Is high boiler pressure dangerous?
The majority of modern boilers often don’t need much more attention than their annual service and the occasional look at the boiler pressure gauge to inform you of the water pressure circulating in the heating system. Keeping your boiler at the right pressure is extremely important as if the pressure is too high, there’s more chance of leaks forming in the system. In this guide, we’ll be answering whether having high boiler pressure is dangerous and how it can be fixed.
What should your boiler pressure be?
Normal boiler pressure should sit somewhere between 1 and 2 bars. The right boiler pressure is typically marked as a range in green on the pressure gauge, with red being the low and high boiler pressure zones. Your boiler might keep working if the pressure is in the red zone but if it’s shutting itself down or won’t turn on, then you’ve got a problem.
Even when your boiler is working as it should be, it’s advised to occasionally check the pressure. As well as this you should know how to release boiler pressure when it’s too high and how to increase the pressure when it’s too low.
Is high pressure in your boiler dangerous?
You will be able to tell when your boiler pressure is too high if:
- The pressure gauge has increased or moved into the red zone
- The system has shut down completely
There are a number of reasons why you may see the boiler pressure increasing to 3 bar or more:
- You might have unintentionally added too much water when trying to fix low boiler pressure.
- The filling valves have been left open accidentally or haven’t been screwed them closed tight enough, which allows water to keep flowing through.
High boiler pressure is not usually dangerous as the heating system is protected by a boiler pressure relief valve (PRV). This valve stops damage from occurring by letting water escape, in some cases through a small pipe via the external wall close to the boiler, when there is too much pressure. Also, a lot of systems are designed to shut down if the pressure becomes too high.
How to reduce boiler pressure when it’s too high
If the problem doesn’t seem too serious, you can try to self-diagnose the problem with your boiler and low the pressure in a few easy steps:
- Turn the boiler off
- Check that the filling loop valves, or the key/keyless filler, are completely and securely closed.
- Wait for the system to cool down, then release pressure by bleeding each of your radiators. Take care as it’s easy to do this wrong, if you’re unsure or make a mistake while bleeding the radiator such as the pin gets stuck or you are unable to get in back in the valve, call a professional immediately.
- Once every radiator has been bled, check the pressure gauge. If it is still too high, you will need to bleed one or more of the radiators again.
- Keep checking until the pressure gauge shows around 1.2 bar or at the very least has gone back to the green zone.
- If the boiler pressure is too low, refer to our other guide that discusses how to increase low boiler pressure, but always make sure that you close the filler valves afterwards.
In the event that your boiler pressure keeps increasing into the red zone, it’s best to call out an engineer. This is because it could be an indication of a problem with the pressure relief valve or a fault within the system. A Gas Safe Engineer will be able to identify and repair the problem, so you’re never left without heating or hot water.
Summary
Even though high boiler pressure isn’t dangerous, it’s still important to get the pressure back to normal as soon as possible. If you need affordable boiler parts to fix a problem with your boiler NBS can help. We offer a wide range of boiler spare parts that will not only help you get your boiler back up and running effectively quickly, but also save you a lot of money on buying parts too. Contact us today if you have any questions or need help finding the right part for your boiler.