75 / 76 High
Your boiler's internal thermometers are misreading the temperature or have failed, which has caused the system to shut down for safety.
Technical description: Return/flow sensor fault from possible failure of one or both sensors
Typical repair cost: £120-210 (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 75 / 76 — no call-out fees, no surprises.
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Parts commonly replaced
- Flow NTC sensor
- Return NTC sensor
- Wiring harness
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