Surviving Inland Empire Summers: Keeping Your AC Running Through a Heat Wave
When temperatures hit triple digits, AC systems fail at the worst possible time. Here's how to keep yours running strong — and what to do the moment it quits.
Owner & Lead HVAC Technician, Alex Air & Heating · EPA 608 Universal Certified · Ontario, CA
TL;DR
To keep your AC alive through an Inland Empire heat wave, replace a dirty filter, clear two feet around the outdoor unit, close blinds on sun-facing windows, and hold the thermostat at 78°F rather than pushing it lower. On a 100°F-plus day most systems can only pull indoors about 20°F below outdoors, so a house that will not reach 72°F is usually at its physical limit, not broken.
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Anyone who's spent a July in Ontario, Riverside or Fontana knows the Inland Empire doesn't do summer halfway. When the thermometer pushes past 100°, your air conditioner is working harder than at any other time of year — and that's exactly when tired systems give out. A little preparation goes a long way toward making it through the heat without an emergency.
Why heat waves break air conditioners
During a heat wave, your AC may run almost continuously to maintain temperature. That nonstop demand exposes any weakness — a marginal capacitor, a low refrigerant charge, a dirty coil, or a clogged filter — and turns a small issue into a full failure. The systems that fail in August are usually the ones that skipped their spring tune-up.
Before the heat hits: get ahead of it
- Replace your air filter so airflow is at its best.
- Hose off the outdoor condenser and clear two feet of space around it.
- Schedule a tune-up in spring — before the rush, not during it.
- Listen for new noises and watch for weak airflow now, while a repair is routine.
During a heat wave: help your system keep up
- Set a steady temperature rather than cranking it way down — your AC can only cool so fast.
- Close blinds and curtains on sun-facing windows to block radiant heat.
- Run ceiling fans to feel cooler so you can ease off the thermostat slightly.
- Avoid the oven and heat-generating appliances during the hottest hours.
- Set the thermostat fan to AUTO, not ON, so you're not circulating un-cooled air.
Warning signs your AC is struggling
Catch these early and you can often avoid a total breakdown:
- It runs constantly but can't reach the set temperature.
- Airflow is weak or the air isn't as cold as it used to be.
- New rattling, buzzing or grinding sounds.
- Ice on the refrigerant lines or indoor unit.
- A breaker that trips when the AC kicks on.
What to do the moment it quits
If your AC stops during a heat wave: turn the thermostat off so the system doesn't keep straining, check the filter and breaker, and move somewhere cool while you wait. Don't repeatedly reset a tripping breaker — that's an electrical problem that needs a pro. Then call us. We keep our trucks stocked for the common heat-wave failures so we can often fix them on the first visit.
Don't tough out triple-digit heat with a broken AC. Call Alex Air & Heating at 626-777-4822 for fast, same-day AC repair across the Inland Empire & LA County — and ask about our maintenance membership so next summer starts with peace of mind.
We run same-day and emergency AC repair across Ontario, the Inland Empire and East LA County, with an upfront written price before any work starts. Emergency AC repair