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Duality Heating and Air

Heating

Heat you can count on when Denver drops below zero.

Furnace repair, replacement, and tune-ups from a NATE-certified tech who knows what a mile of altitude does to a gas furnace. Same-day service. Written price before any work. No overtime fees, ever.

  • $99 furnace diagnostic
  • Same-day across Denver
  • Written price first
Get Help Fast (720) 447-0177

Good to know

  • Set up for 5,280 feetThinner air changes how gas burns. Every furnace we touch is calibrated for Denver’s pressure and oxygen.
  • CO check on every visitA combustion and carbon monoxide test comes with every heating call, no extra charge.
  • Same price at 2 a.m.Nights, weekends, and holidays never carry an overtime fee.

$99 Furnace diagnostic. Credited toward the repair.

Who we are

Hello. We’re Duality.

Duality Heating and Air LLC is a Denver heating and cooling company run by one licensed technician and the people he trusts. We fix furnaces, ACs, heat pumps, and the air in your home, and we do it the way we’d want it done at our own house. Comfort, in perfect balance.

  • Denver-based

    One technician who lives here, not a call center in another state.

  • Price in writing

    You approve the number before we touch a tool. It never changes.

  • Fix before replace

    We repair what can be repaired and show you both numbers when it can’t.

Common problems we fix

Sound familiar?

  • Blowing cold air

    Usually the igniter, flame sensor, or a safety switch. Most are fixed on the first visit.

  • Starts and stops

    A furnace that cycles every few minutes is overheating or oversized. We find out which before we recommend anything.

  • Yellow or flickering flame

    A combustion problem that can make carbon monoxide. Shut it off and call us now.

  • Gas bill keeps climbing

    Older furnaces send a fifth of your money up the flue. A modern unit, up to 99% efficient, keeps most of it in the house.

  • Banging or rattling

    Delayed ignition, loose panels, or ducts expanding. Cheap to fix early. Expensive to ignore.

  • No heat at all

    Thermostat, breaker, or a dead motor. Our dispatcher walks you through the quick checks while the truck is on its way.

Get Help Fast

$99 Furnace diagnostic. Credited toward the repair.

What’s included

Everything under heating.

The $99 diagnostic covers the trip and a full inspection. You approve a written price before we touch a tool. If you go ahead, the $99 comes off the repair.

How pricing works Financing and rebates
  • Furnace repair on every brand, same-day across the metro
  • High-efficiency and Low-NOx furnace installation, derated for Denver altitude
  • Mini split heating for rooms without ducts
  • Cold-climate heat pump and dual-fuel systems
  • Carbon monoxide safety check on every heating visit
  • $99 seasonal tune-up with a written report

Good questions

Heating FAQ.

How fast can you get here if my heat is out?

Same day across the Denver metro, usually within a few hours for no-heat calls in winter. Nights and weekends never cost extra.

Repair or replace my furnace?

If the unit is under 12 years old and the repair is less than a third of a new one, we almost always say repair. Past 15 years, or with a cracked heat exchanger, replacement is the safe and cheaper call. We show you both numbers and let you decide.

Does altitude really matter for a furnace?

Yes. At 5,280 feet a gas furnace has to be properly calibrated for the difference in pressure and oxygen, and a lot of installers skip it. A furnace that isn’t set for Denver short-cycles, soots up, and quietly has issues. We set every unit up for here.

All homeowner questions

Related problems

Real Denver neighbors

  • Cecilia Gomez

    Google review
    “Professional, knowledgeable, and incredibly helpful. He took the time to explain everything clearly, answered all of my questions, and made the entire process easy and stress-free. I truly appreciated his honesty, responsiveness, and attention to detail.”

  • Jessica Russman

    Google review
    “Very honest and reliable. He showed up on time and fixed our old AC after we had several companies try to sell us a new one. We would 1000% recommend Duality to anyone who wants to feel confident they’re dealing with the right company.”

  • Jake Henriksson

    Google review
    “Punctual, communicative, and extremely professional without being a corporate robot. He tells the truth and gets things done. And he’s a one-man team, so things aren’t going to get lost in translation. 100% recommend.”

What to expect

Your visit, step by step.

  1. 01

    You send the form

    A few taps, or call or text. About 30 seconds.

  2. 02

    We call you back

    A Denver dispatcher confirms the address and window.

  3. 03

    Price in writing

    Flat-rate, before any work. You say yes or no.

  4. 04

    The fix

    Most repairs finish on the first visit. Parts on the truck.

Ready When You Are

Tell Us What's Wrong. We'll Call You Back in Minutes.

Three quick taps. A real Denver dispatcher calls to confirm your address and get a truck moving. No call center, no waiting on hold.

  • Written flat-rate price before any work starts
  • Same-day service across the Denver metro
  • No overtime fees, nights and weekends included

Prefer to talk? (720) 447-0177, open 24 hours.

Request service

Step 1 of 4 About 30 seconds
What do you need?
Step 2 · What’s going on?

Step 4 · Who should we call?

A real person calls you back, usually within minutes. 24/7.

Private and secure. We may call or text this number about your request. Reply STOP to opt out.

Two taps and a phone number. Or just call (720) 447-0177.

Where we do this

More services

(720) 447-0177Call now. We answer 24/7. Book a Service