Buderus gas boiler drops water pressure

Why does the pressure in the gas boiler drop or grow: the causes of the pressure of the pressure method of preventing problems

Work to ensure the proper functioning of heating equipment does not end on its installation. Service requires a certain level of knowledge from the owner and constant monitoring the state of the system. It is important to understand why the pressure in the gas boiler drops or grows, which is why the equipment functions with changes.

The article presented by us describes in detail all the reasons for the instability of pressure in the system of preparation of the coolant and hot water. We will talk about how to eliminate problems and maintain indicators in the normal range. Our recommendations will help to cope with planning breakdowns and prevent failures in work.

What should be the pressure in the heating system

Heating systems can be divided into two types. closed and open. In the open, the pressure adjustment function is performed by a non.cell expansion tank.

The capacity is installed at the top point of the heating circuit and serves to keep the expanding when heating the coolant, for air removal, and also acts as a safety valve. The working pressure in such a system depends mainly on the temperature of the heating water.

Most often, when organizing heating in houses and apartments, closed heating systems are used. They are more effective, safe, but require constant control of pressure.

It is very important to monitor the pressure, temperature of the coolant, respond to any signs that are not characteristic of the normal operation of the heating system. a knock, frequent discharge of hot water through the safety valve, cold sections of the contour

The pressure in the closed type circuit occurs due to forced circulation carried out using the pump. Deviations of pressure from the norm can lead to equipment failure.

The nominal pressure in gas boilers of various models can vary, it is determined by the technical characteristics of the equipment

Designing the heating system, the pressure is calculated taking into account the height of the water column, the length of the system, the characteristics of the connected equipment, the cross.section of the pipes.

To adjust the working pressure, you need to focus on the following parameters:

  • Technical characteristics of a gas boiler. The manufacturer indicates the capabilities of the equipment and the settings settings in the instructions.
  • The temperature of the coolant. The larger the temperature, the greater the pressure in the circuit, when it decreases, it decreases. Therefore, the adjustment and measurement of pressure in the gas boiler and the heating circuit must be carried out before and after heating the coolant.
  • Circuit and expansion tank volume. The size of the accumulator has a direct effect on the pressure in the heating circuit, on the range of its fluctuations.
  • Permissible pressure indicators for the least “weak” element “of the system. The pressure in the system should not exceed the permissible values ​​for each of its elements. For example, polypropylene pipes, which are on average for a pressure of 25 bar at room temperature, at a temperature of 90 ° C withstand an increase in pressure only up to 7–9 bar.

The minimum pressure in the circuit can be 0.5-0.8 bar, the exact regulatory values ​​are indicated in the instructions, in accordance with them, the pressure sensor is set up for the required value. When pressure falls in the heating system below 0.5 bar, an emergency situation occurs in which a stop or damage to a gas boiler is possible.

The highest pressure value in the system is up to 3, less often up to 4 bar. For a five.story building, pressure values ​​up to 5 bar are tuned, for ten.storey to 7 bar. When settings, it is necessary to adhere to the difference in the pressure between the outgoing and return pipe. it should be 0.3-0.5 bar. After starting the heating, check if this.

Buderus gas boiler drops water pressure

Natalia, the coolant is flowing down, but there are no flows. Maybe a hole in the coil of the combustion chamber. He just boils and evaporates into the pipe?

Natalia, good afternoon!You have not indicated the brand of the used antifreeze. The pressure in the expansion tank should be within bar per dry. T.e. Checking and pumping the tank is carried out with a drained coolant. If the pressure reduced in the air cavity occurs. It is necessary to check the expansion tank, there should be no air leaks either by nipple or the seam of the expansion tank. If the tank is working, it is necessary to look for a heat carrier leak in the heating system. The boiler is disconnected from the heating system (the taps are overlapped) and excessive pressure in the heating system is pumped up, and pressure is controlled.

