Low
Viessmann boilers on Viessmann Vitopend 100

Your boiler is currently operating based on internal settings rather than external controls, meaning it may be ignoring your thermostat or running according to the temperature set on the boiler panel itself.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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

Control mode

DIY fix possible

Check that your room thermostat is turned up and has working batteriesEnsure the heating and hot water dials on the boiler front panel are set to your desired temperatureCheck if any external timers or smart controls are disconnected or powered off

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