Why does the pressure in the boiler drop??
If there are faults, the whole system can suddenly fail or cease to function. Even with proper installation, this sometimes happens. Thus, there may be a drop in values, after which the room is no longer heated.
Pressure drops in the boiler can occur for the following reasons:
- Breakdown of the heat exchanger. One of the most frequent causes of failure;
- Leakage in the circuit. Leaks can occur due to poor quality soldering of pipes;
- A manufacturing defect. The presence of any defects is most often associated with low-quality production;
- Clogging. Debris in the boiler can cause a decrease in performance and even breakdown of the entire system;
- The presence of defects. Mechanical damage to individual parts of the system can lead to malfunctions;
- Cracks. Cracks in the boiler also cause a sharp decline in performance;
- Wear and tear. Natural wear and tear of individual parts or the entire system can affect the performance.
These faults must be diagnosed and repaired on time. Diagnose the leakage will help the part through which air enters the chamber. If liquid begins to drip when you press on it, then the cause is a leak.
A leakage diagnosis is made according to certain rules. First the visible segments of the circuit are analysed and then the floor or wall is inspected (if the pipes are in the wall or under the floor). Sometimes it is possible to disconnect individual sections of the circuit one by one. This makes it easier to detect leaks.
If the pressure in the boiler is constantly dropping, then first all fittings are checked, then the tightness is examined (usually carried out before the heating season), all internal mechanisms are checked.
Unreliable readings can also be due to instrument malfunction. In this case it should be replaced with a new one. This should be done only after all the constituent elements have been diagnosed.
Decrease of pressure in the boiler is provoked by damaged parts in the expansion tank. If there are damages in the rubber, the fluid overflows into the air compartment and the pressure in the circuit is reduced.
Leaks can occur in a radiator or expansion tank. Also, the drop in values can be caused by worn seals, loose fittings, corrosion. All this does not allow the system to function fully and leads to its breakdown.
Norm and control
Both excessively high and low pressures, measured in atmospheres, have a detrimental effect on the heating system. The normal level is 1.5-2 atmospheres.
Useful at! In multi-storey buildings with central heating this rate is slightly higher, because here the pipes must withstand water hammer.
Types of pressure in the system
In two-circuit heating systems, the pressure is divided into the following types:
- static. formed under the action of gravitational forces on the coolant; increases by 0.1 bar with increasing height of one meter
- dynamic. created by forced operation of the pumping unit or increase in temperature during movement of the working environment;
- working. static and dynamic;
- excess. difference between atmospheric and measured
- absolute. excessive atmospheric pressure;
- nominal. specified by the manufacturer in the technical documents for the gas boiler;
- maximum. maximum permissible, threshold value the device can bear;
- Limit (pressure). value at which the unit is tested; may exceed the operating level one and a half times.
control devices
Gas boilers contain various components, which are responsible for regulating the parameters of the equipment and maintain it in operating condition. This system requires constant monitoring of the functioning of the system. Manometers and thermomanometers are used to control fluid pressure.
Interesting! Thermomanometers allow for additional control of the temperature level.
Electronic sensors are used in some systems instead of conventional pointer pressure gauges. Sensors transmit the received information to the electronic unit, which processes it and displays it on the screen.
If the heating unit does not have a pressure gauge, it is provided by a safety group, which consists of the following nodes:
- Manometer or thermomanometer itself.
- An air vent to prevent the circuit from becoming clogged.
- Safety valve to release the pressure of the coolant in case of a strong increase in its.
How to raise the pressure in a two-circuit boiler
Quite a common problem when using two-circuit gas boilers, when the hot water is turned on, and the pressure inside the boiler begins to drop sharply. The pressure drop is almost to zero, and warm water has a pungent smell. Sometimes it even happens that due to a pressure drop error, the heating boiler automatically shuts down. Another case. the pressure drop is observed when the water supply in the house is temporarily stopped, after which the boiler fuses do not allow it to restart. When you try to turn it on, the tank will give an error about problems with pressure, and simply will not turn on. In general, the drop in pressure in the boiler is very bad for the boiler and water supply systems, so you need to immediately diagnose the problem, and then proceed to immediately solve it. What is the matter and what you need to do, read below.
Principles of operation of gas boilers
In gas-fired boilers (GF) the heat carrier is heated up because natural gas is burned. From this process we get a lot of heat. And it follows through the heat exchanger to the heat carrier (CH). The heated DH is distributed throughout the heating network.
How To Top Up Your Boiler Pressure
A model with two circuits supplies hot water to all plumbing fixtures in the house and for the underfloor heating system.
If you find a drop in pressure in the GC, and the low indicator holds for a long time, you need to contact the professionals.
In order for the heating network to function properly, boilers must maintain a stable pressure. This way the heated DH will normally circulate throughout the network.
Reduced pressure can disrupt the entire network. The end result is a house without heat.
