Is your boiler pressure too high? If your boiler is still working, you probably shouldn’t worry yourself too much – there likely isn’t anything wrong with the appliance at all, and you may be able to get the boiler water pressure down to recommended levels without breaking a sweat.
Why is my boiler pressure high?
We often say that a boiler’s pressure should be at around one bar, but this is only when your central heating is turned off and you are not running any hot water. When your boiler starts heating up water, the water expands (think of how steam takes up more space than water), which causes the pressure gauge to jump up.
Boilers are well-prepared to handle these rapid jumps in pressure, as they have an in-built pressure relief valve. Therefore, you don’t need to worry even if the pressure gauge needle is pointing at the red area or looks far beyond safe limits if you are currently using your central heating and hot water. When you turn the heating and water off, the boiler pressure gauge should fall back to safe levels within a few minutes.
How to bring down your boiler pressure
- If you have recently repressurised your boiler, then you may have inadvertently left the valve or filling loop you turned to pump water into the boiler open. Even if you haven’t recently raised your boiler’s pressure, you may have accidentally knocked this valve or it may have become loose. Check that this valve is tightly closed.
- Bleed your radiators. This reduces the pressure in your central heating system and therefore reduces the pressure in your boiler. Continue bleeding the radiator after you have expelled all the air from it until the pressure gauge returns to safe levels.
If you can’t get your boiler pressure down, then you may need to repressurise your expansion vessel, or there may be a fault with the filling loop.
You will need to get a registered engineer to do this for you. However, as boilers contain pressure relief valves, you don’t have to concern yourself too much – if the boiler is not making any noises and seems to be working properly, then it will be safe for the time-being, and the pressure relief valve will prevent the boiler from overpressurising.
Still having trouble?
Don’t attempt to touch any part of your boiler or central heating system if you’re unsure. Did you know? It’s illegal for anyone to use a gas appliance if they think it’s unsafe. It’s always better to be safe than sorry as you could make things worse.
Instead, call us on 0345 3192 247 and we can help. Our technical team will run through some simple troubleshooting to see if your problem can be resolved on the phone or they can book one of our friendly and knowledgeable Gas Safe Registered engineers to get you back up and running as soon as possible.
If your boiler pressure is too low or your boiler is losing pressure, be sure to read our guide on low boiler pressure.
247 Home Rescue accepts no liability for any injuries or damages you sustain following the advice on this website. If in doubt, seek professional assistance.