BoilerFaultCodesYour boiler is not firing up because the thermostat is turned too low or is currently switched off.
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: Main burner fails to light, pilot burning. Boiler thermostat set to ‘OFF’ or low setting.
What causes this fault?
This issue occurs because the boiler's internal temperature control is set below the level required to activate the main burner. While the small pilot light remains lit, the boiler effectively thinks it has already reached the desired temperature or has been told to stay off. Adjusting the control knob to a higher number completes the electrical circuit needed to call for heat.
This is frequently seen during the first cold spell of autumn when homeowners forget the boiler thermostat was turned down or off during the summer months.
DIY fix possible
Check the boiler thermostat dial on the front of the unit.Turn the thermostat dial clockwise to a higher setting.Ensure any external room thermostats or programmers are also set to 'ON' and turned up.
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A boiler cover plan would cover faults like C.(1) — no call-out fees, no surprises.
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