81-01 High
Your boiler has detected an issue with the sensor that measures the temperature of the water leaving the unit, which usually results in the system shutting down for safety.
Technical description: Flow temperature sensor error – try resetting the boiler
Typical repair cost: £100-180 (including labour)
DIY fix possible
Locate the power button or reset switch on the boiler control panelPress and hold the reset button for five secondsWait for the boiler to restart and check if the error code clears
Protect yourself from future repair bills
A boiler cover plan would cover faults like 81-01 — no call-out fees, no surprises.
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Parts commonly replaced
- Flow temperature NTC sensor
- Wiring harness
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