Rated 4.7 out of 5

4.7 Google rating from 432 reviews

Furnace Repair in Denver, CO

We find what failed, price the fix, and wait for your yes.

Call Summit

Rated 4.7 out of 5

4.7 Google rating from 432 reviews

Furnace Repair in Denver from a Team That Explains the Fix First

Summit diagnoses your furnace, shows you what failed and what the fix costs, and waits for your yes before any repair starts. At Summit Heating, A/C, Plumbing & Electrical, our technicians repair gas furnaces for homeowners across Denver and the surrounding metro. When your furnace quits, blows cold air or keeps shutting off, you want two things: a straight answer about what broke, and a price before anyone touches a wrench. That is how we work. Your technician finds the cause, explains it in plain terms, and gives you the repair price first. Google reviewers describe it the same way: “wasn’t pushy,” “NO upselling.”

Denver furnaces carry a long season. NOAA’s 1991-2020 normals for Denver International Airport show about 5,863 heating degree days a year and an average January low of 18.7°F (checked November 2026). A furnace that limps through October can fail on the first hard cold night, so it pays to call when you first notice a problem.

HVAC diagnostic: $99.95.

How Our Furnace Repair Visit Works

1. You call or book online

We schedule a visit during business hours.

2. Diagnosis

Your technician tests the furnace, finds the failed part or fault, and shows you what they found. The HVAC diagnostic is $99.95.

3. Estimate review

Your technician reviews the estimate with you. You can approve it on the spot or later through a link to the estimate.

4. Repair

Once you approve, we make the repair, then test the furnace to confirm it heats.

5. Cleanup

We clean the work area before we leave.

We take calls Monday to Friday, 7am to 6pm, and Saturday and Sunday, 8am to 3pm. After hours: our answering service takes your call and we call back the next business day. We don’t advertise hours we can’t keep.

Signs Your Furnace Needs Repair

No heat at all

Power, thermostat, ignition or gas supply problem

Furnace lights, runs a few seconds, then shuts off

Ignition or flame-sensing problem, or a safety switch tripping

Blower runs but the air is cold

Burners not lighting or not staying lit

Furnace runs constantly and the house stays cold

Airflow restriction, failing part or a system too small for the load

New banging, squealing or grinding

Blower motor, belt or burner issue

Breaker trips when the furnace starts

Electrical fault in the furnace

These are common causes. Your technician confirms the real one at your house before quoting anything.

Before You Call: Three Quick Furnace Checks

Some no-heat calls end at the thermostat, so check these first:

The thermostat is set to heat, and the set temperature is above the room temperature. Replace its batteries if it has them.
The furnace switch (it looks like a light switch near the unit) is on, and the furnace breaker is not tripped.
The furnace filter is not clogged. A badly blocked filter can make some furnaces shut themselves down.

If those look fine and you still have no heat, call (720) 870-1580.

Furnace Repair Cost in Denver

HVAC diagnostic: $99.95. That is the fee for the visit and diagnosis. We don’t publish repair price ranges because the price depends on the part and the furnace. You see the exact repair price before we start.

Ask about our maintenance memberships, or book a furnace tune-up before the heating season.

What Changes the Price of a Furnace Repair

The failed part: An igniter or sensor costs far less than a blower motor or control board.
Furnace brand and model: Part prices and availability differ by manufacturer.
Access: Attic and tight crawlspace installs take longer to work on.
Number of problems: The estimate covers every fault the diagnosis finds, listed separately.

Repair or Replace Your Furnace: We Start With Repair

We treat repair as the first option wherever a repair is real. Furnace age, the condition of the heat exchanger and burners, and how often the furnace has needed repairs all affect whether a repair makes financial sense. If we think replacement is the better call, we show you why and put both options in writing. Then you decide.

Colorado’s rules don’t force a repair decision. HB23-1161 says new gas furnaces and water heaters sold in Colorado since January 1, 2026 must meet ultra-low-NOx limits (or be ENERGY STAR). Repairs to your existing furnace are unaffected (Colorado General Assembly, checked November 2026). If you do replace, we cover the options on our furnace replacement page.

Denver Furnace Permits, Codes and Altitude

Permits. Replacing a forced-air furnace in a Denver single-family home or duplex requires a quick permit from Denver Community Planning and Development. If your repair turns into a replacement, we pull the permit (checked November 2026).
Codes. Denver works from the 2025 Denver Building and Fire Code, based on the 2024 International Codes (checked November 2026).
No heat pump mandate for homes. Energize Denver and Denver’s heat-pump-on-replacement rules apply to commercial and multifamily buildings, not single-family homes (checked November 2026).
Altitude. Gas furnaces along the Front Range are set up to the manufacturer’s high-altitude instructions, which vary by model.

Our Written Guarantees on Every Heating Job

We Stand Behind Our Work

If a repair or installation issue is caused by our workmanship, we will return and make it right at no additional charge within the applicable warranty period.

Honest Recommendations

We will explain our findings, provide honest recommendations, and never pressure you into purchasing services or equipment you don't need.

Respect for Your Home

Our technicians will treat your home with care, maintain a clean work area, and conduct themselves professionally.

Your Satisfaction Matters

If you are unhappy with your service experience, give us the opportunity to address your concerns. We will listen, investigate, and work toward a fair resolution.

We Take Responsibility

If we make a mistake, we own it. We believe in accountability and doing what is right for our customers.

Google Reviews of Summit Heating, A/C, Plumbing & Electrical

Summit holds a 4.7 rating from 432 Google reviews (as of Nov 4, 2026). Here is what heating customers wrote.

"Our first encounter was a heating issue - they were able to apply a simple fix, and recommended a new thermostat."

John Google review (heating repair)

"I had the pleasure today of having Christian come out to my house and provide services for my furnace. Christian was on time, polite and professional."

Milton Google review (furnace service)

Related Heating Services Near Denver

Related Furnace and Heating Services

Furnace and Heating Repair in Nearby Cities

We repair furnaces across Denver, including Highland, City Park West, Valverde, College View and University Hills, and in nearby areas we serve, including Littleton, Ken Caryl and Highlands Ranch. Service is the same in every area. See our service area page for all three trades in the city.

Furnace Repair Questions from Denver Homeowners

How much does furnace repair cost in Denver?

The HVAC diagnostic is $99.95. The repair price depends on the failed part, your furnace model and access, so we quote it after the diagnosis. You see the price before any work starts, and you can approve it on the spot or later through a link to the estimate.

Does the $99.95 diagnostic come off the repair price?

No. The HVAC diagnostic is $99.95 whether or not you go ahead with the repair. We post it so you know the cost of the visit before you book.

Will you try to sell me a new furnace?

Not unless replacement is the better option for you, and then we show you why. One of our written service guarantees says we will explain our findings, provide honest recommendations, and never pressure you into purchasing services or equipment you don’t need.

Book a Furnace Diagnostic in Denver

Call (720) 870-1580 to book a furnace diagnostic. Prefer to book online? Request service.

Furnace Repairs