Boiler Pressure too High

In News by Thea Vermeulen

The pressure gauge on your boiler needs to be just right for it to run efficiently and safely. If you notice that boiler pressure is too high, this can indicate potential issues with your boiler and/or system.

Common Causes of High Boiler Pressure:

1. Boiler Needs Replacing

Your boiler, as with everything has a “lifespan”,  there will come a time when your boiler is no longer economical to repair or indeed can no longer be repaired due to age or failure and availability of components.    

If after doing the sums it may be a consideration to replace the boiler and/ or radiators and pipework depending on efficiency of your existing system. It is possible to get financial support when you need to replace your boiler, however, make sure to go through a credit broker that is authorised and regulated by the Financial Conduct Authority in England.

2. Standard Faults

The expansion vessel, pressure release valve and the filling loop are some of the common causes of too much water or air pressure in your boiler.

You could check the filling loop and attached isolation of valves yourself  but advise that any fault is boilers need to beattended to by a Gas Safe Registered engineer to ensure that your family and your home are safeand you have heating.

Please make sure to call a Gas Safe Registered engineer as soon as you notice any problems with your boiler, they will assess and provide advice on any required further action to get the best resolution.

3. How to Fix High Pressure Boilers

You might find that you can solve the issues with water pressure yourself if they are not too complicated. For example, a filling loop valve may have been left slightly in the open position which would result in the system over pressurising, this would show as a high reading on the pressure gauge.

A “high” pressure could be considered as the gauge reading in excess of 2bar

** This check must be done when the system is switched off and cold** than 1.5 bars, then the pressure is too high.

It is recommended that a Gas Safe Registered engineer attends to assess the system pressure and adjust before running the boiler to check for the cause of the rising pressure. Our engineers carry a stock of parts if needed and can advise you on any repairs if required.

You could try bleeding the radiators to release pressure, you should only open the radiator bleed valves a little bit, be careful not to take the bleed nipple out fully, a panic may ensue if the nipple is dropped and possibly lost.

Let the water bleed until the excess water has come out of your boiler, which you can track using the pressure gauge.

For this, you should have a towel or receptor to catch the waterand protect floor coverings when bleeding radiators around the house.


Don’t hesitate to get in touch with us today. Our team of experienced, skilled and qualified engineers can cater for all your gas heating, central heating and domestic plumbing needs.