BoilerFaultCodes.com
D3 232 High

A safety switch or an external control, such as a thermostat or a condensate pump, has tripped and told the boiler to stop running.

Technical description: The external switching contact has opened
Typical repair cost: £90-220 (including labour)

DIY fix possible

Check if your thermostat or programmer is calling for heat and has working batteries.If you have a condensate pump, check if it is full of water or blocked.Ensure all external switches or emergency stop buttons near the boiler are in the 'On' position.

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