Why is my boiler losing pressure?

Did you know when the pressure in your central heating system drops too low, it will cause your boiler to shut down automatically? There are many reasons that cause the pressure on your boiler to drop, ranging from leaks to component failures. In this blog, we go through the most common ones.

why is my boiler losing pressure

Reasons why your boiler is losing pressure


One of the most common issues that cause the pressure to drop is leaks in the heating system. The chances of the pipe bursting is low therefore we recommend checking the joints and examining the areas around the radiators where the pipework enters and exits. 

We also recommend looking for clear places on hard floors surrounded by dust, or marks where moisture has persisted for a long time as there could be a slow leak. Although central heating leaks are rarely severe, they do reduce the pressure on your boiler over time.

Not enough inhibitor in the system

An inhibitor is a chemical that is added to the water that flows throughout your central heating system. Doing this helps slow down the chemical reaction between the water and the metal of the radiators and prevents a build-up of gas in the system. 

When water and the metal react, they produced gas, to fix this, you can increase the pressure by simply bleeding your radiators and adding water temporarily.  

Air Vents 

Air vents are integrated into many modern boiler systems to release air build-up before it becomes apparent. You may notice a minor decrease in pressure over time if the air vent is operating properly, and you will simply need to fill your system up with water. However, if the air vent is clogged or jammed, it will cause the air to enter the system, causing the problem to worsen. 

So, although both a functional and a stopped air vent might cause a fall in pressure, the true issue is elsewhere. However, if the vent is clogged or damaged, it must be repaired or replaced by a qualified heating engineer. 

Get in touch with us today

Our team is available to help with any boiler issues you may be experiencing with your boiler, simply call us on 01634 247525 to find out more about our boiler repair services