712 Medium
Your boiler has detected a fault with a temperature sensor in part of your heating circuit, which likely means some radiators are not warming up as they should.
Technical description: Return sensor defective (zone 2)
Typical repair cost: £100-180 (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 712 — no call-out fees, no surprises.
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Parts commonly replaced
- NTC Return Temperature Sensor
- Sensor wiring harness
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