Poolex pool heater runs but pool water does not reach set temperature or heats very slowly.

Safety: Turn off power before cleaning coils or opening panels.

Steps:

• Verify sizing and expectations: Compare your pool volume and desired temperature rise with the Poolex model's rated kW output. In cold weather, heating will be slower.
• Clean air coil: Gently wash the evaporator coil with low-pressure water and a soft brush to remove dust and debris.
• Optimize water flow: Ensure valves are correctly set and filters are clean so the Poolex titanium heat exchanger receives adequate flow.
• Check operating hours: Run the heater continuously for 24–48 hours during initial heat-up; heat pumps are slow but efficient.

If performance remains poor, a technician should check refrigerant charge and system pressures.