Causes of rising pressure. Ways to solve the problem
To understand that there is too much pressure in the system, you can use the pressure gauges. Normal readings are 1-2.5 bar. If the pressure gauge needle reaches 3 bar, sound the alarm. If the increase is constant, it is urgent to find the cause and reduce the pressure.
Also pay attention to the safety valve: to relieve pressure, it will constantly emit water
Expansion tank issue
This tank can be located separately from the boiler or be part of the structure. Its function is to take excess water when heated. Hot liquid expands, it becomes 4% larger. This excess is sent to the expansion tank.
The size of the tank is affected by the power of the boiler. For gas equipment, its volume is 10% of the total amount of coolant. For solid fuel - 20%.
Membrane rupture. If the part is damaged, the coolant is not restrained by anything, therefore it completely fills the compensation tank. Then the pressure starts to drop. If you decide to open a tap to add water to the system, the pressure will rise above normal. The connections will leak.
The tank or diaphragm needs to be replaced to reduce the pressure.
The pressure is below or above normal. A machine pump will help to achieve normal values \u200b\u200b(nominal value) in a gas boiler.
- Drain all water from the system.
- Close the valves.
- Pump the circuit until you are sure there is no water.
- How to release air? Through the nipple on the other side of the supply.
- Download again until the indicators reach the norm specified in the instructions for Ariston, Beretta, Navien and other brands.
The location of the tank after the pump provokes water hammer. It's about how the pump works. When it starts, the pressure rises sharply, and then also drops. To avoid such problems, in a closed heating system, install a tank on the return pipe. The next to hit is the pump in front of the boiler.
Why pressure rises in closed systems
Air accumulates in a double-circuit boiler. Why does this happen:
- Wrong filling with water. The fence is from above, too fast.
- After repair work, excess air was not released.
- Mayevsky cranes for air release are broken.
The pump impeller is worn out. Adjust or replace part.
To relieve or reduce pressure, fill fluid correctly. The fence is carried out from below, slowly, while Mayevsky's taps are open to bleed excess air.
Open System Issues
Problems are the same as described above.
It is important to properly fill water and bleed air. If after that the pressure has not returned to normal, it is necessary to drain the system
Secondary heat exchanger
The unit is used to heat domestic hot water. Its design consists of two insulated tubes. Cold water flows through one, hot water flows through the other. If the walls are damaged, a fistula appears, the liquids mix and enter the heating part. Then there is an increase in pressure.
If you do not want to repair and solder the heat exchanger, you can replace it. To do this, buy a repair kit and get to work:
- Shut off supply valves.
- Drain the water.
- Open the case, find the radiator.
The assembly is secured with two bolts. Unscrew them.
- Remove the defective part.
- Install new gaskets in the mounting points and connect the heat exchanger.
Other reasons
There are other reasons for such problems:
- Armature closed. During the intake, the pressure rises, protective sensors block the equipment. Inspect the taps and valves, unscrew them until they stop. Make sure the valves are working.
- Clogged mesh filter. It is clogged with debris, rust, dirt. Remove and clean the part. If you don't feel like cleaning regularly, install a magnetic or flush filter.
- The feed faucet is out of order.Perhaps its gaskets have worn out, then you can get by with a replacement. Otherwise, you will have to change the valve.
- Automation problems. Faulty thermostat or controller. The reason is wear, factory defects, incorrect connection. Diagnostics and repairs are underway.
Check whether the boiler protection parts are in good condition: pressure gauge, valve, air vent. Clean radiators and other components from dust, soot, scale. Prevention helps prevent serious damage to gas equipment.
pressure drop
The increase in pressure in closed heating systems is not the only problem, in some cases there is a sharp drop in operating pressure, while among the reasons why the pressure level drops are the following:
- hidden system leaks, corrosion, loose connections, fitting leaks;
- rupture of the tank membrane, which requires replacement or repair of equipment;
- pressure drops in the system are observed if the nipple poisons, such an air leak leads to the tank being blown off, and this causes damage to the membrane;
- there are cracks on the boiler heat exchanger, which leads to leakage of the coolant;
- pressure drops associated with the appearance of air bubbles lead to a decrease in the overall temperature in the system and its stop;
- one of the reasons for a decrease in pressure may be a soured or ajar faucet used to discharge water into the sewer system.
How to increase the pressure in the boiler
If the pressure drops due to the expansion tank, then its volume is incorrectly calculated or the inner membrane is damaged. The situation is corrected by a more accurate calculation of the required volume or by replacing the tank.
If the pressure in the heating system drops immediately after its first start, then this is the norm. In a freshly filled circuit, if it was filled with ordinary tap water, there is a lot of air. As soon as it is converted to bubbles and removed from the pipes, the parameters of the circuit are normalized. You can also try removing bubbles manually using a manual air vent.
Worst of all, if the pressure has dropped in a system laid inside walls and floors - pipes are often masked and completely recessed into building structures. If something happens to them, you will have to suffer thoroughly in order to localize the malfunction. The situation can be prevented by a more careful choice of materials for the construction of the heating circuit.
Before increasing the pressure, it is necessary to check the tightness of the system. To do this, you need to look at:
- All heating appliances - often leaks form where they are connected to pipes. Leaks between individual sections are also possible;
- Pipes - microcracks often lead to leakage of the coolant, due to which the pressure gradually drops;
- Fittings are another common place for coolant leakage;
- Boilers - double-circuit models have a complex internal structure; it is necessary to inspect the circulation pump, three-way valve and heat exchanger.
It is best if a specialist will inspect the double-circuit boiler.
Increased pressure in the heating system causes an imbalance in the operation of the equipment, frequent blocking of the boiler. As a result, individual elements are subjected to increased stress, which leads to circuit breakage and equipment failure. Why does the pressure in the heating system increase? There are several reasons for this phenomenon, most often these are leaks, an imbalance in the operation of individual elements, a failure in the operation of automation, or incorrectly performed settings.
Norm and control
We have already said that in a gas boiler the pressure should be within 1.5-2 atmospheres - this is the norm for a system that is put into operation and is in a heated state. In multi-storey buildings heated by centralized boilers, this figure is higher. Here, pipes and batteries must withstand not only high pressure, but also water hammer - this is an abrupt increase in pressure.
If drops are typical for centralized systems, then they are rare for autonomous heating - the volume of the coolant here is not so large that serious jumps are observed. In the cold state, the normal indicator is 1-1.2 atm., And in the heated state - a little higher.
In private households, autonomous heating systems are used, powered by single-circuit and double-circuit boilers. The latter are becoming more and more common. In addition to heating, they solve the problem of preparing hot water. One circuit in them heats the coolant circulating through the pipes, and the other ensures the operation of the hot water supply system.
If there is no expansion tank
The expansion tank for the domestic heating network is the second most important element (after the boiler). Water, when the temperature changes, changes in volume. The volume inside the circuit is always constant, therefore, an expansion tank is additionally connected to the circuit, where excess coolant can be diverted, i.e. acts as a compensator. Therefore, RB is a fuse device that prevents emergency situations - pressure increase, pipe depressurization, etc.
The use of boiler equipment without an expansion tank is highly discouraged.
For stable operation, the pressure of the RB must correspond to the system in terms of volume, because. when replacing radiators with pipes, the volume of the coolant must be increased. At the same time, too large RB will not maintain the working pressure in the circuit.
The standard is an expansion tank designed for 120 liters of coolant in the circuit (typical two-room apartment). If the tank is too small, then the discharge of water during heating and expansion of the volume will be carried out through a safety valve. When the boiler is switched off, when the temperature of the liquid decreases, it will not be possible to start the boiler, because its volume, and, consequently, the pressure will be insufficient. In such cases, additional feeding of the network is necessary.
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Best Answers
lover:
You must have a descender, an air vent. Put a hose on it so as not to get wet, and quietly opening the tap - try to relieve pressure. (This is my opinion, but it is better to call a specialist.)
Boss Heat:
In any place of the heating system where there is a drain tap (Mayevsky tap, drain on the battery, etc.), open and pour into a jar or bucket. It is most convenient to turn the relief valve on the wall-mounted boiler.
