducts are triggered. Automation often removes air from the heating system, which means that the make-up valve in the boiler also works often.
Also, a check valve should be installed after the pressure reducing valve. This is necessary so that water from the system does not penetrate into water pipe. Sometimes automation provides for this, but in some models of boilers this is not. Then it must be installed as a separate part.
Most apartments and houses use water or special synthetic products as heat carriers for the heating system. In order for the engineering network to work without interruptions, it is necessary auxiliary elements: relays, sensors, controllers. In addition, to maintain the working pressure in the pipeline, heating will be needed. Consider what role it performs, the main varieties, how it works and whether it can be assembled independently.
Unfortunately the volume working fluid in the heating system is unstable, over time it becomes less and less. With a decrease in pressure, the free space is filled with air, traffic jams appear. The circulation of the liquid stops, which leads to overheating of the equipment. As a result, the boiler may fail, which threatens with significant material costs.
Consider the five main causes of water loss in pipes:
- When the heating circuit is open, hot water starts to evaporate from the expansion tank. In this case, it is easy to notice a decrease in pressure in the pipes, as well as replenish it again.
- From time to time the automatic air bleeder works. This is due to the fact that the valve releases not only air, but also water vapor. Although the losses are not as great as in the first case, over time, the pressure drops to a critical level.
- When the boiler has been operating at maximum efficiency for a long time, a safety valve is activated to avoid overheating. At this point, the coolant may be discharged.
- Small leaks are also one of the reasons for the decrease in pressure in pipes. Often microscopic cracks are hard to see, but the water slowly leaves the system.
- Over time, the inner surface of the pipe becomes corroded and destroyed. Because of this, the total volume of the heating system increases. It is difficult to recognize this cause, but restoring the working fluid pressure is still important.
To avoid such a development of the scenario, heating pipes are replenished. Often, automatic devices are suitable for this role, they work constantly, eliminating the human factor. With the help of make-up, the lost volume of water is replenished and the equipment can work without failures, which saves the owner of the premises.
Make-up is needed to restore the volume or pressure in the heating system. When the device adds working fluid, it automatically stops after equalizing the main indicators. Most often, the equipment is connected to a cold water supply, liquid is taken from there. Another option is a storage tank, where you have to manually replenish the stock, and is usually intended for synthetic products.
Two types of heating make-up have been developed:
- Manual. Designed for small closed loops where small pressure jumps occur. A manometer is used to detect leaks in a timely manner. When the pressure drops, opening the corresponding tap supplies water, thereby compensating for losses. The liquid flows between the pipes either independently or with the help of a special pump. Budget solutions have an overflow pipe in the expansion tank, when the water reaches this mark, the liquid supply is stopped. The only disadvantage of such a device is the need for constant supervision and experience in performing the procedure.
- Automatic. The equipment independently processes data from the pressure gauge. When the critical point is reached, the working fluid supply valve opens. As with manual control, the pressure in the cold water supply is sometimes not enough, so pumps are installed. When water losses in the heating system are restored, the valve closes. The advantage over the manual method is the automation of the process. When leaving home for a few days, there is no need to worry that the boiler will overheat or fail. The disadvantage is the increase in electricity costs.
The need for recharge does not always arise. So that the equipment does not stand idle, it can be used for other purposes. It is able to fill the pipeline with water or synthetic coolant. Useful equipment in the beginning heating season when testing the entire system. And also the device is suitable for flushing pipes, discharging water or filtering it from coarse particles.
Like any equipment, make-up consists of several parts. Let's consider each detail separately.
Actuating mechanism
With manual control, one valve is installed through which water is supplied or shut off. Automatic equipment may contain different kinds remote control devices. The most popular option is a pressure reducing valve. It consists of three parts: a shut-off valve, a non-return valve and a pressure reducer. At the same time, it is installed both in mechanical systems and equipped with electrical control sensors.
The lower pressure threshold is set in the actuator. When the pressure gauge detects losses, the membrane releases the spring, which acts on the working stem, after which the valve opening opens. When the pressure returns to normal, the membrane again presses on the spring and the rod snaps into place, closing the passage with a cone.
You can set the pressure threshold at which the supply of working fluid will begin using a screw fixed at the top of the actuator. Having installed it in a certain position, the position is fixed with a lock nut. In order not to make a mistake with the adjustable pressure, the device has a pressure gauge.
check valve
The operating fluid from the heating system must not be mixed with potable tap water. This will lead to negative consequences:
- They will make the water unfit for human consumption due to the development of bacteria.
