BoilerFaultCodesYour boiler has lost communication with its external thermostat or control unit, meaning it may not know when to turn your heating on or off.
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: Without remote control
What causes this fault?
This fault occurs when the boiler's main control board loses its electronic connection with the external room thermostat or wireless receiver. The most common reason is simply that the thermostat batteries have died or the wireless signal is being blocked by a new physical obstruction. In some cases, it can be caused by a hardware failure within the receiver unit itself or a wiring problem between the components.
DIY fix possible
Check if your wireless thermostat has run out of batteries and replace them if necessary.Ensure the thermostat or remote control unit is within range of the boiler.Restart the boiler using the power button to see if it re-establishes a connection.
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A boiler cover plan would cover faults like A0:0 — no call-out fees, no surprises.
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