Good afternoon! The heat carrier is thermagent. They did not notice through the nipple of air leaks. After the gazmiers leaked the coolant from the expansion but the tank (6 liters), pumped the pressure in the. Tank 1.1, raised the pressure of water in the boiler to 1.6, after 4 days the pressure in the boiler to 0.4 again fell (the boiler worked), again called the gas workers. At first they measured the pressure in the expansion tank-0.7 (not on dry), then pumped pressure to 0.9-1 in it, then water was picked up in the boiler to 1 water.5 and left, advising to put another expansion tank. To my question “why?”, they said that it will not be worse. After 4 days, the pressure in the boiler is again 0.6., over, on the first day, it immediately fell to1.2, then slowly to 0.6. Tell me what will happen in the boiler if the pressure in the expansion tank is pumped up to 1-1.1 (for dry)? And whether the second extensor tank should be put?

Anton, the boiler works less than 5 months. Could a hole really appear in the coil during this time? And if so, how to check it?

Natalia, I don’t say anything about the hole. Maybe it was with Novya?! Verify. simply. Turn off the system, fill with water. And how everything cools to watch. Does the combustion from the boiler leak

Why pressure drops

In addition, to provoke a decrease in pressure in the gas product is capable of improper installation. It is important to consider that the values ​​in the pipes are affected by their height and length, the effect of water on other parts, the device of the main routes. If the pressure begins to decrease more and more often, it is necessary to find out the reason as quickly as possible and try to decide how to raise pressure on the Baxi boiler.

How to increase pressure in the Baxi gas boiler and the causes of its fall

Before raising the pressure in the Baxi boiler, it is necessary to determine what provoked this problem. After detecting a negative factor, it is worth taking on its elimination. the faster this is, the more chances to avoid serious breakdowns in equipment. Depending on the established cause, simple actions are performed.


If leaks have become a negative factor, it is necessary to find and seal them using special substances. To accurately detect dangerous places, it is recommended to check all the joints with a napkin. with it it is easier to see where the water flows. It is worth carefully examining all the joints.

If necessary, it is allowed to use the compressor. To do this, before raising the pressure in the Baxi gas boiler, all the liquid is drained from the system, and then, using the device, the test is checked. Where an extraneous sound is heard, there are leaks. If radiators are built into the walls, it is better to invite specialists.

The boiler is incorrectly selected

This does not happen so rarely. Consumers are mistaken in the calculations and acquire unsuitable equipment, the power of which does not correspond to the specified values ​​of the pipeline. The drop in pressure in this case will be constantly. A similar problem can be solved if you set up the Baxi boiler so that the pressure does not fall. In some situations, the installation of additional equipment will require or eliminate several radiators. One of the options for high.quality equipment Boiler wall walls Eco Four 1.14 f, baxi

Expansion tank

  • Open a fitting on an expansion tank, remember the testimony obtained.
  • Add air until all moisture leaves.
  • The action is repeated again until the parameter reaches 1.3 bar.
  • After that, the tank is filled again.

Damage of the heat exchanger

The appearance of cracks on parts is easy to find on greenish spots on the surface. It is required to carefully clean the place of the malfunction, after which, using a burner or soldering iron, we seal. However, such a repair is short.lived, after some time it will be necessary to completely replace the part with a new.

Three.way valve

The violation of the three.way valve negatively affects the functionality of the entire boiler. It is recommended to carefully check its condition. As a rule, a lot of debris and dust accumulates at the place of its location, so it is necessary to carefully clean the element before pumping up the pressure in the Baxi boiler.

The presence of air in the system

  • Measure pressure.
  • Disconnect the unit.
  • Put a container under the valve on the radiator, open it.
  • Air will begin to come out (accompanied by hissing), a small amount of water can be poured out. Wait until the air stops going out.
  • Turn on water, serve it and simultaneously monitor the testimony on the pressure gauge. After the values ​​are achieved, the taps need to be closed.
  • Turn on the boiler, follow its work. In the presence of extraneous sounds, the process is repeated.

