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Troubleshooting Guide for Gulfstream Heat Pumps

Gulfstream Technical Support: 239-939-7446


A simple test to verify that your heater is functioning is to place your hand above the unit. There should be cool air blowing out the top after time delay has expired. The return water to the pool should be a few degrees warmer than water entering the heater. After about 15 minutes of run time, there should be water draining out of the base of the unit.

If you have reason to believe your heater is not functioning properly, follow the troubleshooting guide below or call the factory for service.

Control Displays "LOW FLOW"
POSSIBLE CAUSE: The pool pump is not on. A valve is turned, bypassing the water through the heater. Clogged water line, filter or pump impeller. Internal water pressure switch failure.
POSSIBLE SOLUTION: Turn pool pump on. Clean pump and filter. Adjust water valves. If problem persists, call factory for service.

Control Displays "DEFROSTING"
POSSIBLE CAUSE: Ambient air is too low for heater to function.
POSSIBLE SOLUTION: Unit will turn back on once ambient air rises to appropriate level.

Control Displays "LOW REFRIGERANT PRESSURE"
POSSIBLE CAUSE: Refrigerant leak.
POSSIBLE SOLUTION: Call factory for service.

Control Displays "HIGH REFRIGERANT PRESSURE"
POSSIBLE CAUSE: Water flow restriction, valve is turned restricting flow.

POSSIBLE SOLUTION: Clean pump and filter. Adjust water valves. If problem persists, call factory for service.

Control Displays "HP3 Water Lockout
POSSIBLE CAUSE: Water flow restriction, valve is turned restricting flow.

POSSIBLE SOLUTION: Clean pump and filter. Adjust water valves. If problem persists, call factory for service.

Control Displays "HIGH WATER TEMPERATURE"POSSIBLE CAUSE:
Heater control malfunction. Secondary source of heat.

POSSIBLE SOLUTION: Call factory for service.

Control Displays "EVAP SENSOR MALFUNCTION"
POSSIBLE CAUSE: Defrost sensor malfunction or not connected.
POSSIBLE SOLUTION: Call factory for service.

Control Displays "WATER SENSOR MALFUNCTION"
POSSIBLE CAUSE: Water sensor malfunction or not connected.
POSSIBLE SOLUTION: Call factory for service.

Pool is heating slowly or not getting up to temperature.
POSSIBLE CAUSE: Low or restricted water flow through the heater. Leak in plumbing allowing air into the water flow. It is cold outside. Pump timer is not set for a long enough run time. Pool is not being covered. High wind speed over pool. Pool area shaded.
POSSIBLE SOLUTION:Clean or replace filter. Inspect and clean pool pump. Adjust water valves. Repair air leaks. Use a pool cover. Construct a wind break around pool. Set pool pump timer longer. Call factory for service.

Water is running out of the bottom of the heater.
POSSIBLE CAUSE: The heater produces up to 3 gallons per hour of water condensing from the evaporator coil. Internal water leak.
POSSIBLE SOLUTION: Shut the heater off for several hours and leave the pool pump running. If the water is still running out, call factory for service.