CO
AquaCal
Communication Error with External Controller
Display shows CO or COMM; heater does not respond to remote commands.
Advertisements
Safety Warning
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.
Advertisements
Possible Causes
Broken or reversed communication wires, Incorrect protocol settings between AquaCal and automation system, Faulty communication interface board, Electrical noise on low‑voltage lines
How to Fix / Troubleshooting
Safety first: Turn off low‑voltage power to automation and heater before changing wiring.
- Check wiring polarity: Verify that the communication wires (e.g., RS‑485 A/B) are landed on the correct terminals at both the AquaCal interface and the pool automation panel.
- Inspect cable: Look for splices, corrosion, or damage along the communication cable run. Replace damaged sections.
- Verify settings: Ensure the AquaCal control is configured for external control and that the automation system is set to the correct heater type and address.
- Test standalone: Disconnect the communication cable and operate the heater from its local keypad. If it works locally, the issue is with the external controller or interface.
- Replace interface board: If wiring and settings are correct but CO persists, the AquaCal communication/interface board may need replacement.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
Communication Interface Board
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements