No hot water but the heating works? Simple checks you can do safely, likely causes and when to call an engineer. Call 020 8050 9933.
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When a combi boiler stops giving hot water, a few quick checks sometimes get it going again. If they do not, the cause is usually inside the boiler and needs a Gas Safe registered engineer.
Make sure the boiler is switched on and has power, the programmer or timer is set to hot water, and the thermostat is not turned right down. Check the gas supply is on and that other gas appliances work. Look for an error code on the display and note it down.
Low pressure can stop a combi boiler producing hot water. Look at the pressure gauge: it should normally be around 1.0 to 1.5 bar when cold. If it is low, our guide to a boiler losing pressure explains how to top it up safely.
In freezing weather the plastic condensate pipe outside can freeze and stop the boiler. Thaw it gently with warm (not boiling) water and reset the boiler. Do not use a blowtorch or boiling water. Insulating the pipe helps prevent it happening again.
If only one tap is cold, the problem is more likely a faulty mixer or blocked fitting than the boiler. If the heating works but the hot water does not, a faulty diverter valve or heat exchanger is a common cause and needs an engineer.
If a reset does not help, an error code returns, or you see leaks, scorch marks or smell gas, stop and call. Never remove the boiler casing yourself. Gas and boiler work must be done by a Gas Safe registered engineer.
Yes. We take emergency bookings 24 hours a day, 7 days a week, and tell you the expected arrival time when you book. A call-out fee applies, shown before you pay.
Boiler repair (labour only) is typically £90 - £150 including VAT, plus the call-out fee. Parts are extra.
Only a Gas Safe registered engineer should carry out gas and boiler work. You can ask to see their Gas Safe ID card.