BoilerFaultCodesWhat the manual says
Manufacturer manualCommunication to the thermostat interrupted
What causes this fault?
This fault occurs when the wireless link between your boiler and your wall thermostat is broken, preventing the boiler from receiving instructions to turn on. The most common reasons are dead batteries in the thermostat unit or an obstruction like a new piece of metal furniture blocking the radio signal between the devices.
This issue often appears at the start of autumn when homeowners try to turn their heating on for the first time in months, only to find the thermostat batteries have drained over the summer.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Avoid the next call-out bill
A cover plan would handle faults like A8: no call-out fees, no surprise bills.
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