Radiator Leaking: What to Do Before the Plumber Arrives

A leaking radiator? Switch off the heating, isolate the radiator and catch the water. Safe steps and when to call. Call 020 8050 9933.

Key facts

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A radiator leak can come from a valve, a joint or a corroded panel. Isolating the radiator and catching the water limits damage until it is repaired or replaced.

Step 1: Turn the heating off

Switch the boiler and heating off and let the radiator cool. Hot water can scald, so do not touch the radiator or the leaking joint until it has cooled.

Step 2: Close the radiator valves

Turn both valves at the bottom of the radiator clockwise to isolate it from the system. Use a cloth for grip, and do not force a stiff valve.

Step 3: Catch and mop up the water

Place a towel and container under the leak. Dry the floor, especially wooden or laminate floors, to limit damage.

Step 4: Find where it is leaking

A drip from a valve nut can sometimes be stopped by a plumber nipping the joint. A leak from the radiator body, often from corrosion, usually means the radiator needs replacing.

Step 5: Check the boiler pressure

A leak lowers system pressure. Check the boiler gauge, and see our guide on a boiler losing pressure. Do not keep topping it up without fixing the leak.

Step 6: Book a repair

A radiator repair is typically £80 - £120 and a single radiator replacement £150 - £250, including VAT, plus the call-out fee.

Quick tips

Related help

Common questions

Can I use the heating while a radiator leaks?

Only after the leaking radiator is isolated with both valves closed. Keep checking for leaks and the boiler pressure.

Do you replace radiators?

Yes. We repair and replace radiators, and carry out central heating work. A call-out fee applies, shown before you pay.

Is a leaking radiator an emergency?

A steady leak, or one near electrics, is. Isolate it and call us. We take bookings 24 hours a day.

Call 020 8050 9933