- Since heating pipes are gradually destroyed inside, corrosion can enter the water, which is harmful to health.
- Reduced boiler efficiency due to pressure loss and temperature drop.
The coolant can enter the water supply during make-up if the pressure in the heating system is higher than in pipes with cold water. Another reason for mixing is that the valves have failed and started leaking.
To avoid an unpleasant situation, a check valve is placed behind the actuator. Some designs include this part inside the pressure reducing valve. Modern make-up designs have a "flow breaker" installed upstream of the equipment.
Accumulator and pump
When the pressure in the heating system is higher than in the water supply, a pump will be needed to make up for the loss of working fluid. Automatic or manual water supply is not possible. If the check valve fails, then the coolant will be discharged into the cold water supply.
Pumps with a storage tank have been developed, in which there is always a supply of water to make up for losses in heating. This solves the problem even when there is low pressure in the cold water supply. Pumps can be either manual or automatic. The first option involves the installation of a storage tank above the level of the expansion tank. Such a mounting scheme is called gravitational. In the second case, a hydraulic accumulator is used, connected to a membrane that is constantly under pressure.
Vertical pumps are available without a storage tank. They are intended for private houses and are installed in wells under water.
Filters
Sometimes a liquid with impurities is supplied in a cold water supply, which can disrupt the operation of the heating system. For protection in front of the actuator, two types of filters are installed:
- Garbage cleaning. Inside, a mesh with small cells is used, in which polluting particles get stuck. Sometimes such a filter is built into the actuator.
- Chemical cleaning. To avoid corrosion of heating pipes soften the incoming water. Usually, calcium salts are eliminated with the help of reagents.
All types of filters should be cleaned regularly. So they will reliably perform their functions and not clog the valves.
open system has an expansion tank. It is installed in the highest part of the "highway". It helps to cope with the thermal expansion of water, compensating for pressure in heating. To determine the liquid level, a control tube is brought out of the tank into the kitchen or into the bathroom. A stop valve is installed at the end of this tube, it will help to avoid leakage of excess water.
During the control time, the valve opens. If the water is flowing, then everything is ok. Otherwise, the water level must be replenished immediately.
The gravity heating system has three main elements:
- a ball valve is necessary to transfer the coolant from the water supply to heating;
- the filter helps to eliminate dangerous impurities;
- non-return valve prevents mixing drinking water and fluids from the heating system.
Closed systems are characterized by internal high pressure, so manually adjusting the coolant level is difficult. To solve the problem, automatic equipment is installed. It independently monitors losses and replenishes them as needed. It is important that such a device has filters built into the gearbox, a check valve and a gate valve. Closed circuits should always be equipped with a pressure gauge to visually monitor the pressure inside.
Selecting an installation location
It is not allowed to embed structures. make-up anywhere in the heating circuit. The norms of the installation site are described in SNiP, here are some of them:
- Make-up equipment is installed in a place with a minimum pressure in the heating system. In a closed circuit, the installation is mounted near the pumping unit.
- To ensure that the coolant does not get into the cold water supply, additional shut-off valves are inserted.
- If the circulation pump starts to increase the pressure in the heating system in excess of what the make-up gives, you will need additional pump in front of equipment that compensates for losses in the circuit.
When choosing a make-up heating system, be guided by its reliability and ease of use. If you have a small house or apartment, then a simple design is enough. It is recommended to choose an actuator with a minimum adhesion coefficient. Such material is resistant to the formation of limescale, which means it will last longer.
Clear Cartridge stop valves you can run the following instruction:
- Isolate make-up equipment.
- Unscrew the control knob at the bottom of the valve.
- Remove the cover by unscrewing the adjusting screw.
- Use pliers to replace the cartridge.
- Collect the device back.
Having installed recharge, carry out timely repairs of its parts and then the house will always be warm.
The coolant in most modern heating systems water or special synthetic fluids protrude. There are no significant differences between the two options. Each of them involves heating the line without disintegrating into constituent components, and each requires replenishment of the heating system (due to inevitable losses).
Technical parameters of working fluids
The working fluid is not ordinary water taken from a water supply system or the nearest reservoir. On the contrary, this water must undergo special treatment, useful substances must be added to it, and impurities that adversely affect the pipeline and other elements of the system must be removed. In most cases, such a liquid is poured into centralized heating networks. Properly treating water is not so difficult, and it is inexpensive, and the make-up process itself can be performed in boiler rooms.
