How to Prepare Your AC for Summer 2026

Spring is the perfect time to get your air conditioner ready for the hot months ahead. A little preparation now prevents breakdowns in July and keeps your energy bills in check. Here is a complete checklist for every AC type.

Universal Steps (All AC Types)

1. Clean or replace the air filter. This is the number one thing you can do. A dirty filter reduces efficiency by 5-15%. See our filter cleaning guide for details.
2. Check the thermostat. Replace batteries if needed. Consider upgrading to a programmable or smart thermostat if you have central AC.
3. Test the system. Turn it on before the first hot day. Run it for 15-20 minutes and verify it blows cold air and there are no unusual noises or smells.
4. Clear the area around the unit. Both indoor and outdoor components need unrestricted airflow.

Window AC Checklist

• If stored for winter, inspect the unit for any damage or rust
• Clean the coils with a soft brush or compressed air
• Check the window seal and foam insulation strips — replace if worn
• Verify the unit tilts slightly backward for proper drainage
• Clean the drain hole with a thin wire or pipe cleaner

Central AC Checklist

• Remove any plywood or debris covers from the outdoor unit
• Clear vegetation within 2 feet of the outdoor condenser
• Hose down the condenser fins gently (from inside out)
• Inspect the refrigerant lines for damage or missing insulation
• Pour vinegar down the condensate drain line to prevent clogs
• Schedule a professional tune-up ($100-$150 — worth every penny)

Mini-Split Checklist

• Clean the indoor unit filters and wipe down the housing
• Use a coil cleaning spray on the evaporator (available at hardware stores)
• Check the outdoor unit for leaves, dirt, or animal nests
• Verify the condensate drain is clear and flowing
• Test the remote control batteries

Portable AC Checklist

• Drain any remaining water from the internal tank
• Clean the filter
• Inspect the exhaust hose for cracks or holes
• Check that the window kit seals properly
• Run it for 30 minutes and check for water leaks or unusual noises

Pro Tips for Maximum Efficiency

• Set the thermostat to 78F when home, higher when away — each degree lower increases energy use by 3-4%
• Use ceiling fans to supplement AC (lets you raise the thermostat 4 degrees without losing comfort)
• Close blinds on south and west-facing windows during afternoon hours
• Seal air leaks around windows and doors with weatherstripping
• Avoid running heat-generating appliances (oven, dryer) during peak heat hours