Central heating not working but hot water is? Common causes
When the taps run hot but the radiators stay cold, the boiler itself usually works — the problem is in how heat is sent to the heating circuit.
Call 07534 868419 — 24/7Thermostat and programmer
Check the timer is calling for heating and the room thermostat is set above room temperature. Replace thermostat batteries if it's wireless.
Some radiators cold
Cold at the top usually means trapped air — bleed the radiator. Cold at the bottom usually means sludge, which may need a power flush.
No radiators warm at all
On combi boilers a stuck diverter valve is a common cause; on system boilers it can be a motorised valve or pump. These need a heating engineer.
Questions
Do you send a heating engineer or a plumber?
Our Gas Safe Registered engineers handle both heating and plumbing, so one visit covers boiler, radiator and pipework faults.
How much is a power flush?
Power flushing starts from £350 for a system flush, confirmed after we've seen the system.
Local help in your area
- Richmond
- East Sheen
- Barnes
- Putney
- Twickenham
- Teddington
- Wimbledon
- Kingston
- Wandsworth
- Clapham
- Battersea
- Balham
- Tooting
- Fulham
- Chelsea
- Streatham
- Earlsfield
- Southfields
- Kew
More fault guides
- Worcester Bosch boiler not working? What to check first
- Leaking or dripping tap? How to stop it and when to call
- Boiler maintenance checklist: what homeowners should know
- How to clean a shower drain (and when it's more than hair)
- Blocked toilet? What to try before you call a plumber
- No hot water? What to check before you call
Smell gas? Leave the property and call the National Gas Emergency line on 0800 111 999 first.
