What causes a drop in boiler pressure is a question we get asked quite often and thankfully it is usually a simple problem to fix.

If the pressure in your boiler drops below 1 bar, then it can cause the boiler to shut down leaving you with no hot water or heating.

So, what causes the pressure to drop in a boiler? There are two main reasons.

• Leaks: A leak anywhere in your boiler system can cause a drop in pressure. Even if the leak is tiny, over time it can cause the pressure to drop. Whilst you can look for leaks around radiators or the boiler itself, you should never look inside your boiler. If you have a continuous flow of water running through your pressure relief valve, then debris may have become lodged inside. This is one of the most common problems but would require a Gas Safe engineer to do the work. The valve may need to be cleaned or replaced which is normally inexpensive to do.
• A leak in your central heating system: This can cause your boiler to lose pressure too. Check for signs of a leak such as a damp floor, leaky pipes or stains on the ceilings. If you can find the leak before an engineer comes out it could save them time and you money.
• Radiators: If you have recently bled your radiators, you may find your pressure level has dropped as air has been released.