AC Not Cooling? 7 Checks | Mendoza Heating and Air

It's 88° in the house and the thermostat says it's trying. Before you call anyone — including us — run through these seven checks. I'm serious: about half the "AC not cooling" calls we get are one of these, and a few take two minutes. We'd rather you fix it free than pay us to flip a breaker. (And when it's not one of these, you'll know it's real — and we'll be out fast.)

The 7 checks

1. Thermostat: cool mode, set below room temp. Sounds insulting, we know. But "someone bumped it to heat" or "the kids set it to 85" accounts for more calls than you'd believe. Set it to COOL, fan to AUTO, and at least 3 degrees below the room temp. Wait 5 minutes.

2. The breaker. Find your electrical panel. The AC breaker (often labeled AC, A/C, or condenser) should be fully ON — not sitting in the middle. If it's tripped, flip it fully off, then on. If it trips again immediately, stop — that's an electrical fault, call us.

3. The air filter. Pull it out and hold it to the light. If you can't see light through it, it's choking your system — restricted airflow can literally freeze the indoor coil into a block of ice. Swap it ($5 at any hardware store) and give the system an hour.

4. The outdoor unit: clear and running? Walk outside. Is the condenser running (fan spinning, humming)? Is it buried in bushes, leaves, or grass clippings? It needs two feet of clearance on all sides to breathe. Clear it off — but don't stick anything into the fins.

5. Look for ice. Check the copper lines going into the outdoor unit and peek at the indoor coil if you can. Ice or heavy frost = turn the system OFF at the thermostat but leave the fan ON to thaw, then call. Running it frozen can kill the compressor.

6. The condensate drain / float switch. Tampa humidity means gallons of water drain out of your system daily. If the drain clogs, a little float switch shuts the whole system down to save your ceiling from flooding. If your system just stopped with no warning, this is suspect #1 — and it's a quick fix for a tech.

7. All the vents open? Closed vents in "unused" rooms don't save money — they raise system pressure and can freeze the coil or trip safety switches. Open them all up.

wil’s take

“I’d rather talk you through a breaker flip on the phone for free than charge you a service call for it. But if you’ve done these seven and it’s still not cooling — that’s a real problem, and real problems don’t fix themselves. Call.”

— wil, owner

When to stop checking and call

Call us right away if: the breaker trips repeatedly, you see ice you can't explain, there's water where it shouldn't be, you hear grinding or loud buzzing from the outdoor unit, or you smell burning. Those aren't DIY items — they're "shut it off and call" items. We run 24/7 emergency service, nights and weekends included, because AC problems don't check the clock.

The pattern behind most no-cool calls

Here's what years of Tampa summers taught us: the systems that quit on the hottest day almost always showed warning signs first. Weak airflow for a week. Running longer cycles. A little ice that melted and came back. The $75 tune-up exists precisely to catch this stuff before it's a 9pm emergency — a weak capacitor found in October is a ten-minute fix; the same capacitor dying in July is an emergency call.

Questions & Answers

Why is my AC not cooling but the fan is running?

The indoor fan running with no cool air usually means the outdoor unit isn't doing its job — tripped breaker, failed capacitor, or a frozen coil. Check the breaker and filter first; if the outdoor unit is silent or iced over, call before it gets worse.

Can a dirty air filter stop my AC from cooling?

Yes — a clogged filter chokes airflow, which can freeze the indoor coil into a block of ice. No airflow, no cooling. It's a $5 fix and one of the most common no-cool causes we see.

Should I turn my AC off if it's not cooling?

If you see ice on the lines or the coil, yes — turn the system off but leave the fan ON to thaw it, and call. Running a frozen system can damage the compressor, turning a small fix into a big one.

How fast can someone come out for a no-cool call?

We run 24/7 emergency service across Tampa Bay — nights, weekends, holidays. No-cool calls jump the line. Call (813) 770-2722.

Still not cooling?

You've done the checks — now it's our turn. 24/7 emergency AC repair across Tampa Bay.

Call (813) 770-2722 Same Day Service

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