BoilerFaultCodesYour boiler has lost the ability to monitor the temperature in your second heating zone because a sensor has developed an electrical fault.
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: Heating circuit M2 room temperature sensor shorted out
What causes this fault?
This fault occurs when the electrical signal from the secondary heating zone's temperature sensor is interrupted by a short circuit. The most common reason is that the delicate internal wiring of the sensor has degraded or has been physically pinched, causing the sensor to send an incorrect electrical reading back to the main control board.
This fault is often noticed at the start of autumn when homeowners first try to turn on their secondary heating zones after the summer break.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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