What should my boiler pressure be set at?

The normal operating water pressure for your boiler and central heating system is between 1.0 and 2.0 bar.


If the pressure drops below 1.0 bar, you need to repressurise it. On the pressure gauge on the front of your boiler, the needle will be in the centre of the green triangle on the dial.

When your boiler is heating up your hot water or radiators, the needle will go up a little, but should not go higher than about 2.5 bar. The needle should stay in the green section. If it is too high, a safety valve is fitted that will discharge water to keep the pressure at a safe level. You may need to bleed your radiators to reduce the pressure in the system.

How to repressurise your boiler

It is quite simple to top up the water pressure in your boiler. You should be able to do it yourself without having to call a heating engineer.