Boiler breakdowns peak on the first cold weeks of the year, when systems that have sat idle all summer are suddenly asked to work hard. These checks help you avoid becoming one of them.
1. Fire it up early
Turn the heating on for an hour in early autumn. It's much easier to get a fault fixed in September than in a cold snap.
2. Check the pressure
Most combi boilers should read around 1–1.5 bar when cold. If it's low, top up using the filling loop following the manual. If it keeps dropping, there's a leak or faulty component — call an engineer.
3. Bleed your radiators
If radiators are cold at the top, bleed them with a radiator key, then re-check the boiler pressure.
4. Look for cold spots at the bottom
Cold at the bottom usually means sludge. A power flush can restore full heat.
5. Book the annual service
An annual boiler service catches worn parts early and keeps manufacturer warranties valid.
6. Protect the condensate pipe
The plastic pipe running outside from your condensing boiler can freeze, locking the boiler out. Lagging it helps. If it freezes, pouring warm (not boiling) water along it usually thaws it.
7. Lag pipes in lofts and outbuildings
Exposed pipes in lofts, garages and under floors are most at risk of freezing and bursting.
8. Test your CO alarm
Press the test button and replace batteries or the unit if it's expired.
If anything doesn't look right, our heating engineers can help — book now before the winter rush.
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