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Boiler Leaking Water? What to Do Now (and What It Usually Means) | ARA Services

Boiler Leaking Water?
What to do now (and what it usually means)

This is the “get it under control” page. If you’ve spotted water under the boiler or dripping inside the cupboard, your job is to keep people safe, protect electrics, and stop a small leak turning into a soaked floor. Then we’ll sort the repair properly.

If you’re here because you searched “boiler repair near me” or “emergency boiler repair” and you’re watching it drip… start with the first box below.

Book boiler repairs Call a Gas Safe engineer Make it safe first

If the boiler is leaking and also cutting out with a fault code, don’t keep resetting it — use this lockout guide and then call.

If water is near electrics, treat it as urgent. If water is dripping onto wiring, sockets, the boiler’s electrical connections, or you can see sparking/burning smell: stop and use the emergency checklist, then route to emergency boiler help. If you’re unsure, call +44 7727 154746 and we’ll talk you through it calmly.

What to do right now (safe, simple, no heroics)

Quick, lived-in detail: when a boiler leak happens, people often do the opposite of what helps — they keep the boiler running “because we need hot water”, and they wedge a towel under it and hope. The towel bit is fine. The “keep it running” bit is how cupboards get wrecked.

1) Keep electrics dry

If the leak is anywhere near electrical parts, do not touch wet switches or cables. If it’s safe and dry to do so, turn off the boiler using the fused spur switch.

If you can’t do it safely without touching anything wet, leave it and call. Safety first.

2) Contain the water (bucket + towels)

Put a bowl/bucket under the drip, and protect the floor with towels. If it’s inside a kitchen unit, crack the door open so it can dry a bit rather than steaming itself.

Take a quick photo of where it’s coming from — it helps diagnosis massively.

3) If it’s a big leak, isolate the boiler’s water feed (only if you know what you’re doing)

Many boilers have isolation valves on the flow/return underneath. If you know them and they’re accessible and dry, you can turn them a quarter-turn to close.

If you’re unsure, don’t start turning random valves. It’s easy to make it worse.

4) Don’t keep topping pressure up

When there’s a leak, topping up pressure can turn a drip into a steady run. If you’ve been refilling daily, pause and read: boiler losing pressure causes.

This page is “contain + make safe”. The deep pressure diagnosis lives on the pressure page.

5) If you smell gas or feel unwell, stop and treat it as an emergency

A water leak isn’t the same as a gas leak — but sometimes faults overlap. If anything feels off, use the safety decision tree.

If you have a CO alarm, always take it seriously.

What the leak “type” can hint at (quick, not overly technical)

You don’t need to diagnose it, but recognising the pattern helps you describe it on the phone.

Drip from a copper pipe outside (or near the wall by the flue)

Often a PRV discharge. That can be caused by pressure spikes (expansion vessel issues) or a PRV that’s not resealing.

If pressure has been swinging high when hot then dropping low later, that’s a clue: pressure drop patterns.

Water directly under the boiler casing

Could be internal components (pump seals, heat exchanger joints, diverter valve, internal pipework). This usually needs a proper inspection and parts if required.

If water is inside the casing area, keep it off and book a repair.

Slow dampness / staining around pipe joints or radiator valves

Often a system leak rather than the boiler itself. It still causes low pressure and lockouts. If the heating also keeps cutting out, read: why boilers lock out.

Those tiny “weeps” add up over weeks.

Water that looks like clear “condensation” near a plastic waste pipe

Could be condensate-related rather than a pressurised leak (still needs sorting, but different urgency). If it’s freezing weather and the boiler won’t run, the triage steps are here: no heat / no hot water checks.

Don’t confuse condensate drips with pressurised leaks — describe what you see and we’ll guide you.
Contain water Protect electrics Don’t keep refilling Book Gas Safe repair

If you’re researching pricing before booking, use: boiler repair cost in London. This page stays focused on what to do right now.

Let’s get the leak stopped properly.

We’ll find the source, make it safe, and repair it the right way. If you’re looking for local boiler repair, boiler repairs, or a trusted boiler repair near me option in London, book here.

Scenario CTA: if you’ve got water dripping inside a kitchen cupboard and you’re worried it’s going to hit electrics, call +44 7727 154746 and tell us where the drip is and whether the boiler display is still on.

Boiler leaking FAQs

Should I turn the boiler off if it’s leaking?

If you can do it safely without touching anything wet, yes — turn it off at the fused spur and keep electrics dry. If water is near electrics or you’re unsure, treat it as urgent and call.

Can I keep using the boiler if the leak is small?

It’s risky. A “small” leak often gets worse under heat/pressure cycles, and it can damage electrics or the casing area. Contain it and arrange a repair.

Why does a leak sometimes come with low pressure?

Because the system is losing water. If you’re topping up frequently, that’s a sign to diagnose the cause: boiler losing pressure.

When is a leaking boiler an emergency?

If water is affecting electrics, the leak is heavy/fast, or you suspect a safety issue, use: is this a boiler emergency? and route to emergency boiler help.

How much does it cost to fix a leaking boiler?

Depends on the source (valve/seal vs internal component). Typical ranges are here: boiler repair cost in London.