Stable pressure in the heating system is one of the main criteria for normal operation. If the values are higher or lower than specified, the equipment will not start. Why does water pressure jump in a gas boiler? In the article you will find out the possible causes of the problem. Basic: leak, depressurization, blockage.
We will tell you how to adjust the indicators in order to restore the operation of the device.
System pressure rate
In empty pipes without coolant, the indicators are stable at 1 bar. As soon as you open the stopcocks and the heating medium enters the circuit, the values increase to 3 bar (depending on the model). If the pressure gauge pointer shows less than 0,6 bar or more than 3 bar, the boiler is blocked. Until you eliminate the cause of the jumps, the equipment will not start.
The pressure power is affected by the speed of the circulation pump, the cross-section of pipes, the heating temperature, airiness and the presence of blockages. Each model burning, who are “Bucks” has its own indicators. How much should be the working pressure, indicated in the instructions.
There are different types of pressure:
- Static. The greater the height of the pipes, the higher the value. The rise for each meter is equal to 0,1 bar.
- Dynamic. Forced movement of a liquid by a pump or expansion when the temperature rises.
- Working. Includes the two options above.
- Excess. It is fixed by a measuring device – a manometer.
- Nominal. Depends on the type of construction, materials, production technology.
- Max. Acceptable for normal operation.
- Crimping. High performance during testing in factories.
Why does pressure jump
If you notice a slow decline in performance, check leak heat exchanger. Microcracks appear as a result of poor-quality material, rapid wear. Frequent use of reagents for descaling also leads to sad consequences.
To avoid a problem, install softening filters. They draw magnesium and potassium salts out of the liquid. Finding cracks is difficult. Sometimes they appear as green spots on the surface. In tubular radiators, the hole can be sealed with cold welding or soldering.
Bithermic heat exchangers suffer from water hammer, which causes their tubes to burst. They cannot be repaired, only replaced.
Make-up valve is not sealed. Inspect the part for wear, it should be in the closed position. The valve is used in cases where the pressure in the circuit is reduced, the coolant is not enough and it needs to be pumped up. Replace valve if defective. If you want to permanently leave the valve in the “closed” position, then remove the valve, fill the holes with silicone, connect the valve in the closed position.
Problems with the three-way valve. The element is responsible for the movement of hot water in the system. For example, you have a dual-circuit device installed. When the mixer is opened, the valve switches the flow from heating to DHW and vice versa. If it is broken or clogged, then a lot of liquid will seep into the heating circuit, which will lead to an increase in values. Clean valve or replace.
Manometer blockage. This device measures the pressure in the boiler. If debris gets into its tubes, then it is necessary to clean them. During operation, you must constantly monitor the readings of the pressure gauge.
Leak in the heating system. Use a dry cloth to locate the leak. Inspect the joints, connections, control valves, welding points, make-up for serviceability. Check for water accumulations under the radiators. You may not immediately detect a leak, because moisture quickly evaporates from hot batteries.
In such cases, completely drain the water and connect the compressor to the terminals. During pumping, air will come out through the slots with a certain sound.
Damage must be sealed. You can use sealant, plumbing tow. Before doing this, clean the place of repair.
Expansion tank wear. Inside the tank is divided into two parts by a flexible membrane. One part contains pressurized gas. The other is filled with excess fluid. In the event of a gas leak or a worn/damaged diaphragm, compensation will not occur and the values in the loop will not decrease.
How to pump nitrogen into the tank:
- Turn off the boiler.
- Close the valves from the boiler to the tank (usually it is equipped with two shut-off devices on both sides).
- Drain the water.
- Connect the car pump and pump up the gas.
- Wait for the values to increase.
Does the problem recur after a while? Replace the nipple, membrane, expansion tank.
Air accumulations. The airlock interferes with the normal circulation of the fluid, which means it reduces the pressure. Examine the air vent. If it is overgrown with scale, remove the lid and clean everything. Bleed air from the system through Mayevsky’s taps. To do this, substitute the container and open the valve. Air will come out with the liquid.
Do you hear gurgling sounds when restarting? Repeat the steps until the sounds disappear.
How to start the boiler correctly
To avoid problems with pressure, you must follow the installation and connection rules. What are the steps to go through:
- Compliance with regulations during installation.
- Confirmation of tightness of connections.
- Enable and configure network settings.
- Issuance of a guarantee certificate (if the launch is carried out by a company).
Through the lower eyeliner, the pipes are gradually filled with liquid. When the gauge pointer shows the nominal value, the valve closes. Excess air is removed. If an air vent is installed, the reset is automatic.
Bleed the air from the pump:
- Turn on the unit.
- Remove the cover to expose the pump.
- Loosen the center bolt until water seeps out.
- Then screw it on right away.
It may take a few days for the batteries to warm up. During this time, you will have to bleed the air several times. Monitor the operation of heating equipment, then your house will always be warm.