Why Is My Boiler Losing Pressure? Common Causes and What You Can Do

If you’ve noticed that your boiler pressure keeps dropping, you’re not alone. It’s one of the most common reasons homeowners search for a Gas Safe engineer or plumber. While topping up the pressure can sometimes solve the problem temporarily, repeated pressure loss usually means there’s an underlying fault that needs attention.

At DV Plumbing and Gas Services, we provide professional plumbing and heating repairs, boiler servicing, boiler repairs and general maintenance to help keep your home warm, safe and energy efficient.

What Is Boiler Pressure?

Most modern combi and system boilers work best when the pressure gauge sits between 1 and 1.5 bar when the system is cold. If the pressure drops too low, your boiler may stop working properly or display a fault code.

Common Reasons Your Boiler Is Losing Pressure

1. A Leak in Your Heating System

Even a small leak from a radiator valve, pipework or an underfloor heating system can cause your boiler pressure to fall over time. Small leaks often go unnoticed until the pressure keeps dropping.

2. A Faulty Pressure Relief Valve

The pressure relief valve is a safety device designed to release excess pressure. If it becomes worn or damaged, it may allow water to escape even when it shouldn’t.

3. Bleeding Radiators

If you’ve recently bled your radiators to remove trapped air, it’s normal for the pressure to drop slightly afterwards. The system simply needs repressurising.

4. Expansion Vessel Problems

The expansion vessel helps regulate pressure inside your central heating system. If it loses its air charge or fails, your boiler may repeatedly lose pressure and require professional repair.

Can I Repressurise My Boiler Myself?

Many boilers can be safely repressurised using the filling loop, following the manufacturer’s instructions. However, if the pressure continues to fall after topping it up, it’s important to have the system checked by a qualified engineer rather than repeatedly adding water.

How DV Plumbing and Gas Services Can Help

Our experienced engineers diagnose boiler faults quickly and provide reliable repairs to get your heating back up and running.

We offer:

• Boiler repairs

• Boiler servicing

• Central heating repairs

• Radiator repairs

• Leak detection

• Plumbing repairs

• Gas appliance servicing

• Emergency plumbing call-outs

• Landlord gas safety certificates

• General plumbing maintenance

Whether you have no heating, no hot water, a leaking pipe or a boiler fault, we’re here to help.

Why Regular Boiler Servicing Matters

An annual boiler service helps identify small problems before they become expensive breakdowns. Regular servicing can improve efficiency, reduce energy bills, extend the life of your boiler and ensure it continues to operate safely.

Looking for a Reliable Local Plumber or Gas Engineer?

If you’re looking for an experienced, friendly and reliable plumbing and heating company, DV Plumbing and Gas Services is here to help. We take pride in providing honest advice, quality workmanship and excellent customer service.

Whether you need a boiler repair, annual service, plumbing repair or central heating maintenance, contact DV Plumbing and Gas Services today to arrange a visit.