Heatrae Sadia water heater shows E13 and locks out shortly after start-up.

Safety first: Do not continue to reset and run the heater with an earth leakage fault. Isolate power immediately. Risk of electric shock.

Steps to address E13:

• 1. Inspect for leaks: Check inside the heater for any signs of water leaks onto electrical components. Repair plumbing leaks before proceeding.
• 2. Dry the unit: If moisture is present, dry the area thoroughly and allow time for components to dry before re-energising.
• 3. Check wiring: Look for damaged insulation, crushed cables, or conductors touching the metal casing. Repair or replace damaged wiring.
• 4. Test element insulation (for competent persons): Perform an insulation resistance test on the heating element. Replace the element if readings are below the manufacturer’s minimum.
• 5. Professional testing: If you are not qualified to perform electrical safety tests, contact a registered electrician or service engineer.