Heil air conditioner runs but does not cool well; supply air is only slightly cooler than room temperature

Safety first: Turn off power to the air handler before opening panels. Refrigerant work must be done by a licensed technician.

• Step 1 – Replace filter: Install a new filter of the correct size and MERV rating for your Heil system.
• Step 2 – Clean indoor coil: Remove the access panel to the A-coil. Use a soft brush and approved coil cleaner to remove dust and debris. Do not bend fins.
• Step 3 – Check outdoor coil: Clean the condenser coil as described earlier to improve heat rejection.
• Step 4 – Measure temperature drop: With the system running 15–20 minutes, measure temperature at a return grille and a supply grille. A typical drop is 16–22°F. If much lower, call a technician to check refrigerant charge and compressor performance.