Note! The main disadvantage of water as a coolant is that it freezes when it reaches 0C, while heating appliances and the pipeline after that is often destroyed.
As for synthetic compounds, their freezing temperature is noticeably lower, and their chemical composition already optimal for heating mains. But due to the high cost, such liquids are mainly used in individual systems closed heating.
What is this drink for?
You may have come across the term “recharge valve” before. What is it and why is it required? Let's try to find out. Let's start with the fact that in all closed heating systems (regardless of the type of circulation of the working fluid used), the coolant moves from the boiler, passes through all the heating devices and, ultimately, returns back. And in order for the circulation to constantly occur efficiently enough, it is necessary to constantly maintain the working pressure, which, in turn, is directly related to the volumes of hot liquid.
Even if during the arrangement of the system all the requirements and standards were met, as well as with its absolute tightness, the volume of the coolant will still decrease over time and, alas, this cannot be avoided. The reason for this is extremely simple: there will be leaks in the network anyway. Liquid can leak out through the connections of individual elements of the system, through the stuffing box seals of the circulation device, and a small amount of liquid is lost with each opening. Of course, in a closed system, these losses are insignificant, but sooner or later all this adds up and can cause unexpected problems. The situation is only aggravated if any system failure occurs.
The conclusion is obvious: the volume of the heated coolant must be periodically replenished. For this purpose, the make-up valves mentioned above were created.
Where to install?
The make-up valve, as well as other technological components of the system, should be installed only in a place strictly designated for it. Consider the basic requirements that are put forward for the installation of this device.
Earlier we talked about what norms and recommendations of SNiP should be followed when installing heating systems, in addition to this article, we advise you to read this information
- All feeding valves are mandatory equipped with pressure gauges!
- The replenishment of the heating system, more precisely, the valve itself, must be equipped in the place of the network where the pressure of the working fluid is minimal. Speaking of systems closed type, then in them such a place is precisely the entrance next to the pumping equipment.
- In order to prevent water from the network from entering the make-up line, it is also recommended to install an additional shut-off valve.
- If a valve with mechanical type control is installed, then the installation of a reinforcing valve or a valve is mandatory. They need to be mounted between the cold water supply line and the heating circuit itself.
- If the circulation pump achieves a pressure higher than the pressure created by the make-up valve, it is also mandatory to install a booster pump.
For a more detailed acquaintance with the process, we recommend watching the thematic video.
Video - Feeding the heating system
Make-up types: mechanics and automation
There are two ways to control the feeder:
- mechanical;
- auto.
Control method No. 1 suitable where small heating systems are used. In this kind of lines, all pressure drops of the working fluid are regulated by means of special membrane tanks. At the same time, it is much easier to restore the loss of coolant by manually opening a tap on the pipeline supplying cold water. This method is extremely simple, but is associated with certain inconveniences: to perform such seemingly simple manipulations, experience is required, in addition, appropriate technical skills and knowledge are needed.
Note! If there is a use of a mechanical valve, you yourself will have to deal with the control of intra-system pressure in a closed-type network. And if the volume of the working fluid increases too much, then this is fraught with emergency situations.
But the replenishment of the heating system through automation is used in large highways with significant branches. Sometimes they are bundled heating boilers, which also become elements of their systems. Installation of such valves does not cause any difficulties, since it is quite possible to handle it with your own hands. Although there is one “but”: after installing an automatic valve, the entire heating network will become volatile. And you should definitely pay attention to this when choosing one or another type of feed unit.
You can get more detailed information about the technical parameters of the valves, as well as their average market value, from the table below.
Table. Comparative characteristics of popular make-up valves
Name | Material | Type of | Diameter cm | Limit temperature | Adjustment range | Price |
Honeywell VF04 1/2 E | Brass | Mechanics | 1,5 | 70 degrees | Up to 6 bar | 2600 rubles |
ISMA 1/2 | Brass | Mechanics | 1,5 | 90 degrees | up to 4 bar | 1350 rubles |
Meibes Fuelly 1/2 | Brass | Automation | 1,5 | – | 0.43 bar | 1710 rubles |
Time 1 | Brass + plastic | Automation | 3 | – | Up to 1.5 bar | 3680 rubles |
Caleffi 1/2 | Brass + plastic | Automation | 1,5 | 65 degrees | up to 4 bar | 3520 rubles |
Watts Alimat Alomd 1/2 | Brass + plastic | Automation | 1,5 | – | up to 4 bar | 3750 rubles |
The principle of operation of the automatic filling valve
The principle of operation, as well as the installation process, for such a device is extremely simple. All operating parameters must be configured in advance. Pre-program future water losses - as a rule, you should also specify the minimum pressure in the network. And if the volume of the working fluid decreases, for example, by 10 percent, then this will activate the valve, which, in turn, will start the pump.
