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What effect does low pressure have on my boiler?

Want to know what happens when boiler pressure is too low? We answer the common questions below.

Is low boiler pressure dangerous?

While a low boiler pressure isn’t dangerous, it can affect the efficiency of your heating system – this means you may end up paying higher heating bills.

Most people do not know that low pressure in a boiler can have a drastic effect on it’s longevity, and many have concerns over whether low boiler pressure is dangerous. A boiler can lose pressure for multiple reasons, it can be due to a leak in the pressure relief valve, an issue in the expansion vessel, air in the system, or a leak in the heating pipework.

If your boiler pressure gauge is showing that your boiler pressure is below the 1 bar mark when running hot water or turning on central heating, it means it’s too low and that it needs to be increased to between 1 and 2. There are many ways your boiler pressure can decrease, but there’s only one tried and tested way to increase it to a normal rate – Call one of our experts today to help increase the pressure of your boiler today- we’ll get it sorted in no time!

Does low boiler pressure affect hot water?

If you find that your hot water isn’t as warm as it should it be, it may be because your low boiler pressure is affecting your hot water temperature. The pressure of your boiler should be around 1.5 bar. If it’s not, use your manual to repressurise your boiler to the recomended number.

If you’re worried about repressurising your boiler yourself, you can always call on the professionals at Greenstar, who’ll have your boiler operating effectively in no time.

For more information about the effects of low pressure on your boiler, contact us today on 01202 355 344


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How to increase your combi boiler’s pressure

If your boiler pressure needs increasing, we recommend consulting a professional. Our team will be more than happy to help you, taking the following steps to get your boiler back in working order in no time.

1. Identify the filling loop and pressure gauge, the filling loop handles should be at a 90-degree angle.
2. Ensure that you can see the pressure gauge whilst accessing the filling loop.
3. Turn off your boiler.
4. Turn both filling loop handles to match the direction of the pipe until you hear water flowing.
5. Once the correct boiler pressure has been reached (1.5), make sure the handles are fully closed – try not to over-pressurise the boiler, keep your eyes on the gauge at all times.
6. Turn the boiler back on to see if your boiler pressure has increased, and achieved a normal scale of 1.5.

If your boiler still has low pressure after following these steps, then we recommended calling our team of experts to quickly fix the issue! We can guarantee a two-hour call out time for all emergency projects, so you can have peace of mind about getting your boiler issue rectified immediately!


Contact our team today on 01202 355 344 for more details about our boiler, drainage, plumbing and heating services throughout Dorset, Hampshire and Wiltshire.

Reference: www.viessmann.co.uk 

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