Why Is My Heat Pump Not Cooling on Hot Days?

A heat pump that won’t cool on hot days usually has an airflow problem, a refrigerant issue, or a control setting that’s working against you. The most common cause we see is restricted airflow from a dirty filter or a clogged outdoor coil, which makes the system run but move little cooling. High heat also exposes weak capacitors, failing outdoor fan motors, or low refrigerant from a leak. We handle these cooling calls often in the Westlake Corner area. We also offer same-day heat pump repairs with no extra charge for overtime.

Try these fast checks before you call:

• Set the thermostat to Cool and fan to Auto (not Heat or On).
• Replace a dirty filter and clear debris from the outdoor coil.
• If you see ice on the lines or feel warm air from vents, call a pro.
• Nonstop running, breaker trips, or an older undersized unit need evaluation.

If the outdoor unit is hot to the touch and barely moving air, shut the system off to prevent damage and schedule service. <br/> Updated: 2026-03-31 <br/> Need help in Westlake Corner, VA? Call 5406851594 or book online. "Kenneth did a great job installing a new heat pump. The whole Ostrum experience has been very positive." — Chris R.