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.

Related FAQs

Where can I find the serial number of my boiler?

Serial number can usually be found on the drop down panel on the front of the boiler. Some boilers have a tag underneath the boiler. Find out more...

Should I turn off my boiler in the summer?

Is it ok to turn off your boiler in summer? The short answer is: it depends on your home and your circumstances. Find out more...

How old is my boiler?

You can find out how old your boiler is by visiting the official industry database. Read more...

How often should I have my boiler serviced?

Boiler repairs can be expensive and inconvenient. We advise you have your boiler serviced every year in accordance with the manufacturer’s instructions.

Why is my boiler pressure low?

The pressure on your boiler can go up or down for different reasons. Find out how to adjust it and what to do if your boiler keeps losing pressure...

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