Water heater trips the electrical breaker or RCD when heating starts.
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: Do not repeatedly reset a breaker that trips immediately. Risk of fire or electric shock. Isolate power and call a qualified electrician if unsure.
- Step 1 – Visual inspection:
- With power off, remove the heater access cover and inspect for signs of water, corrosion, or burnt wiring.
- Step 2 – Dry and secure:
- If moisture is present, identify and fix the source of the leak before re-energizing.
- Step 3 – Insulation test (electrician):
- A qualified person should perform an insulation resistance test on the immersion heater and wiring.
In most cases, a tripping RCD when the heater energizes indicates a failing immersion heater that must be replaced.
Repair Difficulty
Required Part
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