F.83 High
Your boiler has detected that the temperature is not rising as expected when the burner is lit, which usually means there is a lack of water or a sensor issue.
Technical description: Flow and or return temperature sensor error
Typical repair cost: £90-180 (including labour)
DIY fix possible
Check the pressure gauge on the front of the boiler is between 1.0 and 1.5 barIf the pressure is low, use the filling loop to top it up to 1.5 barOnce the pressure is correct, press the reset button (indicated by a flame with a cross through it)
Protect yourself from future repair bills
A boiler cover plan would cover faults like F.83 — no call-out fees, no surprises.
*Affiliate links — we may earn a commission at no extra cost to you. Prices shown are starting prices.
Parts commonly replaced
- Flow temperature sensor (NTC)
- Return temperature sensor (NTC)
- Heat exchanger (descaling)
*Affiliate links — we may earn a commission at no extra cost to you.