Jandy AquaLink RS / iAquaLink WiFi-Enabled Pool & Spa Automation Controller with Mobile App Control HEATER COOL Error Fix: Heater Cooldown Cycle Active

Error code HEATER COOL on the Jandy AquaLink RS / iAquaLink WiFi-Enabled Pool & Spa Automation Controller with Mobile App Control means: Heater Cooldown Cycle Active. The pool heater is in its post-operation cooldown cycle — this is NORMAL operation, not an error; the pump continues running to circulate water through the heater and dissipate residual heat from the heat exchanger; do not turn off the pump or controller during the cooldown period; interrupting cooldown can cause overheating of the heat exchanger; the cooldown cycle typically lasts 1-3 minutes; wait for the message to clear before making system changes

The most successful fix is "Inspect and Service Heater Heat Exchanger and Pump" (medium difficulty, ~45 minutes). Estimated DIY cost: $10-$20. HomeMD has 2 community-ranked fixes for this error.

This error is rated medium severity. It should be addressed soon, but your appliance may still function in a limited capacity.

Yes — the top-ranked community fix ("Inspect and Service Heater Heat Exchanger and Pump") is rated medium difficulty and takes about 45 minutes. Tools needed: T25 Torx screwdriver, Adjustable wrench, Clamp meter, Garden hose.

DIY cost: $10-$20. Professional repair typically costs $120-$200. Many homeowners save money by trying the top-ranked community fix first.

The Jandy AquaLink RS / iAquaLink WiFi-Enabled Pool & Spa Automation Controller with Mobile App Control has 8 other known error codes, including: CHECK SYSTEM (General System Fault), COMM ERR (Communication Error — RS-485 Bus Failure), FREEZE PROT (Freeze Protection Mode Active), HIGH CURRENT (High Current Draw on Monitored Circuit), HIGH SALT (Salt Level Above Maximum), and 3 more.