BoilerFaultCodes.com
S.34 Medium

Your boiler has paused because it detects a risk of its internal pipes freezing while trying to heat your home.

Technical description: Heating mode frost protection error
Typical repair cost: £0-120 (including labour)

DIY fix possible

Check that the room thermostat is turned up to call for heatEnsure any radiator valves in the room with the thermostat are fully openWait 15-30 minutes for the boiler to automatically clear the status once it detects a safe temperature riseGently increase the property temperature to thaw the surrounding air

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