Gas problems

The deficiency of fuel can also cause pressure reduction in the unit. Closure of the highway, malfunctions of the fuel supply valve, as well as gas leaks can provoke the problem.

Safety valve

The reset valve is present in the security system or mounted autonomously. It is required in order to shade excess pressure during the operation of the unit. The spring exerts pressure on the shutter, the movement of water is blocked. With an increase in pressure, it is compressed, after which excess air or liquid comes out. In such details, the spring wears out quickly enough, it is enough for about 7-10 cycles. As a result, the pressure is unable to remain constant and is regularly reduced. In this case, before the Baxi boiler should be set so that the pressure should not be carried out, the parts should be completely changed.

Measuring devices

Manometers also periodically fail or begin to indicate incorrect indications. In this case, it is initially required to compare the readings from several devices. After that, it is recommended to either replace the device with a new one, or just fix another sensor on the boiler feed area. The video discusses the reasons for the drop in pressure in the gas boiler

Sometimes there are blockages in a pipe connecting the heating system and a pressure gauge. It is recommended to clean it, perhaps this will be enough for the pressure parameters to increase. Otherwise, you will have to replace the part with a new. To exclude pressure reduction in the Baxi gas boiler, it is recommended to carefully monitor all indicators. Correct installation and use, regular prevention will help extend the operation of the device. If the pressure during operation periodically drops, but it does not work to understand the reasons on your own, it is best to contact an experienced specialist.

Why does the pressure fall in the gas boiler

There may be several reasons for the pressure in systems with compulsory circulation of the coolant:

  • Loss of fluid due to violation of sealing the circuit or service devices.
  • The heat exchanger due to the long operational period and the rigid, not passed the filtration process, water was covered with a growth of salt layering (scale).
  • Long work at high temperatures leads to the formation of air in the system. As a result, traffic jams appear that prevent normal fluid circulation, which leads to a decrease in the general pressure of the system.
  • The integrity of the heat exchanger was violated.
  • The primary sensor failed.

The main part of the breakdowns can be eliminated independently. And in order to understand how to raise pressure in a gas boiler, you need to correctly determine the reason so as not to encounter problems of a different nature.

The video show how to increase the pressure in the boiler

Leak due to impaired sealing

The loss of the coolant is the most common cause of lowering pressure in the boiler and heating system. To find a problematic place, a superficial inspection of the entire contour is carried out. Places with impaired sealing, as a rule, are visible to the naked eye. water drips out of the connection site. There are also cases when a leak is observed on a whole section of the pipe, but in this case you will need a complete replacement of the site or partial with the installation of a passage coupling.

Interesting! It is easier and cheaper to repair a plastic pipeline. It is enough to cut a small damaged area and connect the parts with a coupling.

The elimination of leaks in places of connection of a metal.plastic pipeline has its own nuances. For example, after the promotion of the threaded part, a complete replacement of the FUM tone will be required.

The situation is more complicated if the cause of the leak became a faulty air vent, a drainage valve or a cracked heat exchanger. Perhaps in this situation you will need a complete replacement of details.

If leaks occur in a warm floor system, which is located under a layer of concrete and other finishing material, or on a pipeline walled up in the wall, the process of detecting defective places is almost impossible without removing decorating casing.

The way out of this situation may be the use of thermal imager. It will help to accurately determine the place where the coolant follows.

Opening a crane with hot water

This problem often occurs when using a double-circuit boiler due to its structure. After the opening of the hot water crane is opened, the boiler almost completely switches to the maintenance of the hot water, only partially maintaining heat in the heating circuit.

As a result, the remaining coolant loses heat, and the pressure drops. But this is observed only with prolonged operation, for example, during a bathroom set or a shower adoption. The rest of the time there are no failures.

Important! How to add pressure in a gas boiler in this case. just block the hot water supply crane.

If after that the pressure does not restore, you need to look for the cause in another place.