With the help of this pump, cold water from the supply pipeline is pumped into the heating main in the required volumes. And as soon as the fluid losses are replenished, the valve will work again and stop the automatic supply of coolant.
It is quite possible to cope with the installation of the described device alone. First, on the pipeline supplying cold water, you need to install a pressure gauge or any other contact-type electronic sensor (with the help of such a sensor, the user will be able to adjust the pressure simultaneously in two directions). One of the groups must be set to the minimum pressure in the network.
It is in this place that a contactor or an intermediate relay should be mounted. And as soon as the volume of hot coolant in the closed line decreases, this contactor initiates the activation of the mechanism that will start the extraction pumping equipment. There is a second group - it is necessary in order to deactivate all these processes when the fluid losses are replenished. The actuating element in this case can be an electric valve - a kind of valve equipped with an electric motor.
Important note! If the heating system is recharged by means of automation, then it (automatic) will independently both control the working pressure and calculate the compensation volume of the liquid.
Bypass make-up - when might it be needed?
It just so happened that almost all closed-type heating systems are able to function normally only at high pressure of the working fluid. Although this is not the only important factor, since the temperature of the coolant also takes place.
So, if the temperature rises, then this leads to thermal expansion of individual technical nodes networks. And in order to compensate for this expansion, a special hydraulic accumulator (also known as an expamzomat) is installed, which is able to absorb excess hydraulic energy or, conversely, give it away in case of a shortage. The accumulator is connected in the same way as a plumbing bypass.
Make-up of open type systems: diagrams, instructions
A distinctive feature of an open heating main is that there is no high pressure in it. In this regard, an expansion tank, albeit somewhat modernized, can serve as a kind of sensor for reducing the volume of liquid. This tank should be installed at the highest point of the system.
Note! Make-up in this case will be carried out exclusively with a decrease in the volume of coolant in the tank. To find out if the level has really dropped, you need to open the control pipe: if there is a shortage of coolant, there will be no pressure.
Often the outlet of this pipe is arranged in the kitchen or in the bathroom. And if there is no pressure during the revision, then it is necessary to add working fluid to the system. For this, another element of the feeding system is used - a node that connects the heating network to the water supply. From a constructive point of view, this node will include such elements.
- Ball valve that closes / opens the flow of water to the network.
- Non-return valve - it is needed in order to prevent the return of liquid from the network to the water supply. This can happen, for example, if there is no water in the centralized water supply pipeline.
- Filter. As you know, the quality of tap water does not always meet the requirements, so it needs to be further cleaned of various kinds of debris. If this is not done, then a layer of scale will form on the inner surfaces of the metal elements.
It is according to this scheme that the heating system is fed. open type. But it is worth remembering that you need to install an air vent in advance, with which excess air will be removed. We also add that for competent replenishment of the volume of water, its minimum temperature indicator is needed.
Note! A simpler make-up scheme may consist of an ordinary storage tank, although the water level in this case must be monitored visually.
Feeding a closed-type network: diagrams, instructions
If the line is closed, then the pressure in it, as noted above, is increased, therefore, the previous scheme will not work in this case. Here it is necessary to install exclusively an automatic make-up valve. The principle of operation of such a valve is described above, but we will consider a simple circuit its installation, which you can do yourself. It consists of several elements (in the following order): tap -> pressure gauge -> feed reducer.
By the way, it is the gearbox that is the main element of this system. It consists of several elements below.
The device and features of a closed heating system
Earlier we talked about how a closed heating system works, in addition to this article, we advise you to read this information.
- Stopper platform restricting the flow of fluid from the feed pipe.
- Adjustment unit, which includes a membrane and a special rod with a spring. The block itself is located on top of the device.
- Check valve - we have already considered its function.
Video - Make-up reducer
First, the minimum pressure in the network is set using the adjustment unit. During this time, the working fluid will contact the diaphragm, preventing the stem from dropping. And after the pressure drops below a predetermined mark, the spring will press on the rod and it will still fall. As a result, the damper will be opened, and water from the pipeline will begin to flow into the heating network. And when the pressure returns to normal, the rod will return to its original position, stopping the supply of coolant.
