F.22 High
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Technical description: Safety switch-off – low water pressure in boiler
Typical repair cost: £0-120 (including labour)
DIY fix possible
Locate the filling loop (a flexible silver hose) underneath or near the boiler.Slowly open the one or two taps on the hose until you hear water flowing.Watch the pressure gauge and close the taps once the needle reaches between 1.0 and 1.5 bar.
Protect yourself from future repair bills
A boiler cover plan would cover faults like F.22 — no call-out fees, no surprises.
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Parts commonly replaced
- Filling loop valve
- Pressure sensor
- Expansion vessel
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