Display shows HE or HEAT ERR, spa does not heat even though pump runs.

Safety first: Turn off power at the GFCI breaker. Heater testing involves live voltage and should be done by a qualified technician.

• 1. Check for other codes: Ensure there are no flow-related codes (FLO, dr) that would prevent heating. Resolve those first.
• 2. Inspect heater connections: With power off, tighten heater terminal screws on the Coleman control pack and inspect for discoloration or melting.
• 3. Resistance test: A technician can disconnect the heater leads and measure resistance across the element. An open circuit indicates a failed heater that must be replaced.
• 4. Relay function: If the heater tests good but never receives power when heat is called for, the heater relay on the control board may be stuck open or burned and the board will need replacement.
• 5. Replace heater assembly: If the heater is cracked, leaking, or electrically open, replace the complete heater assembly with a Coleman-compatible unit, ensuring proper sealing of unions and sensor ports.