Seasonal Guide

Preparing Your AC for Summer

Summer AC failures happen most often during the first heat wave of the season -- when systems that sat idle all winter are pushed to full capacity before any problems have been caught. A 30-minute pre-season check prevents most of these failures.

Step 1: Visual Inspection

  • Check the outdoor condenser unit for winter damage -- ice, debris, bent fins, or physical damage to the casing
  • Confirm the disconnect box on the outdoor unit is in the ON position
  • Check for nesting animals that may have sheltered in the unit during winter -- birds, rodents, and wasps commonly nest in outdoor units
  • Ensure there is 2 feet of clearance around the unit on all sides
  • Inspect the refrigerant lines (copper pipes with insulation) for damage or insulation deterioration

Step 2: Filter and Airflow Check

  • Replace the air filter -- start summer with a fresh filter regardless of how long the current one has been in
  • Walk through the house and confirm all supply vents are open and unobstructed
  • Confirm return air grilles are clear of furniture, rugs, or stored items
  • Check that the condensate drain is clear (pour water into the access port to test)

Step 3: First Start-Up Test

  • Set the thermostat to COOL and lower the setpoint 5 degrees below current room temperature
  • Listen for abnormal sounds -- grinding, squealing, rattling, or loud clicking from the outdoor unit
  • Go outside and confirm the outdoor fan is spinning and the compressor is running (you will hear it operating)
  • After 15-20 minutes of operation, hold your hand near a supply vent -- air should feel noticeably cool, ideally 16-22 degrees F cooler than return air temperature
  • Note any issues: warm air, system that starts and immediately shuts off, or unusual sounds. These warrant a service call before peak heat season.

Step 4: Schedule Professional Service

If your system passed the startup test, a professional tune-up is still recommended annually. Refrigerant pressure, capacitor condition, and coil cleaning are best handled by a technician with proper tools. Schedule in March-May before peak demand.

If the startup test revealed problems (not cooling, unusual sounds, short-cycling), schedule a diagnostic call promptly -- before summer demand makes wait times longer and emergency calls more likely.

Frequently Asked Questions

How do I prepare my AC for summer?
Key steps: replace the air filter, clear the area around the outdoor condenser, check that all vents are open, test the system by running it for 15-20 minutes and confirming cool air output, and schedule a professional tune-up if you have not had one in the past 12 months.
Should I turn on my AC before it gets hot?
Yes -- test your system on a moderately warm day (75+ degrees F) before the first heat wave. Running the system for 20-30 minutes lets you identify problems while wait times for service are still short. A system that fails in April is easier to repair than one that fails during a heat wave in July.
Why does my AC not work after winter?
Common causes: the circuit breaker tripped over winter and needs to be reset, the condensate float switch is stuck (pour water to free it), a capacitor or contactor failed over the off-season, or animals nested in the outdoor unit and caused damage. Test the breaker and thermostat first, then call a technician if the system still does not start.

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