Air in the system

The first launch of the system with cold coolant is always accompanied by air accumulation. As a rule, working air vents are able to cope with this problem. However, the device for air removal can fail. The reason for this is the boiled passage hole or distorted float of the device.

To determine the dumping of the system, you need to turn off the loudly working devices and walk along the entire circuit, carefully listening to extraneous sounds. If a characteristic gurgle is heard, with almost 100% confidence it can be argued that air has appeared in the pipeline.

How to quickly remove air from the heating system yourself, is shown in the video

How to increase pressure in a gas boiler if an air cork is detected:

  • Before starting work, turn off the gas boiler.
  • It is most convenient to steal air through the crane of Maevsky. It is located from the end of the radiator.
  • To release air, use a special key-butter, which comes with heating batteries. In its absence, you can use a slotted screwdriver.

After removing air traffic jams, to raise the pressure, you need to fill the circuit with a new portion of the coolant. During the filling, it is necessary to enable the circulation pump. As soon as the manometer shows the necessary values, to re.drop the air until it completely retires.

Important! If this operation has not helped, it is necessary to remove the coolant from the system and replace the damaged air carrier.

The expansion tank is faulty

main destination Expensulating tank. This is a hydraulic compensation of the system with physical expansion of water due to its heating by a heating boiler. The design is a tank divided in two rubber membrane. The upper chamber is filled at the plant with a special gas, the lower one is a compensator. It is there that the excesses of the expanded liquid enter.

If the cause is its malfunction, first of all you need to pay attention to the nipple. Worn gum leads to air passing and reducing pressure.

How to raise pressure on the boiler with malfunctions of the expansion tank:

How to Repair a Leaking Boiler Relief Valve Easy DIY

  • First you need to try to download air into the upper half of the tank using a pump.
  • If the hiss continues, one thing remains. to completely replace the nipple.

about other reasons for the fall in the pressure in the heating system and ways to eliminate them in the video

Briefly about the main thing

Having studied some possible causes of pressure falls in the boiler, it must be said that the parameters in the system are not always emergency. So, during commissioning, a cold coolant is used, which causes the formation of air plugs in need of discharge. It is during this operation that the pressure is reduced.

If, after the verification, there were no coolant leaks, the expansion tank and the reset are working, and the pressure is still observed in the system, it is necessary to contact the service service so that the work is carried out by professionals.

You faced the fact that the pressure in the boiler fell? What was it connected with and whether it was possible to solve the problem?

The reasons for the fall in pressure and the methods of its restoration

Reducing pressure leads to a decrease in water level in equipment, since it is not able to get into it. Accordingly, when the pressure in the Navien boiler drops, its automatic shutdown occurs.

To reduce the likelihood of stopping equipment, it is necessary to regularly maintain maintenance. At this time, they diagnose the boiler device and, if necessary, replace the failed parts.

The heating of the room occurs due to heat of water or other coolant, which is heated in the boiler and circulates through the system. The movement of water along the closed heat circuit of the building is carried out due to the pressure created circulation pump. When this parameter is reduced, the speed of moving the coolant through the system is reduced. The heat of heat does not stop, but in most cases it is concentrated at any one point of the circuit.

Termination of electric power supply

One of the most common reasons why the pressure in the gas boiler Navien Deluxe and other models falls is disconnecting power supply. In this case, the operation of the equipment stops.

You can correct the situation and avoid its repetition if you establish an alternative source of electricity. Often choose batteries and different sources of uninterrupted nutrition. They need to be constantly charged, otherwise it will not be possible to provide continuous power supply of thermal equipment.

Attention! If the pressure in the gas boiler Navien drops and it is not restored for a long time, there is a probability of defrosting radiators. In this case, it will be necessary to carry out expensive system repair.

Leakage in the heating circuit

With a frequent pressure reduction, it is worth checking the elements of the heating system for the presence of leaks. First of all, you need to watch radiators, locking reinforcement, pipelines, etc.

The leak is not always easy to find. Puddles and a coolant fountain occur in a serious accident, and in this case the pressure instantly drops. In most cases, the leakage is small drops of the coolant or a wet place of connection, which quickly dries.

