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
Frequently asked questions
Request an assessment when there is a safety concern, the system stops operating, the issue repeats, or confirming the cause would require opening equipment or touching electrical connections.
No. A guide can help you understand the questions and observations, but system condition, compatibility, and scope can only be confirmed from the equipment and site.
Note the symptom, when it began, thermostat settings, and any visible damage from a safe distance. If it is accessible without removing panels, the equipment model can also help.
Alex Air & Heating serves Ontario, the Inland Empire, and East Los Angeles County. Appointment availability is confirmed against the current schedule.
Local next step
Turn this guide into a site-specific answer.
Guides explain the decision. Equipment condition, access, and safe next steps still need to match the home or business. Review the relevant service scope or request an assessment for Ontario, the Inland Empire, or East Los Angeles County. Availability depends on the current schedule.