BoilerFaultCodesYour boiler is simply indicating that it is currently operating to provide heat to your radiators.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: CENTRAL HEATING DEMAND
What causes this fault?
The 'Q' code appears when your thermostat or programmer sends a signal to the boiler asking for heat. It signifies that the internal pump and burner have activated correctly to begin warming the water for your radiators. This is a normal operational message and does not indicate a mechanical failure or a broken part.
This code is most frequently seen during autumn and winter when homeowners turn their heating systems back on after the summer break.
DIY fix possible
Check that your thermostat is set to the desired temperatureEnsure your programmer or timer is set to an 'on' periodWait for the heating cycle to finish, at which point the code will change
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Q — no call-out fees, no surprises.
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