In the design of the GC integrates various devices for its control. They collect data on the condition of the heating network. And this data is displayed to the user.
For example, the norm pressure in a private home is considered a rate of 1.5-2 atm. A lower or higher reading indicates a malfunction of the unit.
Difficulties with the pressure in the heating network of the house are formed only in technologies where there is forced circulation.
It is almost impossible to eliminate the pressure drops by your own efforts. Be sure to call in a professional for plumbing repairs.
Pressure drop
Increased pressure in closed heating systems is not the only problem, in some cases there is a sharp drop in pressure, and among the reasons why the pressure drops, the following should be mentioned:
- hidden system leaks, corrosion, loose connections, leaky fittings;
- rupture of the tank membrane, which requires replacement or repair of the equipment;
- Pressure drops in the system can occur if the nipple is leaking, this causes the tank to deflate and this damages the diaphragm;
- cracks on the boiler heat exchanger, which leads to leakage of coolant;
- Pressure drop associated with the appearance of air bubbles, leads to a decrease in the overall temperature in the system and stopping it;
- One of the reasons of pressure decrease can become clogged or half-open tap, used for water drainage into the sewage system.
What to do if there is a pressure drop in the boiler
A sudden drop in water pressure indicates serious problems with not only the boiler, but the entire heating system. If the manometer shows that the pressure in the system is below one atmosphere, you should try to add water manually by opening the make-up valve. If after make-up the arrow of the pressure gauge continues to fall. it is best to seek help from a specialist, because further action without certain skills will only aggravate the problem.
Inspect the entire heating system for water leaks. Sometimes because of the increased pressure can not withstand the joints of pipe connections, and they begin to drip, which leads to a gradual drop in pressure. If you find water leaks it must be repaired immediately.
Invite a technician to the house to diagnose and check the expansion tank.
Main error codes
As with any mechanism, sometimes the heater fails, consider the most common error codes Westen gas boiler and figure out how to fix them.
Error e01 signals a lack of ignition, to correct this problem check the following
- The first thing to try is to restart the boiler. To do this, press and hold for a few seconds the “R” key.
- Next, try reversing the polarity in the socket. to do this, pull the plug out of the socket, relocate it.
- See if the gas valve is open. Also, if the ignition is made after a long standstill, there could be a trapped air in the gas pipes and it will need to be restarted a few times.
- Check the ignition electrode status. If necessary, clean.
Error E03. The safety thermostat ( draught sensor) has tripped.
- Inspect the integrity of the chimney duct.
- Check chimney diameter and spigot of the appliance.
- The flue duct may be blocked and there is no draught. Take a sheet of paper and place it on the chimney hole. If it is normal, the sheet should stick, but if the draught is bad, it will fall.
- There are two tubes coming from the pressostat and condensate could be building up in them. You need to disconnect and purge. Pressostat with two outlets
- There may not be enough air flow in the room, open the vent and door.
Error e10. Lost signal from the hydraulic pressostat.
- Check the pressure. it must be in accordance with the table in the manual.
- Using a dry cloth, check the entire heating circuit for leaks. If you have found it, fix it.
- Also the leakage is possible in the device itself. Remove the trim and inspect. Pay special attention to the heat exchanger.
Error e25 No fluid circulation (pump blocked).
- The circuit board is defective. Must be replaced. Westen boiler board
- Clogged filter. which is in front of the flow switch, clean it.
- Disassemble and inspect the pump itself. It may be enough to clean and flush it.
- Large amounts of scale have formed in the heat exchanger. It needs to be cleaned. It is made with chemicals containing acids. You can make a solution yourself, using citric acid and water in a ratio of 1 to 3.
After removing the heat exchanger, it is placed in a tank set on a slow fire and half filled with liquid. A previously prepared solution is then poured into the heat exchanger and left on low heat for 40 minutes. Then rinse under the tap and, if the flow is good, put it back in place.
Error f35. A parasitic flame bursts.
- Produce a restart.
- Circuit board is defective. Take it in for diagnostics or replace it with a new one.
- There is no grounding on the board in the terminal.
- Reverse the plug of the switch. Connecting the contacts of the socket
Error e97. Selected the wrong power source.
Types of pressure
The pressure in the 2-circuit (two-circuit) boiler is divided into the following types:
- static. formed by the action of gravitation, with an increase in height by each meter becomes higher by 0.1 bar ;
- dynamic. is created by the operation of the pump (the more power of the pump, the higher the dynamic pressure) or when the temperature increases;
- working. is obtained by adding the two pressures static and dynamic;
- excess. that which is fixed by the pressure gauge, this is the difference between the atmospheric and the measured;
- nominal. set according to the physical parameters of the materials of which the gas boiler units are made, when working in this range it is guaranteed the service life stated by the manufacturer;
- maximum. the maximum allowable pressure which prevents accidents and faults
- test pressure. this pressure is used to test the parts of the unit in the production, it can exceed the working pressure by 1.5 times.
