Heat-pump performance will deteriorate without regular maintenance and service. The difference between the energy consumption of a well-maintained heat pump and a severely neglected one ranges from 10 to 25 percent.
Regular Maintenance
- Clean or replace filters regularly (every 2 to 6 months, depending on operating time and amount of dust in the environment).
- Clean outdoor coils as often as necessary (when dirt is visible on the outside of the coil).
- Remove plant life and debris from around the outdoor unit.
- Clean evaporator coil and condensate pan every 2 to 4 years.
- Clean the blower’s fan blades.
- Clean supply and return registers and straighten their fins.
Professional Service
- Inspect ducts, filters, blower, and indoor coil for dirt and other obstructions.
- Diagnose and seal duct leakage.
- Verify adequate airflow by measurement.
- Verify correct refrigerant charge by measurement.
- Check for refrigerant leaks.
- Inspect electric terminals, and if necessary, clean and tighten connections, and apply nonconductive coating.
- Lubricate motors, and inspect belts for tightness and wear.
- Verify correct electric control, making sure that heating is locked out when the thermostat calls for cooling and vice versa. Verify correct thermostat operation.
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