Eliseikin:
Look for a drain valve .. there must be!
alexm66:
The boiler has a drain cock (usually at the bottom). It is usually opened with a key - there is no flywheel on it. The instructions for the boiler indicate its location. In this case, it is desirable to stop the boiler.
Here I say:
Before releasing the pressure, check that the valve to the expansion tank is open. If it is closed, open it, the pressure should decrease. If it was open, bleed in any convenient place from the battery. In no case do not bleed the pressure from the boiler safety group yourself - if a speck gets under the valve seat, it can be very difficult to wash it off - this is how the valve drips.
Victor:
Put an expansion tank and forget about pressure surges.
L@rchik:
Bleed the air from the radiators, the pressure will immediately decrease. Do not climb into the debugged mechanism (boiler).
What can plugs in the circuit lead to
The importance of air outlets cannot be overestimated. Plugs in the circuit can lead to different processes:
- circulation disorder;
- pressure surges;
- decrease in the efficiency of heating equipment;
- corrosion of metal.
Autonomous air vent
Installing an air vent in the heating system prevents the formation of plugs and pockets. Bumping into them, the coolant stops. Sometimes plugs cut off entire segments with radiators from the circuit. In this case, the pressure in the system increases. When it reaches a critical level, an emergency release of the coolant occurs. This in turn leads to a drop in pressure.At the same time, there are many cases when air was collected in the batteries, the circuit continued to work, only half of the radiator became cold. This significantly reduces the efficiency of heating and slightly increases the cost of its operation.
For open systems, one of the most serious threats is rust. At the same time, the question of how to remove air from the heating system arises only at the design stage. Such circuits are assembled at an angle from pipes with a large diameter, respectively, there is a lot of water in the system. Given the fact that the coolant comes into contact with air and draws it into circulation, the oxygen level in the pipes is more than sufficient. Since it takes a long time to bleed air from the heating system, oxygen reacts intensively with the metal. The result of the interaction is the formation of corrosion on the inner walls of the pipes. Rust sometimes eats up the tank so much that you have to change it.
The direct consequences of traffic jams in the circuit entail indirect, which are no less dangerous:
Occurs if the valve for bleeding the air from the heating system and all sensors are working and working correctly. Due to the increase in pressure, an emergency release of the coolant occurs, which leads to a decrease in its amount in the circuit. After cooling, the fluid in the system will not be enough, the pressure will drop sharply. If it does not correspond to the minimum required to turn on the boiler, the heater will not turn on accordingly. And from this moment in winter, the countdown begins when the pipes are defrosted. Depends on how insulated the house is. Sometimes it happens in just three hours. In this case, unpleasant news awaits at home from work;
This happens if there is a malfunction in the valve for bleeding air from the heating system, or in the equipment that controls the temperature. An unlikely situation, although possible. The results of this are very deplorable. At best, repair or replacement of the boiler, at worst - injury;
rupture of the circuit and the release of a hot water fountain.
A very likely situation, the joints may not be tightened enough. When the pressure increases, they do not withstand and give a crack. At the same time, hot coolant flows from the pipe, like a fountain. Not only does the circuit need to be repaired, but the neighbors also need to do the ceiling, since you filled it in order. This is the kind of chain that a simple airing of the system can cause.
The optimal value for a private house or cottage
Any boiler operates under certain system settings, in particular, it is necessary to correctly calculate the water pressure. This value is affected by the number of storeys of the building, the type of system, the number of radiators and the total length of the pipes. Usually, for a private house, the pressure level is 1.5-2 atm, but for a multi-apartment five-story building, this value is 2-4 atm, and for a ten-story house, 5-7 atm. For higher buildings, the pressure level is 7-10 atm, the maximum value is reached in heating mains, here it is 12 atm.
For radiators that operate at different heights and at a fairly decent distance from the boiler, constant pressure adjustment is required. In this case, special regulators are used to reduce, and pumps are used to increase. But the regulator must always be in good condition, otherwise sharp fluctuations and drops in the temperature of the coolant will be observed in some areas. Correction of the system must be carried out so that the shut-off valves are never completely closed.
Control devices
Pressure gauges and thermomanometers are used to control the water pressure in the heating boiler and heating system. The latter are combined devices for controlling two parameters at once. After starting the circuit, it is necessary to monitor the indicators so that they do not go beyond the norm.
