F37 High
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Technical description: Incorrect system water pressure error – possible sensor damaged or pressure too low
Typical repair cost: £0-160 (including labour)
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath or near the boiler.Slowly open the one or two small valves on the filling loop to allow water into the system.Watch the pressure gauge and close the valves tightly 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 F37 — no call-out fees, no surprises.
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Parts commonly replaced
- Water pressure sensor
- Filling loop
- Expansion vessel
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