Document LTM0883 rev 2a

 

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Fault Codes

A fault code indicates a specific issue or condition that will require action before the equipment can resume operating.

Please perform the following troubleshooting.

If the issue reoccurs, please contact the installing dealer. Or contact AquaCal® for a service partner in your area. See "Contacting AquaCal AutoPilot, Inc."

WARNING - Failure to heed the following may result in injury or death.

  • Repairs must not be attempted by untrained or unqualified individuals.
  • The heat pump contains refrigerant under high pressure. Repairs to the refrigerant circuit must not be attempted by untrained or unqualified individuals. Service must be performed only by qualified HVAC technicians. Recover refrigerant before opening the system.

CAUTION - Failure to heed the following may result in equipment damage.

  • Service by unauthorized personnel will void the heat pump warranty.

ClosedFLO Indicator

ISSUE

Low or no water detected.

RESOLUTION

  1. Confirm the filter pump is on.
  2. If a multiple-speed filter pump is being used, run at a higher speed to determine if the error persists. Do not exceed maximum flow rate for your model.
  3. Confirm water is not being diverted away from the heat pump.

ClosedCEr Indicator

ISSUE

This can indicate a loose or damaged communication cable.

RESOLUTION

A qualified technician should check the cable from control board to display assembly for a loose connection or visible damage.

ClosedCSE Indicator

ISSUE

This is a control system error.

RESOLUTION

Deactivate then reactivate power to reset controls.

CloseddpC or dPO Indicator

ISSUE

Shorted or open defrost sensor.

RESOLUTION

A qualified technician should replace the defrost sensor.

ClosedpC or pO Indicator

ISSUE

Shorted or open water sensor.

RESOLUTION

A qualified technician should replace the water sensor.

Closed HP Indicator

ISSUE

The refrigerant system’s high-pressure switch is showing as open.

RESOLUTION

If the heat pump is a reversing unit, place it in HEA mode and perform the following troubleshooting.

Determine if an insufficient amount of water is being supplied to the equipment.

  1. Confirm the filter pump is on.
  2. If a multiple-speed filter pump is being used, run filter pump at a higher speed. Do not exceed maximum flow rate for the model.
  3. Confirm water is not being diverted away from the heat pump.

ClosedHP5 Indicator

ISSUE

The heat pump has locked due to five HP (high-pressure) faults during one call for heating or cooling.

RESOLUTION

  1. Deactivate then reactivate power to the heat pump to clear error.
  2. Troubleshoot the high-pressure issue causing the error. See " HP Indicator"

ClosedLP Indicator

ISSUE

The refrigerant system’s low-pressure switch is showing as open.

RESOLUTION

If the heat pump is a reversing unit, place it in HEA mode and perform the following troubleshooting.

  1. Check for proper fan operation. If fan is not operating, contact AquaCal® Technical Support.
  2. Check for obstructed air flow around the heat pump. See "Clearances"
  3. Check for dirty or blocked evaporator coil. See "Cleaning Equipment"
  4. Check for signs of ice buildup on the coil.

ClosedLP5 Indicator

ISSUE

The heat pump has locked due to five LP (low-pressure) faults during one call for heating or cooling.

RESOLUTION

  1. Deactivate then reactivate power to the heat pump to clear error.
  2. Troubleshoot the low-pressure issue causing the error. See "LP Indicator"

ClosedOtA Indicator

ISSUE

Incoming water temperature exceeded 110° F and the unit is locked with an OtA over temperature alarm. The heat pump will not operate until incoming water temperature drops to 100° F or lower.

RESOLUTION

  1. Determine if another heat source (gas heater, solar heater, etc.) is heating water being sent directly to the heat pump with the OtA indicator. This situation will need to be corrected before continuing.
  2. Rule out an incorrect reading from the water temperature sensor. Verify existing water temperature with an accurate thermometer. If heat pump’s sensor is inaccurate, the water temperature sensor may require replacement.