If the coolant drips, the pressure in the system decreases slowly. To solve this problem, many homeowners begin to constantly feed the contour. But in fact, this is not a solution, but damage to radiators. In new portions of water there are oxygen and various impurities. They react with the equipment, as a result, scale is formed.

Important! Navien boilers are equipped with low pressure protection. They stop working, and the user must timely determine the cause of the malfunction.

Often a leak is formed in places of connection of pipes to fittings. The coolant can also be seen on traffic jams. If water seeps from the system, salt stains and rust appear in such places, but these signs depend on the composition of the coolant.

water can drip in places where radiators are connected. The reason is metal corrosion. At the same time, not only cast.iron, but also bimetallic and aluminum batteries proceed.

Attention! During the search for a leakage site, it is recommended to carefully inspect all the batteries at the facility.

To facilitate the search for leaks, experts advise if possible to turn off heating for a short time. As soon as the radiators cooled, the system needs to be turned on and put on the pressure of 2.5 barra. This will quickly detect the leak on the floor in the form of drops or puddles.

Котел Buderus GB064-24KD меняем температуру горячей воды в летнем режиме работы.

Boiler. one more place of possible leaks. Flow can be formed in the heat exchanger and in places of various connections. If the leak is small drops, then they cannot be seen in the boiler, since they quickly evaporate in working equipment. It will be possible to determine the faulty element only with a more active leak.

The coolant can also leave the system in case of violation of the tightness of the safety discount valve or the tap. It is easier to find a leak in these places, even if the burner works.

A malfunction of the expansion tank

If there is no coolant leak, the reason for reducing pressure in the system may become expansion tank. This container for Navien and any other boiler is a closed tank. It is also called an expansomate.

When heated, the volume of the coolant increases by about 0.3% per 1 liter. Because of this, the pressure in the heating circuit increases, and the expansion tank regulates the pressure in the circuit and takes the excess water into itself. After cooling, the water from the tank returns to the system.

Determine that the expansion tank is the cause of pressure reduction, simply. The indicator begins to grow when the coolant heats up. At the same time, this parameter is reduced to emergency value in the compensator tank. This is due to a special valve. As soon as the coolant is cooling in the heating circuit, the pressure becomes below the required.

boiler leaking water from pressure relief valve

buderus, boiler, drops, water

To correctly adjust the compensator, you need to follow the instructions that are included in the kit of the tank. In it you can find the value of the required pressure. Then you need to reconfigure the expansomate as follows:

  • Gleam the boiler through the drain fitting.
  • Lower the air from the expansion tank through the nipple.
  • Connect the pump to the tank and upload air until the pressure in the container reaches 1.5 bar. During manipulation, a coolant can flow from the expand through the fitting. This is fine.
  • Re.removing air.
  • Again pump air into the compensator to the values ​​indicated in the instructions.
  • Block the drain fitting.
  • Open the valves and filing taps to fill the system.

Briefly about the main thing

There is natural gravitational and dynamic pressure. For the Navien boiler, a working indicator is an important 1.5-2 bar. It is controlled using a pressure gauge.

buderus, boiler, drops, water

A drop in pressure can occur due to the occurrence of leaks in the thermal circuit. It needs to be found and eliminated. Another reason is a prolonged shutdown of electricity, so a reserve power source is often installed.

In the boiler itself, the reason for reducing pressure can be an expansion tank. It is pumped after draining the entire coolant. The pressure in the system is still reduced due to air plugs or failure of the safety valve. In the first case, the air is removed through the descents, and in the second. a new part is installed.

Have you encountered the pressure in the gas boiler? Was it possible to solve the problem and how?

Norm and control

The heat supply system adversely affects both excessively high and low pressure measured in the atmospheres. over, the normal level is 1.5-2 atmospheres.

Is Your Central Heating System Losing Pressure?

