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Florida house, first summer

Florida Homeowner AC Maintenance Checklist

Your AC has to run long enough to pull the water out of the air. That's how a Florida house stays dry. Stuff the filter, or let the drain line plug, and it quits early. Then it's 74 and still sticky. Look at the filter every month. Change it when it's dirty. Three months is the longest you'd wait. A plugged drain line can flood the house and make it muggy. Day to day, leave the fan on Auto. Free list. I'm not selling you a visit. Don't take the box apart.

Where this stops. Monthly stuff you can do. Filter. Turning the cooling off before you pull it. Checking the drain line. Pouring at that little T on the pipe by the indoor box. The fan setting. How to shut it down for a storm or a trip. Don't take the box apart. Need a new size? That's a real load calc, not this page. Water through the ceiling, or it smells like it's burning? Mode Off, then the outdoor shutoff (the switch in the box by the outdoor unit), then call a local AC person.

This month’s checklist

Tap a box as you go. It stays on this phone until you clear it. Print if you want a paper copy.

Why this matters in Florida

If the AC keeps starting and stopping, it never pulls the water out. That's the whole problem here. A stuffed filter and a slimy drain both make the run shorter. Auto on the fan lets it drip dry in between. Still guessing what size you need? Use the AC tonnage calculator for Florida homes. Between two sizes, the smaller one usually keeps you less sticky here. A real load calc settles it. Comparing the numbers on an old unit? That's the SEER2 savings calculator. Cooling only, Orlando rates, not a quote.

Vinegar or bleach?

Think of it like a pool. Nobody scrubs a pool clean. You keep the water somewhere nothing wants to live. Same trick in a smaller pipe. Vinegar tips it one way. Bleach tips it the other. The slime doesn't like either. Nothing from the pool shed goes down an AC drain.

Once a month: power off. Pour a cup of distilled vinegar at the little T on the pipe by the indoor box. Unscrew the cap. If it splashes, you've made salad.

Already plugged? Shop vac on the outdoor pipe. Vinegar will not pull dirt. Two jobs.

Bleach instead: half a cup. Once in a while. Never monthly.

Never mix them. Bleach and vinegar make chlorine gas. Same for bleach and any other cleaner. One or the other. Period.

This is a list for you, not a service call. ENERGY STAR still wants a local AC person to look at the system before summer. There's no form here and no phone number. Call whoever you already trust.

Common questions

How often should I change the filter in Florida?

Look at it every month. Dirty means change it. ENERGY STAR says 3 months even when it looks OK.

Fan On or Fan Auto?

Auto, day to day. House still feels off after a clean filter and a clear drain? Flip to On for a while and see. If Fan On is the only thing keeping the rooms from going swampy, that’s a symptom. Call a local HVAC tech before humidity assigns you overtime.

When do I use the outdoor shutoff?

After Mode Off, and only when you actually need the power gone. Filter change, drain work, a storm coming. It's the switch in the box by the outdoor unit. Not a light switch.

Can I just use bleach in the drain line?

Half a cup. Once in a while. Never monthly. Never mix it with vinegar or anything else.

Sources (retrieved Aug 31, 2026)