Termet
No Central Heating / Diverter Valve Stuck in DHW Position
Boiler runs for central heating but radiators remain cold while 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 three-way diverter valve in Termet hydraulic block, Faulty diverter motor or microswitch, Control signal from PCB not switching to CH, Blocked CH filter or valves closed
How to Fix / Troubleshooting
User checks:
- Ensure the room thermostat or programmer is calling for heat.
- Check that radiator valves and any system valves are open.
- Observe the boiler display to confirm CH demand is recognised.
Technician checks:
- Inspect and test the three-way diverter valve for movement when switching between CH and DHW.
- Replace the diverter valve cartridge or motor if stuck.
- Check for blockages in the CH circuit and clean any system filters.
- Verify PCB outputs for CH mode.
After repair, confirm that both CH and DHW operate correctly.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
Three-Way Diverter Valve
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements