Ravenheat DHW Priority / Flow Detection Fault

Furnace fails to respond to hot water demand (for Ravenheat combi-style furnace/boiler), but heating works.

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

Faulty DHW flow switch or turbine, Stuck diverter valve, Blocked DHW heat exchanger, Wiring fault to DHW sensors

How to Fix / Troubleshooting

Safety: Hot water circuits can become very hot; isolate power and water before disassembly.

User checks:

  • Run a hot tap fully open and observe if the furnace attempts to fire.
  • Check that cold water supply to the appliance is on.

Technician checks:

  • Test DHW flow switch/turbine for correct operation.
  • Inspect and exercise the diverter valve; replace if seized.
  • Descale the DHW heat exchanger if restricted.
Advertisements

Repair Difficulty

Hard 4/5

Required Part

Diverter Valve
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements