Preparing Your AC for Summer: Spring Checklist

The first hot day of the year is when everyone discovers their AC isn’t working—and HVAC companies are booked for weeks. A little spring preparation ensures your system is ready to keep you cool all summer and catches problems before you’re desperate.

Spring AC Checklist

1. Replace the Air Filter

Start cooling season with a fresh filter:

• Remove and inspect your current filter
• Install a new filter rated for your system
• Write the installation date on the filter frame
• Set a reminder to check monthly during heavy use

A clean filter is essential for proper airflow and cooling efficiency.

2. Clear and Clean the Outdoor Unit

Your condenser needs clear airflow:

Remove debris:

• Clear leaves, twigs, grass clippings from around the unit
• Maintain 2 feet of clearance on all sides
• Trim back any vegetation that’s grown close

Clean the unit:

1. Turn off power at the disconnect and breaker
2. Remove large debris by hand
3. Gently spray coils with a garden hose (not pressure washer)
4. Allow to dry completely before restoring power

If you covered it for winter:

• Remove the cover completely before running the system
• Running AC with a cover causes serious damage

3. Inspect Refrigerant Lines

Check the copper lines running between your indoor and outdoor units:

• Look for damaged or missing insulation (foam covering)
• Check for signs of oil stains (may indicate refrigerant leak)
• Ensure lines aren’t kinked or crushed
• Replace damaged insulation to maintain efficiency

4. Check the Condensate Drain

Your AC removes humidity, which drains away:

Locate the drain line:

• Usually a white PVC pipe near the indoor unit
• Drains to outside, floor drain, or utility sink

Clear potential clogs:

1. Pour a cup of white vinegar into the drain access point
2. Wait 30 minutes
3. Flush with warm water
4. Verify water flows freely out the exit point

A clogged drain can cause water damage and trigger system shutoffs.

5. Test Your System

Before you need cooling:

1. Set thermostat to cooling mode
2. Lower temperature 5 degrees below current room temp
3. Wait for the system to start (both indoor and outdoor units)
4. Feel for cool air at vents within 5-10 minutes
5. Let it run 15-20 minutes

Check for:

• Both indoor and outdoor units running
• Cool air from vents (not room temperature)
• No unusual sounds
• No unusual smells
• Condensate drain working (dripping outside)

6. Check Thermostat Settings

Prepare for cooling season programming:

• Switch from heat to cool mode
• Set comfortable temperatures
• Review and update schedules
• Replace batteries if applicable
• Test both fan-only and cooling modes

Consider upgrading to a smart thermostat for better efficiency.

7. Inspect Indoor Components

Check accessible indoor equipment:

• Supply and return vents are open and unobstructed
• Return vent filters (if equipped) are clean
• No water stains or damage around indoor unit
• Condensate pump (if equipped) is working

8. Check Electrical Connections

Basic electrical verification:

• Disconnect switch at outdoor unit is on
• Circuit breakers for AC and air handler are on
• No visible wire damage at outdoor unit
• No burn marks or corrosion at disconnect box

Any electrical concerns warrant professional inspection.

9. Schedule Professional Maintenance

Annual professional tune-ups keep your system running efficiently:

What’s included:

• Refrigerant level check and adjustment
• Electrical connection inspection and tightening
• Coil cleaning (indoor and outdoor)
• Blower motor inspection
• Thermostat calibration
• System performance testing
• Safety checks

Best timing:

• Schedule in early spring before the busy season
• Maintenance plans often include priority scheduling

10. Check Windows and Insulation

Your cooling efficiency depends on your home’s envelope:

• Check weatherstripping on doors and windows
• Verify attic insulation is adequate
• Inspect window caulking
• Consider reflective window film for sun-facing windows
• Ensure ceiling fans rotate counterclockwise for cooling

Troubleshooting Common Spring Startup Issues

System Won’t Start

• Verify thermostat is set to cool
• Check circuit breakers
• Confirm outdoor disconnect is on
• Replace thermostat batteries

Runs But Doesn’t Cool

• Confirm outdoor unit is running
• Check for dirty filter
• Look for ice on refrigerant lines (indicates problem)
• Ensure vents are open

Short Cycling (Turning On/Off Repeatedly)

• May indicate dirty filter
• Could be refrigerant issue
• Possibly oversized system
• Needs professional diagnosis

Water Around Indoor Unit

• Condensate drain may be clogged
• Drain pan may be cracked
• Needs attention before water damage occurs

Summer Energy Efficiency Tips

Maximize cooling while minimizing costs:

• Set thermostat to 78°F when home, higher when away
• Use ceiling fans to feel 4 degrees cooler
• Close blinds on sun-facing windows during peak hours
• Avoid heat-generating activities during hottest parts of the day
• Don’t set temperature extremely low—it won’t cool faster
• Keep vents open in all rooms
• Change filter monthly during heavy use

Warning Signs That Need Attention

Call for service if you notice:

• Ice forming on refrigerant lines or indoor coil
• Water leaking around indoor unit
• Warm air from vents despite system running
• Unusual sounds (grinding, screeching, banging)
• Frequent cycling
• Significant increase in energy bills
• Burning or musty smells

Addressing issues early prevents mid-summer breakdowns when service is hardest to get.

Preparing for Extreme Heat

During heat waves:

• Run AC continuously rather than turning it on/off
• Keep windows and doors closed
• Use exhaust fans after cooking or showering
• Avoid using the oven during peak heat
• Pre-cool your home in the morning if possible

Your AC has limits—during extreme heat, it may not reach your set temperature. This is normal, not a malfunction.