Why Is My Boiler Leaking? Causes, What To Do & When To Call an Engineer

A leaking boiler is something you should never ignore. Even a small drip can quickly turn into a bigger issue — causing damage to your home, increasing your energy bills and, in some cases, making your boiler unsafe to use.

If you’ve noticed water pooling around your boiler or dripping from the pipework, here’s what you need to know.

Common Reasons Your Boiler Is Leaking

1. Your boiler is getting old

Over time, seals, internal components and pipework can deteriorate. If your boiler is 10–15 years old, leaks become far more common as parts naturally wear out. An ageing system may also struggle to cope with pressure changes, which leads to more leaks.

2. Corroded pipework or components

Rust and corrosion can eat into metal components inside your boiler. Eventually, small holes form, causing slow and steady leaks. Corrosion might also indicate that the boiler has not been serviced regularly.

3. High boiler pressure

If your boiler pressure is too high, it can force water out through valves and seals. This often shows up as water leaking through the pressure relief valve. High pressure usually happens when:

• The heating system has been recently topped up too much

• The expansion vessel isn’t functioning correctly

• There’s a blockage somewhere in the system

4. Faulty seals or gaskets

Rubber seals inside your boiler can wear down or split, especially in older models. When this happens, water may leak around the pump or internal pipework.

5. Loose or poorly fitted pipework

Boilers and their surrounding pipework are under constant pressure and heat changes. Over time, joints can weaken or become loose, allowing water to escape.

6. Condensate pipe issues (common with modern condensing boilers)

Condensate pipes can become blocked or cracked, especially during colder weather. This can cause water to drip from underneath your boiler.

What Should You Do If Your Boiler Is Leaking?

1. Turn off your boiler

This prevents further damage and reduces safety risks.

2. Don’t try to open the boiler

Your boiler contains electrical components — mixing these with water is dangerous. Never attempt to open the casing unless you are a qualified engineer.

3. Check the boiler pressure

If the pressure is above 2.5 bar, reducing it may temporarily help, but only do this if you feel confident. If not, leave it to a professional.

4. Put a towel or tray underneath

This helps prevent damage to floors or carpets while you wait for an engineer.

5. Call an OFTEC or Gas Safe registered engineer

Leaks rarely resolve themselves. In fact, ignoring a leak can lead to:

• Complete boiler breakdown

• Costly damage to electrics or flooring

• Damp or mould

• Risk of further safety issues

Can You Still Use a Boiler That’s Leaking?

No — you should avoid using a leaking boiler.
Not only can it be unsafe, but it also increases the likelihood of internal damage. Always switch it off and book an engineer as soon as possible.

Why Choose Total Energy Services to Fix Your Leaking Boiler?

If your boiler is leaking, you need a trusted, fully qualified engineer who can diagnose and fix the issue quickly.

Here’s why homeowners across Dorset, Wiltshire, Hampshire and Somerset choose Total Energy Services:

✔ OFTEC & Gas Safe Registered Engineers

Whether it’s an oil or gas boiler, you’re in safe hands with fully accredited experts.

✔ Family-run, local and trusted for over 25 years

We’re a small, independent business based in Blandford, offering honest advice and high-quality workmanship.

✔ Fast response times

We understand how stressful a leaking boiler can be. Our engineers respond quickly and carry common parts to repair your boiler on the same visit where possible.

✔ Which? Trusted Traders

You get reliable, vetted professionals who always put customers first.

✔ Full service area coverage

We fix leaking boilers in:
Blandford, Poole, Dorchester, Weymouth, Shaftesbury, Salisbury, Warminster, Yeovil, Frome, Sherborne, Andover, Ringwood, Bournemouth, Christchurch, Wimborne, Gillingham and surrounding areas.

✔ Transparent pricing

No hidden fees — just honest, clear pricing from a reputable local company.

Need Your Leaking Boiler Fixed Fast?

Don’t wait for a small leak to become a major breakdown.

Call: 01258 472132 and we will do our very best to get an engineer to your home as soon as possible. 

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