Some double-circuit floor and wall boilers do not have traditional dial gauges.Instead of them, electronic sensors are installed here, the information from which is transmitted to the electronic unit, after which it is processed and displayed. Another approach is also possible - if the heating unit is devoid of a pressure gauge, it is provided for by the safety group.
The security group itself includes the following nodes:
- Pressure gauge or thermomanometer - to control the temperature and pressure in the heating circuit;
- Automatic air vent - prevents airing of the circuit;
- Safety valve - relieves the pressure of the coolant when it is excessively increased.
Be sure to provide this node in a closed heating system.
Constantly rising pressure
Posted by Bahus » Oct 22, 2013, 10:37 am
Posted by garry » Oct 22, 2013 6:29 pm
Post by Bahus » 22 Oct 2013, 20:34
Posted by AlexanderTambov » Oct 23, 2013, 09:46
Post by Bahus » 23 Oct 2013, 10:27
Posted by Bahus » Oct 23, 2013, 10:39 am
Posted by AlexanderTambov » Nov 03, 2013, 09:15
Post by Anatolii » Nov 03, 2013, 09:36
Posted by RADAR » Nov 03, 2013, 09:55
Posted by AlexanderTambov » Nov 05, 2013, 21:36
Post by BAXI-Ural » Nov 05, 2013, 21:40
Post by Sergey L » November 06, 2013, 14:07
And how to get rid of it? Automatic air vents?
I have a similar problem: Baksi EcoFor 240F boiler, house 2 floors, 130 m2, two-pipe polypropylene system, Raden 500 aluminum radiators, air accumulates in the radiators of the 2nd floor, I bleed through the Mayevsky taps, the pressure drops, sometimes I have to recharge. Not often, but still not good. There are no leaks. Climbed everything.
Post by BAXI-Ural » 06 Nov 2013, 15:41
Posted by AlexanderTambov » Nov 06, 2013, 04:49 PM
Posted by Bahus » Nov 06, 2013, 06:08 pm
Posted by sergey 73 » Nov 07, 2013, 10:24 am
Post by BAXI-Ural » 07 Nov 2013, 10:47
Post by Alex-BAXI » 07 Nov 2013, 11:05
head of condensing equipment, representative office of BAXI in the Russian Federation
Post by BAXI-Ural » 07 Nov 2013, 11:40
Posted by RADAR » Nov 07, 2013, 13:09
Post by DmitryTambov » Nov 25, 2013, 20:51
Posted by BAXI-Ural » Nov 25, 2013, 21:15
Post by RADAR » Nov 25, 2013, 21:39
Post by DmitryTambov » Nov 26, 2013, 23:39
Post by BAXI-Ural » Nov 27, 2013, 06:20
Posted by DmitryTambov » Nov 27, 2013, 20:11
Posted by RADAR » Nov 27, 2013, 20:16
Post by DmitryTambov » Nov 27, 2013, 20:22
Posted by RADAR » Nov 27, 2013, 20:40
What about the power limit? And as for gas, it can be like that. And about the description, too, I may be mistaken because the thermometer can show a different value, well, by 10-15 degrees. today I'm going to put an additional pump on the return line of the satellite, will it help?
Sent after 1 minute 41 seconds: and I can turn off the power limit myself because there are no specialists in gas boilers here. And about the max temp of 85 is that all but higher in any way?
I'm interested here. Those with the phrase in the title drops the pressure on the forum a little more than a damn thing. Do people not use search? Or do they think that they have a super-special boiler, in which this problem is solved in a very specific way? Lord owners. Appreciate the time. Both his own and the service workers. Closed.
Sent after 3 minutes 42 seconds: Nate. Too lazy, damn it, to think again with your head. We want to save money, but we don't want to think.
Twenty, motherfucking, six topics with the same reason. And that's just in.
How to bleed air from the boiler
Modern heat sources are equipped with automatic air blowers or Mayevsky cranes located in the upper part of the unit. Such a constructive solution allows you to bleed air during the operating mode, without stopping the process of heating the room, just like from any radiator on which such a valve is installed.
