Water heater produces no hot water at any tap, display is on but burner does not fire when hot tap is opened
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.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power and close the cold water isolation valve before removing any filters or sensors.
User checks:
- Confirm that cold water pressure at other taps is normal.
- Open a hot tap fully and watch the heater: if there is no ignition attempt (no fan noise, no clicking), the unit is not seeing demand.
Engineer actions:
- Clean the cold inlet filter on the heater.
- Test and, if necessary, replace the DHW flow sensor or microswitch.
- Check the diverter valve for sticking and replace or service if jammed.
Because this involves internal water and gas components, use a qualified technician for diagnosis and repair.
Repair Difficulty
Required Part
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