How to repressurise your boiler

If your boiler's pressure has dropped too low, you'll need to repressurise it to keep your central heating working efficiently. This simple guide will walk you through the process, which typically takes about 10 minutes.

Step By Step Guide To Repressurise Your Boiler

Before You Begin

First, check your boiler's pressure gauge. The optimal pressure should be between 1 and 1.5 bar when the system is cold. If it's below 1 bar, you'll need to repressurise the system. You'll find the gauge on the front of your boiler, typically displaying either a green zone or specific numbers.

Filling Loop

Your boiler's filling loop is essential for repressurising. It's usually a flexible silver or grey hose with two ends, connecting your boiler to your mains water supply. In some cases, it might be built into the boiler itself. If you can't locate it, consult your boiler's manual.

The Repressurising Process

Start by switching off your boiler and allowing it to cool completely. Once cool, locate the two filling loop valves – they look like taps and are typically at either end of the filling loop. Both should initially be in the closed position (at right angles to the pipe).

Slowly turn both valves to open them (they should be in line with the pipe). You should hear water entering the system. Watch the pressure gauge carefully as it begins to rise. When it reaches between 1 and 1.5 bar, close both valves by turning them back to their original position.

Restart the Boiler

Switch the boiler back on. Some models may require you to press a reset button to clear any error codes triggered by the low pressure. Consult your boiler's manual if you're unsure about this step.

Common Mistakes to Avoid

Take care not to overpressurise the system. If you accidentally exceed 1.5 bar, you can reduce the pressure by bleeding your radiators. Never attempt to repressurise a boiler that's still hot, as this can be dangerous and potentially damage your system.

When to Call a Professional

If you find yourself needing to repressurise your boiler frequently (more than once every few months), this could indicate a leak in your system. Similarly, if you're uncomfortable performing these steps or if your boiler continues to lose pressure after repressurisation, it's best to contact a Gas Safe registered engineer.

By following these simple steps, you can maintain your boiler's pressure and keep your heating system running efficiently. Remember to always prioritise safety and don't hesitate to seek professional help if you're unsure about any aspect of boiler maintenance.

Professional Plumbers in Billingshurst, Pulborough, Storrington and West Sussex

For expert boiler services, get in touch with our highly reliable plumbers by calling us on 07871 725133.