Medium
6-t5 on Worcester Bosch Greenstar 2000

Your boiler is stuck in hot water mode, meaning your taps will work but your radiators will fail to heat up.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

3-way valve permanently in the DHW heating position: 0: heating, 1: DHW.

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Turn the boiler power off at the fused spur switch for 30 seconds and turn it back on to reset the valve position.Press the 'Reset' button on the boiler control panel.Ensure your room thermostat is calling for heat to encourage the valve to switch.

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