Healthy! In multi.storey buildings with central heating, this norm is slightly higher, since here the pipes should withstand hydraulic shocks.

Types of pressure in the system

In double.circuit heating systems, the pressure is divided into the following types:

  • static. is formed under the influence of gravitational forces on the coolant; rises by 0.1 bar with an increase in height by one meter;
  • dynamic. created by forced operation of the pump unit or an increase in temperature when moving the working environment;
  • working. static uniform;
  • Excessive. the difference between atmospheric and measured;
  • Absolute. excessive atmospheric;
  • nominal. indicated by the manufacturer in technical documents for a gas boiler;
  • maximum. maximum permissible, threshold value that the device is able to endure;
  • maximum (assressing). a value at which the device is tested; may exceed the working level one and a half times.

Control devices

Gas boilers contain various components responsible for the regulation of equipment parameters and maintaining it in working condition. This system requires constant monitoring of the functioning of the system. To control fluid pressure, pressure gauges and thermomanometers are used.

Interesting! Thermomanometers allow to additionally control the temperature level.

In some systems, instead of conventional arborers, electronic sensors are used. The sensors transmit the received information to the electronic unit, which processes them and displays them on the screen.

Water pressure control is provided by the sensor installed in the system. manometer

If there is no manometer in the heating unit, then it is provided for a security group, which consists of the following components:

  • The manometer itself or thermomanometer itself.
  • Air descent to ensure an obstacle to the disgrace of the circuit.
  • A safety valve for dumping the pressure of the coolant with its strong increase.

Reasons for a drop in pressure and solution options

A pressure drop can adversely affect the normal operation of the heat supply system. In this situation, water stops entering the unit, and it automatically turns off. Therefore, it is important to provide timely maintenance, inspection and repair.

The causes of pressure falling can be different, consider the most common of them.

The pressure in the system drops when hot water is turned on

This problem is a fairly common. This phenomenon is explained by the special design of boiler rooms.

According to experts, that in reality it is just a manometer reflects incorrect meaning. The pressure of the pressure can contribute to the air leaks in the circuit or the incorrect operation of the three.way valve.

For information! If when opening a tap with hot water, the normal operation of the system is not restored over time, then the pressure is reduced, and the problem really exists.

Pressure drops due to leaks

To eliminate this type of malfunction, the owner needs to diagnose and inspection of the entire heating system, since the liquid can go through any node.

The cause of the leak may be a loosely clamped connection, the wear of heat exchangers, cracks in pipes and batteries. Most often, the tightness level is checked when the circuit is launched into operation, however, the tightness can violate during operation itself.

Nodes that need to be inspected and checked in the first place:

The discovered problems must be eliminated, after which the system will be fed with liquid until the normal pressure level is restored.

Air traffic jams

The formation of cracks and depressurization of the heat supply system leads not only to leaks, but also to the opposite effect. suction of air masses in the outline. The result of this is the formation of air bubbles.

Reduced pressure can occur due to air traffic jams

Bubbles are also formed with incorrect filling of the circuit, so air traffic jams appear in it, causing a significant drop in pressure.

Recommendation! This problem is solved through ordinary defaulting the system, thanks to the installation of descent.

Explanatory tank problem

There are cases of problems with expansion tanks. A gap is formed here or the nipple can pass air. The inner side of the tank consists of two compartments separated by a membrane. There is air in one department, and the other is filled with the coolant. When heated by a liquid working environment, its expansion occurs, and it presses on the membrane with greater force. The membrane, in turn, affects the compression of the gas mixture.

Когда оборудование функционирует длительное время, ниппель изнашивается и начинает пропускать воздух, что и приводит к снижению давления.

The problem with the expansion tank can cause pressure change

The only resolution of this malfunction is the complete replacement of the tank, however, before that, you should make sure that the problem lies in this, and not in the leak of pipes, radiators and bullying the system.

Malfunction of measuring equipment

Sometimes the diagnosis of the system for the integrity of its component components may not give results. If you have not been able to detect a visible reason, then you should think about checking the serviceability of the boiler automation and instrumentation equipment. This equipment may break and give out incorrect readings.

