Worcester Bosch
Central Heating Flow Fault / Diverter Valve Stuck on Hot Water
Boiler runs but radiators do not get hot, hot water works normally.
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Stuck diverter valve, Faulty diverter valve motor, Blocked central heating filter, Room thermostat or control not calling for heat
How to Fix / Troubleshooting
Safety first: Allow system to cool before touching pipework.
- Check controls: Ensure the room thermostat is turned up and the programmer is set to heating ON. Check any wireless thermostat has good batteries and signal.
- Feel the pipes: With heating demand on, feel the flow and return pipes under the boiler. If the DHW pipe is hot but CH flow is cold, the diverter valve may be stuck.
- Check system filter: If fitted, clean the system filter following the manufacturer's instructions.
- Engineer tasks: An engineer should test the diverter valve motor, free or replace the diverter valve assembly, and flush the system if sludge is present.
Advertisements
Repair Difficulty
Hard
4/5
Required Part
Diverter Valve Assembly
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements