The AC Mistake That Costs You $40/Month

June in DuPage County hits different. One week you’re in a sweater, and then suddenly it’s 91°F and your AC is running flat-out while your electric bill quietly stages a coup.

We’re a pressure washing company — not HVAC techs — but we know a thing or two about exterior maintenance. And the number of homes we clean where the AC condenser is caked in cottonwood, dirt, and debris? Startling.

Here’s the short version of what summer actually costs when your cooling system is fighting against you.

Most homeowners set their thermostat to a target temperature and walk away. That’s not wrong, but it’s not efficient either.

The Department of Energy’s recommendation: 78°F when you’re home, 85°F when you’re not. Every degree lower than 78°F adds roughly 3% to your cooling costs. If you’re keeping it at 70°F all summer, you’re paying a premium for comfort you may not even notice.

Programmable and smart thermostats handle this automatically. If you don’t have one yet, a basic programmable model runs $25–40. The payback period is usually a single billing cycle.

What to set:

Ceiling Fan Direction:

Counter-clockwise in summer. Pushes air down, creates a wind-chill effect. You can raise the thermostat 2–4 degrees and not notice the difference. Switch is on the motor housing.

Window Film:

Apply heat-blocking window film to south- and west-facing windows. $20–40 for a standard window. Blocks 55–70% of solar heat gain. Visible difference in rooms that cook in the afternoon.

Programmable Thermostat:

If you don’t have one, get one. Set it and forget it. The $30 version works fine. You don’t need smart features — you just need it to stop running the AC when nobody’s home.

Also, it had commitment issues with the thermostat. Classic.

(This newsletter comes with a money-back guarantee—oh wait, it's free. Nevermind.)

It also required remembering to close the windows at 7 AM before leaving for work. Spoiler: people forgot. A lot.

Modern equivalent: a programmable thermostat and blackout curtains. Boring, effective, and no one has to be awake at dawn. Aren’t you glad you live in 2026?

Modern equivalent: Vinegar and water. Boring, but your house won't explode. Aren't you glad you live in 2026?

We sat down with Mark Plunkett of @ Properties to talk about the biggest mistakes homeowners make before selling, how to maximize property value, and some of the wildest situations he’s encountered in real estate.

Q: Mark, what’s the biggest mistake homeowners make when selling their property?

Mark: “The biggest mistake homeowners make is trying to list the property before it’s truly ready. First impressions are everything — you only get one first impression. I always encourage my clients to wait until the property is fully prepared before going to market.”

Q: What’s a small issue that can become a big expensive problem if ignored?

Mark: “It really goes back to preparation. We call it ‘clean and green.’ Maybe it’s fresh paint, cleaning pavers, exterior washing, landscaping, or fixing small maintenance items. Buyers notice everything. If they see too many issues, they start mentally adding up repair costs and can lose interest quickly.”

Want to read the full interview? Mark shares the prep mistakes that cost sellers thousands, why buyers notice everything in the first five minutes, and why "clean and green" isn't just a nice idea — it's what separates a quick sale from a sitting listing.

🌈 Scottish Festival & Highland Games — Sat, June 13 · DuPage County Fairgrounds, Wheaton

Highland athletics, traditional music, dance competitions, and clan gatherings at the Fairgrounds. One of the better free-admission spectacles in DuPage County for a Saturday. Bring sunscreen.

📖 AAUW Naperville Used Book & Media Sale — Thu–Sat, June 11–13 · Mill Street Elementary, Naperville

Free admission. Thousands of books, media, and more. Proceeds benefit local scholarships. Friday night is Educators’ Appreciation Night. If you’ve been meaning to build up the summer reading pile, this is the weekend.

🛒 Elmhurst Farmers Market — Wed, June 11, 7AM–1PM · 149 W. Brush Hill Rd, Elmhurst

Running every Wednesday through October. Local produce, vendors, and a good reason to leave the house before it gets hot. Get there early.

Q: “Should I cover my AC unit in summer when it’s not running?”

Short answer: no. Covering a condenser traps moisture, encourages pests to nest inside, and creates the exact environment you’re trying to avoid. Covers are for winter, when debris and ice are the concerns. In summer, the unit needs airflow — covering it does the opposite of help.

Q: “My AC runs all day and the house still feels warm. What’s wrong?”

Three most likely culprits: clogged filter, refrigerant leak, or a condenser that needs cleaning. Start with the filter — it’s free to check and five dollars to fix. If that’s not it, call a tech. A system that runs constantly without cooling is already costing you money — diagnosis is cheaper than the bill.

Got a question? Reply to this email—you might see it featured next!

Quick question: when did you last look at the north side of your house? That’s where algae starts. That’s also where moisture sits longest after rain — right against your siding, your foundation, your window frames.

We’re Rolling Suds of Naperville–Elmhurst. We handle pressure washing, soft washing, exterior window cleaning, roof and gutter cleaning, concrete sealing, and the kind of deep exterior cleaning that makes a house feel reset before summer shows up for real.

Explore our services here
Rollings Suds of Naperville-Elmhurst
(630) 448-7014 | [email protected]