It is quite difficult to determine this type of malfunction yourself, so it is better to seek help from specialists. The problem is solved by replacing instrumentation.

Cracks on the heat exchanger in the boiler

On the walls of heat exchangers, after time, microcracks can form that pass water from the heat supply system. Since the water in the boiler quickly evaporates, this breakdown is identified by ourselves in the same way as in the previous situation, not just. In addition, cracks can occur during washing, which is carried out for prevention or due to factory marriage. This problem is eliminated due to the sealing of the detected area with a crack.

In the walls of the heat exchanger, microcracks can lie over time

The heat carrier discharge valve is not closed tightly

Sometimes the reason may lie in a very simple moment, such as an insufficiently tightly clamped crane, due to which the pressure level in the aggregate decreases. The problem is eliminated easily and quickly twisting the crane.

Prevention of problems with manometer indicators on the heating ring

So that during the operation of equipment, to avoid the question: “The pressure in the boiler falls. what to do?”. from time to time, the prevention of the system’s performance should be carried out. These measures are the following operations:

  • Periodic check of connections, fittings and other elements of a closed circulation circuit circuit.
  • Inspect the performance of ball valves, descent valves, automatic air vents, in order to identify the contour depressurization in time.
  • Check the exhibited boundary conditions on the protection and automatic control module for the work of equipment.
  • Control the quality of the coolant, install the reverse osmosis system to clean water coming from the node. This will help to avoid the deposition of scale and overgrowing of pipes.
  • Conclude an agreement with the service service that will conduct periodic maintenance with minor repair work and replacing the worn units of the unit. If the pressure in the gas boiler drops, the reasons are not clear, you should immediately contact representatives of the service, which will arrive in place and eliminate all problems.

It should be noted that if the pressure in the gas boiler does not rise, this indicates an already formed problem that was brewing over a long time. The best solution would be to prevent the formation of defects, which will reduce the risks of equipment failure.

Briefly about the main thing

If you need to find out why the pressure in the heating boiler drops, the entire circuit should be inspected for identifying possible leaks in the system. Also, the drop in the testimony of the pressure gauge is possible with a malfunction of the membrane tank or failure in the automatic settings of the protection module. If the pressure in the heating boiler drops, the causes are clear, you can fix the problems yourself. Когда действия владельца доме ни к чему не приводят и усугубляют ситуацию, либо если оборудование всё ещё на гарантии от производителя, следует обратиться за помощью в специализированные организации.

You had to wonder why the pressure in the heating boiler in your house fell? Tell us how you managed to identify the reason for this and eliminate it.

Preparation of water for the heating system

The higher the stiffness of the water, the worse it is for heating. the scale leads to overgrowing of gaps in pipes, disables the heat exchangers of the boiler and kills the pumps.

Cleaning the system from scale is an extremely difficult task for several days. It’s easier to make efforts once to correctly prepare a coolant for heating.

Soft water is not everywhere, but hard water can be softened at home before pouring it into the system. For this, special filters are purchased. softeners.

To try too hard, softening water, it is also not necessary in a soft liquid, higher acidity, and this leads to the release of carbon dioxide and metals corrosion. High acidity also in antifreeze with glycol in the composition. The additives. inhibitors (silicates, amines, phosphates and others) help reduce its harmful effects.

Good acidity: 8.5. 9.5 pH.

Recipe: you can mix tap water with distilled, in a ratio of 1: 1.

After mixing, the resulting liquid is required to boil (to remove oxygen from it).

Do not use chemical additives to soften water.

Their use destroys the seals, and when heated, processes occur, destructive even for metals.

So, if the pressure rides or stably low, the search for the problem must be started with the inspection of the pipeline for leakage. Then check the performance of the pumps, measuring static pressure. In order not to re.encounter a problem, everywhere you need to install air vents and do not regret the strength to prepare a coolant with optimal pH.

