WhatsApp call button

Reasons why your boiler is losing pressure

The most common cause of boiler problems is known to be caused by low boiler pressure. Due to leaks and boiler failures, a boiler might lose pressure over time, resulting in no hot water or central heating. As a result, it's vital for householders to understand when a boiler loses pressure and how they can fix it.

low boiler pressure

What is boiler pressure?

Your modern boiler, unlike older boilers, does not require a water storage tank in the loft. Your system will use an expansion vessel in place of the header tank. The expansion vessel absorbs the changes in pressure of water when your heating system warms up the water. This occurs when the temperature and water volume increase and decrease. 

How to check for low boiler pressure

You can check your boiler's pressure by trying to locate the pressure gauge on your boiler, this shows if the pressure is high, appropriate, or inadequate. Many newer boilers are designed to have a screen that displays an error number to identify the source of the issue. Look in your boiler's manual to discover whether your model's fault code matches low boiler pressure. 

Boilers must operate within a certain temperature range in order to function efficiently and safely, this usually ranges between 0.7 bar and 2.5 bar.  If the pressure drops below the prescribed range on occasion, it may normally be refilled using a valve on the system.

causes of low boiler pressure

Reasons for low boiler pressure 


A leak usually happens from radiator valves or other components inside your boiler system. The corrosions and loosening up from the pipes and radiators can cause water to escape and therefore lowering the pressure in your boiler. To check for leaks, simply examine the area surrounding the radiators for any indications of dampness. Because condensation, rather than a leak, might cause the pipes to get wet, be sure you wipe it clean and put a plate underneath it to catch any drips. 

Also, look out for discoloured paint or flaking on pipes, skirting boards and floors or ceilings. The discolouration is one of the symptoms which indicate there is water damage caused by leaks. Our heating engineers highly recommend not trying to fix or repair loose pipework and that you hire a professional and qualified engineer to help fix the issue for you. 

Faulty Component 

Certain boiler components can become defective over time, causing heating issues in the boiler. For example, a damaged pump is less effective and may have difficulty maintaining pressure. As previously mentioned, do not try to locate the malfunctioning boiler component on your own. Instead, contact a Gas Safe registered engineer to look into this and they'll tell you what needs to be fixed or replaced.

High Pump Speed

A pump is required in any pressurised central heating system to move the water around it. However, if the pump's speed is too high, air bubbles could enter the water flow, causing low pressure in your boiler system. The pump can be adjusted to a reasonable speed by a boiler expert.

Want to know more? 

Our heating engineers are based throughout Redditch, Studley, Alvechurch and Bromsgrove. Speak with a member of the team today by calling us on 07976 271 681 and we will be happy to answer any questions you have regarding your boiler. 

We hope you choose Lakins Heating & Plumbing for any boiler repair services that you may require.