No hot water after a power cut
✅Free DIY guide — no sign-up required. Written by a qualified Gas Safe engineer.
DIY Friendly💷 £0–£0⏱ 5–10 min
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Most likely cause & what to check
1
After a power cut, most modern boilers go into lockout and need manually resetting.
2
Locate the reset button on your boiler and press and hold for 3–5 seconds.
3
Check your programmer — these often reset to factory defaults after a power cut.
4
Check boiler pressure — repressurise to 1–1.5 bar if below 1 bar.
5
If the boiler still won't fire, a power surge may have damaged the PCB — a Gas Safe engineer should inspect it.
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