Heat pumps · Error codes · Cool Energy
E8Cool Energy · EcoStore all-in-one exhaust-air DHW heat pump
E8 on a Cool Energy EcoStore all-in-one exhaust-air DHW heat pump: Electric leakage error
Short answer
On a Cool Energy heat pump, E8 means: Electric leakage error. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Electric leakage error.
Likely causes:
- PCB current induction circuit detects L-N current difference of 14 mA.
- Broken wires or bad wire connection.
Is it safe?
Switch the heat pump off at its isolator and call an engineer.
| Does the heat pump stop? | Partly |
|---|---|
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
What you can check
- Read and note the code shown on the controller display, then contact your installer or service engineer.
- Check the heat pump's breaker/isolator at the consumer unit is switched on (do not repeatedly reset if it trips).
What the engineer will check
- Check supply voltage, phase presence/rotation and balance.
- Check cabling, terminals and MCB/RCBO sizing.
- Check inverter drive/PFC board.
Who to ask for: heat pump electrical.
Certification: Electrical competence (Part P / qualified electrician).
What you might notice
Sources
- Cool Energy EcoStore Heat Pump Water Heater - manual Rev1 ↗ · Rev1 · page 24-26 (printed) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026