How to Clean a Heat Pump Outdoor Unit

Clean your heat pump's outdoor unit by turning off power, removing debris, washing the coils with a garden hose, and clearing the area around the unit. This should be done every 3-6 months to maintain efficiency.

  1. Kill Power First. Switch off the heat pump at your home's electrical panel or disconnect box near the outdoor unit. Wait at least 30 minutes for any electrical components to discharge before beginning work. This safety step prevents electrical shock and protects the system's components.
  2. Clear the Debris. Clear away leaves, twigs, grass clippings, and any other debris from around and on top of the unit. Use your hands or a small brush to remove material stuck between the fins. Be gentle with the aluminum fins as they bend easily and damage affects airflow.
  3. Rinse the Coils. Spray the coils from inside the unit outward using a garden hose with moderate pressure. Never use a pressure washer as it will damage the delicate fins. Work from top to bottom, ensuring water flows in the same direction air normally moves through the coils. This removes dirt, pollen, and grime that blocks airflow.
  4. Restore Fin Alignment. Use a fin comb or butter knife to carefully straighten any bent aluminum fins you notice. Work gently and only straighten fins that are significantly bent. Proper fin alignment ensures maximum airflow through the coils, which directly affects your system's efficiency.
  5. Flush the Drain. Locate the drain pan at the bottom of the unit and remove any standing water or debris. Pour a cup of warm water mixed with a tablespoon of dish soap through the drain to ensure it flows freely. A clogged drain can cause water damage and reduce system efficiency.
  6. Clear Around Unit. Cut back any bushes, plants, or grass within 2 feet of the unit on all sides and 5 feet above. Proper clearance ensures adequate airflow and prevents debris from accumulating on the coils. Mark this area and maintain it regularly throughout the growing season.
  7. Power Up and Listen. Turn the power back on at the electrical panel and set your thermostat to call for heating or cooling. Listen for unusual noises and watch for proper operation. The unit should start smoothly and run quietly. If you notice problems, contact a technician before continued operation.