Home Boiler repair Cardiff
Boiler repair in Cardiff
Tell us what the boiler is doing and we pass the job to Gas Safe registered engineers who cover your Cardiff postcode.
Nearly four in five Cardiff homes rely on a mains gas boiler and nothing else, so when it fails the whole house goes cold. Most faults are fixed in one visit once the engineer knows which part to bring, so a clear description and the fault code on the display save time.
Cardiff at a glance
- Water hardness
- Moderately hard. Welsh Water's postcode checker places the Cardiff Bay / Canton / Cathays, Heath & Llanishen and Ely / Radyr / Llandaff supply zones, and Penarth / Barry, in its moderately hard band. Much of west Wales, including Swansea, is soft. Source
- Renting
- 24.3% of Cardiff households rented privately in 2021 and 17.2% rented from the council or a housing association. Source
Smell gas? Do this first
Turn off the gas at the meter if you can, open the windows, don't use switches or naked flames, and call the National Gas Emergency Service on 0800 111 999. A repair engineer comes after the emergency service has made the supply safe.
Worth checking before anyone visits
Look at the pressure gauge. Below 1 bar, many boilers lock out, and topping up through the filling loop may get you going again. Our boiler pressure guide shows how.
In a cold snap, a frozen condensate pipe is a common cause of lockouts in Cardiff semis, where the pipe often runs down an outside wall. Pouring warm, not boiling, water along it and resetting the boiler can clear it.
Faults that build up over years
Cardiff's moderately hard supply leaves scale on the plate heat exchanger of a combi. The first sign is usually hot water that runs hot then cold, or a boiler that cuts out when a tap is half open. A diverter valve that sticks gives you heating but no hot water, or the reverse.
Older systems also collect black sludge from corroding radiators. If the engineer finds the pump or heat exchanger struggling, ask whether a magnetic filter or a system flush should be part of the fix.
Renting? Repairs are the landlord's job
In Wales, your landlord must keep the heating and hot water in repair. Report the fault in writing to the landlord or agent and keep a copy. If you are without heat and they don't respond, Cardiff Council can step in on privately rented homes.
Cardiff homes and what they need
Victorian bay-fronted terraces
Long pipe runs to a back kitchen boiler mean older terraces lose pressure from small leaks under floorboards. If you top up more than once a month, ask the engineer to trace the leak rather than just reset the boiler.
Interwar and post-war semis in the northern suburbs
Regular boilers here have more parts to fail: the motorised valve, the programmer and the cylinder stat. Tell the engineer whether you have no heating, no hot water or neither, as that narrows it down.
Modern apartments around Cardiff Bay and the centre
Flat boilers often flue through a long horizontal duct. If the fault code points to the flue or fan, the engineer may need access to a ceiling hatch, so check with the managing agent first.
Areas covered
Engineers who cover Cardiff work across areas including Roath, Cathays, Canton, Pontcanna, Grangetown, Splott, Llandaff, Whitchurch, Rhiwbina and Penarth.
Questions people in Cardiff ask
Is it worth repairing a boiler over ten years old?
Often, if the part is easy to source. If the heat exchanger has failed or parts are no longer made, compare the repair price with our new boiler cost guide before agreeing.
Do I need a Gas Safe engineer for every repair?
Yes, for anything involving the gas side of the boiler. Check the engineer's card on the Gas Safe Register before they start.
Sources
Also nearby: Boiler repair in Swansea, Boiler repair in Bristol, Boiler repair in Gloucester