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Which of these sounds like you?

Name: Swiss Air Heating & Cooling
Address: 406 E Wabash St, O'Fallon, MO, 63366, US
Telephone: (636) 978-7800

Broken AC, a replacement you're pricing, a new house, a quote you're unsure about — pick your situation and get the shortest honest path through this site.

Something's broken. Right now.

First: if you smell gas or a carbon monoxide alarm is sounding, get everyone outside and call 911 from out there, before anything else, including us. For everything short of that, the emergency guides walk you through the first minutes: what to check safely yourself, and the signals that mean stop and call. We answer 24/7.

Emergency guides: what to do first → , Six scenarios, no heat, AC out in a heat wave, gas smell, frozen line, tripping breaker, leaking water heater, each with the first steps in order.
No heat in winter: the 5-minute checklist → , Thermostat, switch, breaker, filter, blower door. It restores heat in a meaningful share of calls before a truck rolls.
AC out in a heat wave → , What to check, how long it's safe to wait, and the heat-illness signals that make this urgent.
Book emergency service →

My system's on its last legs. I'm planning the replacement.

Good position to be in: replacing on your schedule beats replacing during a heat wave. The honest order of operations is fit first, then price, then money. Figure out which system type actually suits your house, see what these systems really cost installed in this market, and check the rebates before you sign anything.

Which system fits your home? → , A five-minute wizard that matches system types to your actual house, ducts, size, priorities, with honest pros and cons.
What an HVAC system really costs → , Real installed ranges for the St. Louis market, and what legitimately moves the price versus what's padding.
Repair or replace? → , The honest math for deciding whether this system deserves one more fix first.
Rebates, credits & financing → , Ameren Missouri rebates and current incentives materially change the total, check them before comparing bids.
Get a written quote →

Nothing's wrong. I just want to understand this stuff.

Welcome, this is the part of the site we're proudest of. Everything is open: how each system works, side-by-side comparisons, and the maintenance habits that prevent most of the emergencies on this site. No sign-up, nothing gated, no salesperson at the end unless you ask for one.

The Learning Center → , Every guide in one place: how systems work, homeowner Q&A, and honest comparisons.
How heat pumps work → , The system everyone's asking about, explained without the hype, including how it handles Missouri winters.
Home safety, season by season → , CO safety, freeze protection, humidity control, storm-season surge defense, tuned to St. Louis weather.
The filter change guide → , The five-minute habit that prevents the most common failures we see. Genuinely the best place to start.
Browse the Learning Center →

We just moved in, new house, new state, no idea who to call.

Welcome to the neighborhood, St. Louis weather asks a lot of a heating and cooling system, and the smartest first move is knowing what you actually have. Walk the house once with the homebuyer checklist (it works just as well after closing), get the system's age and condition on paper, and put maintenance on a schedule so the seasons stop surprising you.

The homebuyer HVAC inspection checklist → , What a general home inspection barely touches: system age, condition, ductwork, and the red flags, checkable room by room.
The seasonal maintenance checklist → , What to do in spring and fall, what's yours versus a technician's, and when to schedule each piece.
Home safety for Missouri seasons → , Humid summers, cold snaps, thunderstorm season, the guides that explain what this climate does to a house.
Meet the company → , Family-owned in O'Fallon since 1989, see exactly who shows up before you need anyone to.
See the USA Savings Club →

I have a quote in my hand and something feels off.

Trust the instinct, asking is free, literally. Send us the quote and a licensed Swiss Air expert reviews it at no cost, matching the scope exactly. If the other company's price and diagnosis are fair, we'll tell you so. We'd rather earn your trust than your money, and a padded quote is easiest to spot before you've signed it.

Free second opinion → , How it works, what to send, and what you get back, an honest read from a licensed expert, free.
Repair or replace? → , The framework for judging whether 'you need a whole new system' is diagnosis or sales strategy.
What an HVAC system really costs → , Real installed ranges for this market, so no quote gets to surprise you.
Why Swiss Air → , Who shows up matters: family-owned, technicians who aren't paid sales commissions, and guarantees in writing.
Send us the quote →

None of these quite fit? Everything is open to browse: the Learning Center, the comparisons, and the home safety guides, no sign-up, nothing gated.

Before you go

Why this page exists

Swiss Air has been family-owned in O'Fallon since 1989, and the five situations above aren't marketing inventions, they're the actual phone calls we take every day across St. Charles County and the St. Louis metro.

We built this page because the worst time to learn how a furnace works is the week yours fails. So read first. Take whatever time you need. Nothing here expires.

And one promise in writing: if you ask us to look at something and the honest answer is that it doesn't need replacing yet, that's the answer you'll get. It's the same promise behind our free second opinions.

Call (636) 978-7800 Get a free second opinion