BoilerFaultCodesYour boiler is working correctly but is currently in a 'waiting' state because your room thermostat is telling it that the house is already warm enough.
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: Room thermostat is blocking heating mode
What causes this fault?
This status code appears when your boiler is ready to provide heat but is being told to stay off by your external room thermostat or timer. It occurs because the temperature in your home has reached the level set on your thermostat, or the programmer is currently in an 'off' period. Once the room temperature drops or your timer kicks in, the boiler will automatically start up again.
This code is frequently seen during the change of seasons when homeowners first turn their heating on but the outdoor temperature is still mild enough to reach the thermostat setting quickly.
DIY fix possible
Check your room thermostat to see if it is set lower than the current room temperature.Turn up your thermostat to a higher temperature to trigger a heat demand.Check if your thermostat batteries need replacing or if the wireless receiver has lost its connection.
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 S.30 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.