Why does the pressure rise in the boiler? What to do to restore work? First of all, to understand the causes of the problem. In this mode, the equipment operates with a double load. In the best case, an error will appear on the display, and the security system will block the operation of the device. In the worst case, if one of the parts breaks, an explosion can occur. How to determine the increase in pressure and lower the pressure, we will describe in this article.
The reasons for the increase in pressure. Ways to solve the problem
It is possible to understand that the system has too much pressure by pressure gauges. Normally, the readings are 1-2.5 Bar. If the 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 exude water.
The case in the expansion tank
This tank can be located separately from the boiler or be part of the structure. Its function is to draw excess water during heating. Hot liquid expands, it becomes 4% more. This surplus is sent to the expansion tank.
If the volume of the product is too small, then it will be completely filled with water. With a subsequent increase in temperature to 85-90 degrees, the tank will no longer be able to compensate for these 4%.Therefore, pressure will increase.
The size of the tank is affected by the boiler output. For gas equipment, its volume is 10% of the total amount of coolant. For solid fuel - 20%.
Rupture of the membrane. If the part is damaged, the coolant is not restrained by anything, therefore it completely fills the compensation tank. Then the pressure begins to fall. If you decide to open the tap to add water to the system, the pressure will rise above normal. A leak will appear in the connections.
A replacement tank or diaphragm is required to reduce pressure.
Head below or above normal. To achieve normal values (ratings) in a gas boiler will help the machine pump.
- Drain all water from the system.
- Turn off the valves.
- Pump the circuit until you are sure that there is no water.
- How to bleed air? Through the nipple on the other side of the supply.
- Download again until the indicators have reached the standards specified in the instructions "Ariston", "Beretta", "Navien" and other brands.
The location of the tank after the pump provokes water hammer. The point is 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 the tank on the return pipe. The next pump crashes in front of the boiler.
Why pressure in closed systems rises
In the double-circuit boiler, air accumulates. Why does this happen:
- Incorrect water filling. The fence is on top, too fast.
- After repairs, excess air was not vented.
- Mayevsky’s taps for air release are broken.
- The impeller of the pump was worn. Adjust or replace part.
To relieve or reduce pressure, fill fluid properly. The fence is carried out from below, slowly, while Mayevsky's cranes are open to vent excess air.
Open system issues
The problems are the same as described above. It is important to properly fill the water and bleed air. If after this the pressure has not returned to normal, it is necessary to drain the system.
Secondary heat exchanger
The unit is used for heating hot water. Its design consists of two insulated tubes. Cold water flows one by one, already heated by another. In case of damage to the walls, the appearance of a fistula, 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:
- Turn off the supply valves.
- Drain the water.
- Open the case, find the radiator.
- The assembly is fastened with two bolts. Unscrew them.
- Remove the defective part.
- Install new gaskets in the mountings and connect the heat exchanger.
Other reasons
There are other reasons for these problems:
- The reinforcement is blocked. When the fence, the pressure rises, protective sensors block the equipment. Inspect the taps and valves, unscrew them until they stop. Make sure the valves are working.
- Filter mesh clogged. It is clogged with garbage, rust, dirt. Remove and clean the part. If you do not want to clean regularly, install a magnetic or rinse filter.
- The feed valve is out of order. Perhaps its gaskets are worn out, then you can do with a replacement. Otherwise, you will have to change the tap.
- Problems with automation. Malfunction of thermostat or controller. The reason is wear, factory defects, incorrect connection. Diagnostics, repair.
Check if the boiler protection details are working: pressure gauge, valve, air vent. Clean radiators and other components from dust, soot, scale. Prevention helps to prevent serious damage to gas equipment.