DIY spring HVAC tune-up in 30 minutes

Five tasks that take 30 minutes and cost under $30 keep your system running efficiently all summer. Do this in March-April before the first hot day.

Steps

1. Replace the air filter ($10-$30): Use MERV 8 for most homes (best balance of filtration and airflow). MERV 11 for allergy-prone households. Filtrete and Nordic Pure are top-rated budget options. Replace every 60-90 days.
2. Clean the outdoor condenser unit: Turn off power at the disconnect box. Remove leaves, grass clippings, and debris from around and inside the unit. Hose down the fins gently from inside out. Maintain 2 feet of clearance around the unit.
3. Straighten bent condenser fins: Use a fin comb ($8-$12 at hardware stores) to straighten bent aluminum fins. Bent fins restrict airflow and reduce efficiency by 5-10%.
4. Flush the condensate drain line: Pour 1 cup of white vinegar into the drain line access point (usually a PVC pipe near the indoor air handler). This prevents algae clogs that cause water backups and water damage.
5. Inspect supply and return vents: Remove vent covers, vacuum dust buildup, and ensure no furniture or rugs are blocking airflow.

Tips

• A dirty filter alone can increase energy consumption by 5-15%
• In humid southern climates, flush the condensate line monthly through summer — algae clogs are the #1 AC service call
• Write the date on the filter with a marker so you know when to replace it