BoilerFaultCodes 412 Medium Warning
Your boiler has lost communication with the temperature sensor that controls the second heating zone in your home.
Book a service
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Room sensor circuit open or short circuit zone 2
What causes this fault?
This fault occurs when the boiler's control board can no longer read temperature data from the thermostat or sensor dedicated to the second heating area of your home. The most common reason is a loose electrical connection, a broken wire, or a failure within the sensor itself that prevents it from sending a signal.
Typical repair cost £90-180 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 412 — no call-out fees, no surprises.
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