Why does the pressure drop in the gas boiler: causes and ways to troubleshoot
Why is the drop in pressure in the gas boiler dangerous? The thing is that it can adversely affect the normal operation of the heating system. In this situation, the water stops flowing into the unit, which leads to its automatic shutdown. Therefore, it is important to provide for timely maintenance, inspection and repair. Now let’s consider what are the causes of pressure drop, with a detailed description of the most common ones.
Defects of the expansion tank
One of the causes of pressure drop in the gas boiler refers to problems with the expansion tank. There can be several reasons, for example: a rupture in the construction or depressurization of the plug, which caused its air leakage. If you have a boiler “Navien”, then you will need to buy a new tank, to perform the replacement.
However, before you buy it, you need to make sure that the problem is related to this factor. Do not exclude the cases of leaking pipes, radiators or heating circuit air leaks. If the diaphragm is damaged, the expansion tank no longer copes with its tasks, and the pressure level decreases. Detect this fact will help tapping on the structure (the sound will become deafening). And if you quickly press the nipple. water will spill.
The pressure in the system falls when you turn on hot water
The drop in pressure in the system when you turn on the hot water is the first and most common problem. This phenomenon is due to the special design of boiler units. According to experts, in reality, it’s just a manometer reflects the incorrect value. Pressure drop can be caused by air leaks in the system or a malfunctioning three-way valve.
The pressure drop is caused by a leak
To detect and correct this type of failure, the owner must conduct a thorough inspection and diagnosis of the entire heating system, because the fluid can come out through any node. The cause of the leak can be a loose connection, worn heat exchangers, cracks in the pipes and radiators. Most often the level of tightness is checked during the start up of the circuit. However, tightness can also be compromised by the operation itself.
The assemblies that are worth inspecting and checking first
If there is a drop in pressure due to leaks, the following assemblies should be inspected and checked:
Trapped air
This formation can be caused by a leak in the heating system. This can lead not only to leaks, but also to the opposite effect. sucking air masses into the circuit. Air bubbles form as a result. Bubbles are also formed when the circuit is not filled correctly, so there are air locks in it, causing a significant drop in pressure.
This problem can be solved by means of a bleed valve. They help release excess air from the system.
If the pressure is relieved after the first start-up, there is no need to worry about the failure of the heating system. This natural reaction is due to a large amount of air in the circuit. If the equipment is operating normally, the bubbles will escape from the piping and the circuit characteristics will stabilise. In order to deflate the bubbles it will be necessary to use a manual mechanism to bleed the air.You will need specialized equipment in order to find the source of the problem, in case the heat exchanger was damaged due to intensive use and wear and tear.
Faulty metering equipment
Sometimes, checking the system for the integrity of its constituent parts may not yield results. In this case, when it was not possible to find the cause of the drop in pressure in the gas boiler, it is worth thinking about checking the proper operation of the boiler automation and instrumentation. Since the above equipment can break down and give wrong readings.
It is quite difficult to determine this type of failure yourself, so it is better to ask for help from professionals. The problem is solved by replacing the control devices.
Cracks in the heat exchanger in the boiler
Over time, micro-cracks form on the walls of heat exchangers, letting water out of the heating system. Due to the rapid evaporation of water in the boiler, this problem, in contrast to the previous situation, is not easy to detect. Cracks can also occur during maintenance flushing or as a result of a factory defect. This problem can be eliminated by sealing the affected area with a crack.
The water drain cock is not closed tightly
Sometimes the answer to the question: why does the pressure in the gas boiler drops, can be such a simple phenomenon, as not tightly clamped tap. As a result the pressure level in the unit is reduced. Fix the problem quickly and easily by screwing the faucet.
Defective safety valve
The task of the safety valve in the boiler “Navien” is to protect the heating system from excessive pressure. If the values are exceeded, the part opens and begins to discharge excess water. The standard pressure threshold is 2.5 bar.
Wrongly selected safety valve or simple contamination
The wrong valve, leads to a large number of false positives, due to which the pressure will constantly drop. To eliminate this problem it is necessary to replace the valve with a new one.Another point is the accumulation of particles of dirt under the seat. During the use of this element, you can also notice the accumulation of scale and other debris, preventing it from closing freely. You can try to get rid of this debris yourself. Simply twist the valve cap in the desired direction.Then check pressure values for 1-2 hours with a manometer. If the situation has not changed, you need to find another cause of failure.
Leaks in the heating system
A fairly common problem of leaks in the heating circuit. Which explains why the pressure in the gas boiler drops. The rate at which it drops is determined by the extent of the failure. In some cases the pressure is released instantly, in other cases slowly and gradually. If the leak remains in the visible range, it can be identified by water puddles or the appearance of condensation on the surface of the stOuT leaks in pipes and radiators do not require replacing these appliances, since the coolant is able to evaporate when the equipment. Turning on the boiler, pay attention. is there a leak, if so, there will be a puddle under it.
