0A43 High
Your boiler has stopped working because a internal sensor that monitors the temperature of the water returning to the unit has developed an electrical fault.
Technical description: Return sensor short circuit
Typical repair cost: £90-170 (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 0A43 — no call-out fees, no surprises.
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Parts commonly replaced
- Return NTC thermistor sensor
- Sensor wiring harness
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