The reducer should be installed on the "return" pipe directly at the entrance to the boiler, since it is here that the pressure is minimal. If the system is equipped with a circulation pump, then the feeding unit should be marked already in front of it, otherwise, when it (the pump) is operating, the pressure may “jump”, which, in turn, leads to false activation of the gearbox.
Note! The volume of passage ranges from 6 to 12 liters per minute, a more specific figure depends on the set value.
As a conclusion
Feeding the heating system helps to avoid utility emergencies. Moreover, with its help, the required pressure of the working fluid in the system is maintained. As for the feed valves specifically, automatic devices allow you to control these processes remotely.
Each heating system requires technical components that can make its operation safe. One of these elements is the valve responsible for automatic feeding. What is this valve? What are the features of its installation? What are its operational benefits? The answers to all these questions can be found in this material.
What is it for?
The closed heating circuit provides for the circulation of the coolant in the direction from the boiler installation through all heating devices. After that, the coolant makes a reverse movement. For maximum efficiency of the process, the pressure inside the system must be kept at the required level. The fulfillment of this task is directly dependent on the availability of hot water.
It is impossible to save the initial amount of coolant in the system. A properly assembled heating system, with ensured tightness and compliance with all norms and rules, can somewhat reduce the loss. But it won't get rid of her. Even the most drastic measures will not be able to save from leaks.
Yes, such losses are insignificant. But over time, all the small losses are added, and a solid result is obtained. System failures greatly complicate the situation. So that hot water circulating in the system must be constantly topped up. This is the function of the feed valves.
Where to install?
Such a valve is a technical element. Therefore, it must be placed in a strictly defined place. When performing installation, you must adhere to several rules:
The make-up valve must be installed in places of minimum operating pressure produced by the coolant. If you need to install in closed system, then such places are the inlets in front of the pump equipment.
With mechanical control of the valve, it will be necessary to install a crane or valve valve.
Forcing the working pressure in excess of the latter formed by the make-up valve means the need to install a booster pump.
Water must not enter the make-up line. To prevent this, a reclusive clan is needed.
- a mandatory element of each valve for make-up.
Mechanic or automatic?
Not all make-up valves are the same. They differ in the control system. So, there are valves with mechanical and automatic control. Mechanical valves are suitable for small heating systems. In such a system, it is easy to compensate for water losses. One has only to open the tap for cold water supply. But there is one condition here.
To install such a valve, you need to have experience that will allow you to perform the described operations. In addition, you need to have technical knowledge and certain skills. But there is one more thing, but. This method requires constant personal supervision of the pressure in the system. If it increases greatly, then an emergency situation may arise.
Large and branched systems are not suitable for mechanics. This requires the installation of an automatic valve. Often such systems are part of the heating boiler, and therefore become part of its automatic systems. Installing an automatic valve is not difficult. But here, too, there are nuances. Like any automation, it is very energy dependent. And this makes the entire heating system dependent. This must be kept in mind when equipping such systems with automation.
How an automatic valve works
This device works very simply. The operation parameters are configured in advance. Water loss indicators are preliminarily entered into the program. This happens by laying the indicators of the lowest pressure level. When the data decreases, the valve starts to work pumping station. She, in turn, pumps cold water into the system until the required volume of liquid is completely restored.
When installing the device, first, a pressure gauge is installed on the line that supplies cold water. This makes it possible to control the pressure in both directions. The adjustment of one of its groups takes place focusing on low pressure. An intermediate relay or contactor is installed there. It, in case of a decrease in the volume of the coolant, turns on the extraction pump.
After replenishing the volumes of water, group number two brings all links into a passive state. For the actuator, you can use a valve with an electric motor.
Bypass make-up circuit
Heating can operate effectively only with a high operating pressure of the coolant. But the main factor in this matter is the heating stage of the working water.
If the temperature of the coolant increases, but along with it, the expansion of the system nodes also occurs. In this case, some compensation for such an increase is necessary in order to avoid an emergency situation. A hydraulic accumulator expander can help with this. It is able to carry out the accumulation of hydraulic energy in case of its excess and return, in case of its deficiency. You need to connect such a unit with a bypass circuit.
Thus, make-up makes it possible to prevent the occurrence of emergencies. In addition, it maintains the volume of coolant necessary to maintain the correct functioning of the heating system.