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

Should I turn off my boiler in the summer?

Generally, it is best to keep your boiler switched on even during the summer months, however this can depend on your home and your circumstances.

Is a condensing boiler a combi boiler? 

Is a condensing boiler the same as a combi boiler? The short answer is yes. However, there are 3 types of condensing boilers.

Why should I get the water in my central heating system cleaned?

If your boiler breaks down due to sludge in the system, the repair work is not covered under your warranty and can lead to expensive repair bills as a result.

Why should I have a filter fitted?

Many boiler breakdowns occur due to sludge in the heating system. A magnetic filter is an effective way of preventing this sludge from accumulating, and may prevent costly breakdowns at a later stage.

How often should I have my boiler serviced?

We advise you have your boiler serviced every year in accordance with the manufacturer’s instructions and to keep your warranty valid.

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