Spring AC Prep Checklist: 8 Things to Do Before It Hits 100°
March and April are the cheapest months to have your AC serviced. Here's the pre-season checklist that prevents mid-summer failures.
By June, every HVAC company in the Valley is booked out 5–10 days for tune-ups and 2–3 days for emergency repair. March and April are the smart months. Here's the pre-season prep list.
1. Book your spring tune-up
Ideally by end of March. Every year we see the same pattern: 60% of AC failures happen in the two-week window when the first 100°+ days hit. Systems that were coasting on borderline capacitors, marginal refrigerant charge, and clogged drains give up under load. A March tune-up catches most of it.
2. Replace the filter
Even if it doesn't look bad, put in a fresh one at the start of cooling season. Clean baseline for the summer.
3. Clear the outdoor unit
Winter accumulates dust, blown-in oleander leaves, mesquite pods, and irrigation overspray residue on the outdoor coil. Rinse gently with a garden hose from inside out (unscrew the top grille if you can). Trim any plants back to at least 24" of clearance around the unit.
4. Test cooling mode
Set the thermostat to COOL, drop the setpoint 3° below room temp, and confirm you get cold air within 10 minutes. If it takes longer, or the supply is warm, don't wait for July to call — book a diagnostic now.
5. Check the condensate drain
Find the primary drain access on your air handler (usually a T-fitting with a small cap). Pour a cup of white vinegar down it. This prevents biofilm buildup that clogs drains mid-summer.
6. Confirm the attic float switch works
Reach up to the air handler drain pan and lift the float on the safety float switch. The system should shut off. If it doesn't, the switch is defective and needs to be replaced before summer.
7. Program the thermostat for summer
Set your summer schedule now. For SCE time-of-use plans, pre-cool the house before 4 PM peak, then let temperature drift a few degrees during peak, then recover after 9 PM. Saves noticeable money over holding a single setpoint all day.
8. Note the equipment location
If you rent or bought recently: photograph your equipment nameplates (outdoor unit, indoor unit) and save them. When we ask "what tonnage is your system?" during a service call, you'll have the answer.
Bonus: change your batteries
Thermostat batteries, smoke detector, CO detector. The pre-summer batch is a good annual habit.
Book your spring tune-up — best price of the year and open scheduling before the crush.
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