Control panel displays E04 and spa cannot heat

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

Failed heater element, Burned heater relay contacts, Loose heater wiring, Damaged main PCB

Safety first: Unplug the spa and do not attempt to bypass any heater safety devices.

1. Basic reset:
- Unplug for 10–15 minutes, then reconnect and test heating.
2. Check for tripped breakers:
- Ensure the household breaker has not tripped.
3. Listen for relay click:
- When enabling heat, listen at the heater pump unit for a click. No click may indicate relay/PCB failure.
Do not open live circuits: Internal heater and PCB testing should be done only by qualified personnel. If E04 persists, arrange for heater pump unit repair or replacement.

Professional Required 5/5

Heater Element / Heater Relay on PCB

Check Price on Amazon

We may earn a commission from links on this page.