May is the sweet spot for AC prep in Illinois. The weather is mild, HVAC technicians are still available (before the summer rush), and you have time to address any problems before you actually need the system. Here's a complete checklist for Homer Glen and southwest Chicago suburb homeowners.
DIY Tasks You Can Do Right Now
✓ Replace the Air Filter
Start fresh for cooling season. If you haven't changed your filter since winter, do it now. Use a MERV 8–11 filter for good filtration without restricting airflow. Set a reminder to check it monthly through September.
✓ Clear the Area Around Your Outdoor Unit
Your outdoor condenser needs at least 2 feet of clearance on all sides. Remove any debris, leaves, or vegetation that accumulated over winter. Trim back shrubs and bushes. This is especially important in May when cottonwood seeds are flying — they can clog the condenser coils quickly.
✓ Gently Rinse the Outdoor Unit
With the system turned off at the disconnect switch, use a garden hose to gently rinse the condenser coils from the outside in. Don't use a pressure washer — it can damage the fins. This removes accumulated dirt and improves heat transfer efficiency.
✓ Check and Clean Your Vents and Registers
Walk through your home and make sure all supply and return vents are open and unobstructed. Vacuum the grilles to remove dust buildup. Make sure furniture, rugs, and curtains aren't blocking airflow.
✓ Test the System Before You Need It
Turn on your AC on a mild day (when the outdoor temperature is above 60°F — running AC when it's colder can damage the compressor). Set the thermostat to COOL and a temperature below the current room temperature. Let it run for 15–20 minutes. The air coming from vents should feel noticeably cool. If it doesn't, call for service now — not in July.
✓ Check Your Thermostat Batteries
If your thermostat uses batteries, replace them at the start of each season. A failing battery can cause erratic behavior or complete thermostat failure.
✓ Inspect Refrigerant Lines
Look at the insulated copper lines running from your outdoor unit into the house. The insulation should be intact — if it's cracked, missing, or deteriorated, it reduces efficiency and should be replaced. This is a quick, inexpensive fix.
Professional Tasks — Schedule Now
✓ Annual AC Tune-Up
A professional tune-up covers everything you can't easily check yourself: refrigerant levels, electrical connections, capacitor and contactor condition, coil cleaning, thermostat calibration, and a full system performance test. Todd's HVAC Services offers AC tune-ups for $49 throughout Homer Glen, Orland Park, Tinley Park, Mokena, and surrounding areas. May slots are filling up — call now.
✓ Duct Inspection (If You Haven't Had One Recently)
Leaky ducts can waste 20–30% of your cooled air before it reaches your living spaces. If you've noticed uneven cooling, high energy bills, or rooms that never seem to get comfortable, a duct inspection is worth scheduling.
✓ Dryer Vent Cleaning (Annual)
While you're scheduling HVAC service, add dryer vent cleaning to the list. The U.S. Fire Administration recommends annual cleaning. Signs you need it: clothes taking longer than one cycle to dry, the dryer running hot, or a burning smell.
When To Call Todd's HVAC
If your AC doesn't cool properly during your test run, makes unusual noises, or shows any of the warning signs covered in our 7 Signs Your AC Won't Make It Through Summer article, call us before the summer rush hits.
Todd's HVAC Services serves Homer Glen, Orland Park, Tinley Park, Mokena, Frankfort, New Lenox, Lockport, Lemont, Romeoville, and surrounding southwest Chicago suburbs. Call or text 708-742-7935 to schedule service.
Related: AC Running But Not Cooling? Here's Why | How to Lower Your Electric Bill This Summer