What is the nominal pressure in the boiler? This is the indicator declared by the manufacturer at which the equipment works properly. It is important to know and monitor changes in values during equipment operation. Strong jumps can lead to equipment failure and an emergency.
We will figure out how to properly control and maintain the boiler.
What should be the normal pressure in the gas boiler
The value may differ for each make and model of equipment. The exact figures can be found in the passport data. The average gas pressure depends on the design of the boiler:
By type of installation | Nominal value (mbar) | Minimum (mbar) |
Wall mounted | 13,0 | 4,5 |
Floor | 18,0 | Depends on the type of automation and settings |
With atmospheric burners | 15,0 | 5,0 |
The “minimum” column indicates the indicator below which the boiler will not work. In this case, the protective automation will turn it off in order to avoid a serious breakdown or accident.
In the European-style gas supply system, the nominal value is 20 mbar, while in our regions it is 12–18 mbar. Consumption depends on the type of fuel consumed: liquefied or main.
Appliance brand | min Pa liquefied gas (mbar) | Max. Pa liquefied fuel | min Pa natural gas (mbar) | Max. Pa natural gas |
Wisman | 5 | 23 | 25 | 31 |
DEU | 4 | 25 | 28 | 33 |
Buderus | 4 | 22 | 27 | 28 |
Ferolly | 5 | 35 | 2,2 | 17,5 |
Proterm | — | — | 13 | 13 |
In addition, there are other types of pressure - water and atmospheric. Water is indicated by the unit of measurement Pa. Until the moment of filling with water, the atmospheric indicator is maintained at 1 Bar.
Values in the expansion tank and heating system
The expansion tank serves for the selection of excess fluid. During heating, the liquid expands, which leads to an increase in values (norm 1.5 Bar). To avoid damage, the excess is taken into the tank, and after cooling it is returned to the system.
A pressure gauge is installed to measure pressure. With changes, the pressure gauge needle indicates the minimum or maximum permissible value. To change the situation, air is injected with a nipple.
To install the tank correctly, proceed as follows:
- Find out the rating for your model. The setting in the expansion tank must be 0.3 Atm lower than in the heating circuit.
- Set these values before connecting the tank.
- After connecting, fill the circuit with liquid. Watch for changes on the pressure gauge. Once they have reached the norm, turn off the water supply.
- Start the pump.
- Set the highest temperature on the thermostat. This is done so that the fluid expands as much as possible and fills the expansion tank.
The higher the speed of the circulation pump, the faster the coolant moves through the system. Consequently, the pressure force is greater. There are no specific indicators of the nominal pressure in the circuit.It is believed that the difference in the pressure force in the inlet and return pipes should not exceed 0.3–0.5 Atm.
How to measure readings in a dual-circuit boiler? A pressure gauge is also used for this.
Brand | Operating pressure in the heating system (Bar) |
Arderia | 1–2 |
Navien Ase | Until 3 |
Ariston 24 | Until 3 |
Immergaz 24 | Up to 2 |
Cooper 09-K | Up to 2 |
"Baksi" wall | Until 3 |
Beretta | Up to 4 |
Why does the pressure drop? Reasons for the plumbing system:
- Leaking in pipe connections, heat exchanger. To fix the problem, inspection, sealing and replacement of faulty components will help.
- Malfunctions of the three-way valve. Clean it from clogging.
- Deterioration of a membrane of a broad tank. In case of deformation and damage, a replacement is carried out.
Reasons for the gas main:
- A sharp increase in the load on the highway. This occurs in severe colds. It remains to wait for the restoration of the feed.
- Clogged filter, hose, nozzles. Cleaning in progress.
- Gas valve malfunction. Perhaps the mechanism is jammed or valve replacement is required.
- Leak in the pipes. If you smell gas, shut off the supply valve and call the emergency service.
Monitor the operation of the boiler and its performance. Then it will be possible to avoid breakdowns and accidents.