How to avoid air entering the heating system

It is very difficult to completely avoid getting into the air system, but you can minimize the problem and learn how to easily and quickly eliminate traffic jams:

buderus, boiler, drops, water
  • It is necessary to monitor the serviceability and tightness of all joints, shut.off valves, etc. D.
  • Before starting the system, it is pumped into it with a compressor under pressure by 20 % more than working. Measurements from the pressure gauge are removed at the beginning of the dough and after 20 minutes. If the indicator has not changed, there is no leakage, the system is sealed. The arrow of the manometer, as well as a characteristic whistle, will say about the leak. To finally make sure that the leakage place was found, it is lubricated with a thick soap solution.
  • Fill the system with cold water and smoothly. After filling, the air is lowered several times using air vents and crane cranes. Each time after descent into the system, water is added.
  • It is recommended to use stainless or bimetallic heating radiators.
  • It is also advised not to change the coolant too often. In a fresh portion of water, there are always impurities of oxygen.
  • To describe the air, install air vents in all problem areas and regularly use them. Or supply radiators with automatic devices and monitor their serviceability.

The adaptive period of the system, during which you need to again and again lower the air and add water. several days.

Why the fall happens. the main reasons

It happens that when hot water is turned on, the pressure in the boiler drops and it turns off. Sometimes they do not pay attention to this, they simply periodically feed the system. But such measures help only for a short time, it is better to immediately determine the root cause of the breakdown. At the same time, it is not at all necessary to contact specialists: in most cases, it is possible to independently find and eliminate the reason why the pressure drops in the dual.circuit boiler when the hot water is turned on.


In modern heating structures, pipes from stitched polyethylene or polypropylene are used. Cracks on them are rare. But radiators, heat exchanger in the boiler can crack: water will begin to leave, the subteids will appear. Repair of the sectional battery of large expenses does not require. It needs to be removed, promoted, replaced by the broken section. The panel product will have to brew or change completely.

  • Remove the front cover.
  • Carefully inspect the radiator. At the place of formation of the crack, the metal is oxidized, it acquires a greenish color.
  • If a defect is detected, the damaged part must be replaced.

A leak

  • Disconnect the boiler.
  • Wait until the system cools down.
  • On the heating batteries, block the taps.
  • Increase pressure to 1.5 bar.
  • Turn on the heating device.
  • Check each wing alternately. If the pressure falls, then the reason is in the pipes or the heating unit. Under other circumstances, one after another you will have to open the cranes of heating radiators to detect a leak in one of them.

Famous crane

Filling the heating contour is performed using a sub.time tap, which connects the water supply to the boiler. When users forget to close it, the pressure is often reduced, and therefore the pressure in the gas boiler drops when hot water is turned on. If the heating unit is double.circuit, the effect of communicating vessels occurs. When hot water supply is not used, the pressure is kept within normal limits. As soon as the mixer opens, it drops sharply. This happens for the reason that the water from the contour goes into the water supply. It is possible to detect such a problem by the unpleasant smell of the coolant. In case of serviceability of the sub.time, it will only be enough to close it, otherwise it will have to be replaced. The correct installation of heating units requires the installation (at all outputs, inputs) of ball valves. Because if the water is not used, the latter can simply be closed. This will be quite enough for a short.term solution to the problem. The video will help to deal with the problem associated with the fact that when the DOS is turned on, the pressure in the heating system of the double.circuit boiler drops

Expansion tank

A violation of the integrity of the membrane in the tank may lead to a decrease in pressure. Most often this happens with flat tanks that are used together with hinged boilers. This damage occurs as follows: in the summer, the diaphragm sticks to the walls, and in the fall, after turning on the heating, it just breaks. In this case, it will have to replace it or purchase a new tank. Excessive growth or drop in pressure after heating can occur due to improper selection of an expansion tank. The volume of the latter should be 1/10 of the amount of water inside the system or 1/7, if antifreeze is used as a coolant.

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