E31 High
Your boiler has lost communication with the internal sensor that monitors the temperature of the water leaving the unit, usually due to a loose wire or a faulty part.
Technical description: Flow sensor open circuit – check connections to flow sensor are in place
Typical repair cost: £90-180 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Protect yourself from future repair bills
A boiler cover plan would cover faults like E31 — no call-out fees, no surprises.
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Parts commonly replaced
- Flow Thermistor
- Wiring Harness
- Main PCB
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