BoilerFaultCodesYour boiler is working correctly but currently has no request from your thermostat or taps to provide heating or hot water.
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: Boiler in standby – no heat energy demand
What causes this fault?
This code is simply a status message indicating your boiler is waiting for a command to start. It occurs when your home has reached the desired temperature on your thermostat and no hot water taps are currently running. The boiler remains powered on and ready to react the moment it detects a drop in room temperature or a request for hot water.
This code is more visible during the summer months when the heating is switched off, as the boiler spends the vast majority of its time in this standby state.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperatureEnsure your heating programmer or timer is set to 'On'Check if the batteries in your wireless thermostat need replacing
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A boiler cover plan would cover faults like 203 0 — no call-out fees, no surprises.
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