To do this, periodically open and close the Mayevsky tap, with an interval of several minutes. The procedure is repeated until a hiss or whistle appears, indicating the release of an air lock. The appearance of sound requires holding the bleed device in the open position until the coolant appears.
The absence of special devices for removing plugs on the boiler requires the use of the same devices on pipelines located above the heat source.
The ideal conditions for releasing the air lock in the boiler is the possibility of a separate blocking of the heat source circuit with a return pipe and a circulation pump.When turned on, the pumping of the coolant is ensured, and the periodic opening of the Mayevsky tap or control over the operation of the automatic air vent, by pressing the spool, allows you to release the blocked circuit from the plug.
If there is no circulation pump in the closed circuit that cuts off the boiler with a return pipeline, then the energy source is turned on: gas, electricity, and in the solid fuel one, the furnace is ignited. After heating the "supply" pipeline, the air blower is periodically opened. The heat carrier, heating up, will rise from the boiler along the main line due to heating and return through the connecting pipeline - back to the heat exchanger. This technique requires careful monitoring of temperature, especially when servicing a non-solid fuel heat source. The movement of the coolant along such a circuit will be very slow and this is taken into account when performing work.
If it is not possible to shut off the water circuit of the boiler and there are devices for air removal only in the upper part of the line, it is necessary to drain the coolant, and then fill in the entire required volume of water. Before proceeding with such global events, it is recommended to cut off all devices (except for the boiler) and, turning on the pump, bleed pressure through the nearest air vent on the line until sound or bubbles appear. The absence of a result indicates the need for a complete drain of the coolant.
Pressure increase due to expansion vessel
Increased pressure in the circuit can be observed due to various problems with the expansion tank. Among the most common causes are the following:
- incorrectly calculated tank volume;
- membrane damage;
- incorrectly calculated pressure in the tank;
- improper installation of equipment.
Most often, a drop or increase in pressure in the system is observed due to a too small expansion tank. When heated, water increases in volume by about 4% at a temperature of 85-90 degrees. If the tank is very small, then the water completely fills its space, the air is completely bled through the valve, while the tank no longer performs its main function - to compensate for the thermal increase in the volume of the coolant. As a result, the pressure in the circuit is greatly increased.
To solve this problem, it is necessary to correctly calculate the volume of the tank, which should be at least 10% of the total water volume in the gas boiler circuit and at least 20% if a solid fuel boiler is used for heating. In this case, for every 15 liters of coolant, a power of 1 kW is used. When calculating the power, it is necessary to determine the volume of the heating surfaces, for each individual circuit, which allows you to get the most accurate values.
The cause of the pressure drop may be a damaged tank membrane. At the same time, water fills the tank, the pressure gauge shows that the pressure in the system has dropped. However, if the make-up valve is opened, the pressure level in the system will be much higher than the calculated working one. Replacing the membrane of the balloon tank or completely replacing the equipment if a diaphragm tank is installed will help to correct the situation.
A malfunction of the tank becomes one of the reasons why a sharp drop or increase in operating pressure is observed in the heating system. To check, it is necessary to completely drain the water from the system, bleed the air from the tank, then start filling the coolant with pressure measurements in the boiler. At a pressure level of 2 bar in the boiler, the pressure gauge installed on the pump should show 1.6 bar. At other values, for adjustment, you can open the shut-off valve, add water drained from the tank through the make-up edge. This method of solving the problem works for any type of water supply - upper or lower.
Improper installation of the tank also causes a sharp change in pressure in the network.Most often, of the violations, the tank is installed after the circulation pump, while the pressure rises sharply, and a discharge is immediately observed, accompanied by dangerous pressure surges. If the situation is not corrected, then a water hammer may occur in the system, all elements of the equipment will be subjected to increased loads, which adversely affects the performance of the circuit as a whole. Reinstalling the tank on the return pipe, where the laminar flow has a minimum temperature, will help to solve the problem. The tank itself is mounted directly in front of the heating boiler.
There are many reasons why there are sharp pressure surges in the heating system. Most often, these are incorrect installation and errors in calculations when choosing equipment, incorrectly made system settings. High or low pressure has a very negative effect on the general condition of the equipment, so measures should be taken to eliminate the cause of the problem.
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