When both your furnace and central AC are pushing 15 years old at the same time, the decision gets genuinely interesting. Replacing one system while keeping an aging partner rarely makes financial sense, and that overlap is exactly when the math on a heat pump shifts in your favor. We’ve been installing heating and cooling systems across Arvada and the Greater Denver area since 1983, and the dual-replacement scenario is the most common situation where homeowners benefit from slowing down and comparing all three options before signing anything.
There’s also a lot of outdated information circulating right now, particularly around incentives and cold-weather performance. Before you make a decision based on a tax credit that no longer exists or assumptions about heat pumps that applied to equipment from a decade ago, it’s worth getting the current picture.
How Each System Actually Heats Your Home
A gas furnace burns natural gas and produces supply air typically between 110 and 140 degrees Fahrenheit, regardless of how cold it is outside. The heat is immediate and intense, which is part of why furnaces have dominated Colorado homes for decades. A heat pump doesn’t generate heat through combustion at all. It moves heat that already exists in outdoor air using refrigerant, concentrating it and transferring it inside. This works on a principle similar to how a refrigerator operates in reverse.
Modern cold-climate heat pumps, rated by the HSPF2 efficiency standard, maintain full heating capacity down to about 5 degrees Fahrenheit and continue operating down to negative 15. That’s a meaningful shift from older technology, which genuinely did struggle in deep cold. Arvada sits between 5,100 and 5,500 feet above sea level, with foothills neighborhoods approaching 5,800 feet, well within the range where today’s cold-climate units perform at their best.
What Denver Winters Actually Demand
Denver metro winter overnight lows typically run between 5 and 25 degrees Fahrenheit, with occasional Arctic fronts dropping to around negative 10. For the vast majority of the heating season, a cold-climate heat pump operates at or near full capacity throughout that range. On the coldest peak days, a gas furnace holds a clear comfort advantage because it can produce higher supply air temperatures on demand.
Gas furnaces installed in Colorado require a high-altitude combustion adjustment. At elevations above 2,000 feet, the air is less dense, which affects the air-to-fuel ratio inside the combustion chamber. Without proper orifice resizing and derating, a furnace can lose 10 to 20 percent of its rated output and may produce elevated carbon monoxide levels. This isn’t a fringe concern. It’s a safety and efficiency issue that makes installer qualification genuinely important. Our NATE-certified technicians account for this on every furnace installation we perform. Heat pumps don’t combust fuel, so the altitude adjustment doesn’t apply to them.
Proper sizing matters for any system, which is why we use Manual J load calculations (a room-by-room assessment of your home’s insulation, window area, duct layout, and square footage) before recommending equipment capacity. A heat pump sized by square footage alone is often wrong.
The Real Cost Comparison: Upfront, Operating, & Incentives
Installed costs in the Denver metro currently run roughly $8,500 to $16,500 for a cold-climate heat pump system, and $6,500 to $12,000 for a high-efficiency gas furnace. If your central AC also needs replacement, add $4,500 to $10,000 for a separate cooling system. When both the furnace and AC are due at the same time, the total cost gap between a heat pump and the combined furnace-plus-AC route narrows considerably. Sometimes the heat pump is the less expensive path before incentives.
Xcel Energy’s Efficiency+ program currently pays $2,250 per ton for qualifying cold-climate heat pumps, with no income requirement for Xcel gas customers. Colorado’s state heat pump tax credit adds $1,000 on top of that. These programs stack and can meaningfully reduce the net cost of installation. One correction worth making clearly: the federal 25C energy efficiency tax credit expired on December 31, 2025 and is no longer available. Several articles published around that date still cite it as a current benefit. Rebate programs also change, so we always recommend verifying current Xcel and state program details before making a final decision. We can walk through the current incentive picture during a free estimate.
The Third Option Most Homeowners Miss: Dual-Fuel Systems
A dual-fuel hybrid system pairs a cold-climate heat pump with a gas furnace in a single installation. The heat pump handles all the heating work during moderate weather, which covers the overwhelming majority of Denver’s annual heating hours. When outdoor temperatures drop below the switchover point (typically somewhere between 15 and 30 degrees Fahrenheit, depending on equipment and local utility rates) the gas furnace takes over automatically. You get the efficiency of a heat pump for most of the season and the peak output of a gas furnace for the coldest days.
For homes in Arvada with existing gas service, this setup is often the most practical answer to the furnace-versus-heat-pump question because it doesn’t ask you to choose. We install dual-fuel systems for Arvada customers, including Carrier Infinity heat pump and furnace combinations completed in a single visit. As a Carrier Factory Authorized Dealer, we install and service the Carrier Infinity line, which includes qualifying cold-climate models that meet Xcel’s Efficiency+ rebate requirements.
Which System Fits Your Home
No single answer applies to every home. The right system depends on a combination of factors specific to your house.
A cold-climate heat pump or dual-fuel system tends to be the right fit when:
- Both your furnace and AC are 12 or more years old and due for replacement at the same time
- Your home has 200-amp electrical service with capacity to support a heat pump compressor
- You plan to stay in the home for at least seven years, long enough to recover the upfront cost through operating savings
- You have existing gas service that makes a dual-fuel configuration practical
A high-efficiency gas furnace rated at 96 percent AFUE (Annual Fuel Utilization Efficiency, the share of fuel that becomes usable heat) or higher tends to make more sense when:
- Only one system is at end of life and the other has years remaining
- Your electrical panel is 100 amps without budget or capacity for an upgrade
- Upfront cost is the primary constraint and the combined furnace-plus-AC route fits the budget better
Ductwork condition matters for both systems. Leaky or undersized ducts hurt either one, but heat pumps move higher volumes of air at lower temperatures than furnaces do, making duct integrity more noticeable. Insulation quality, window area, and ceiling height all factor into real-world performance, which is why load calculations come before any recommendation we make.
Getting to the Right Answer for Your Home
The heat pump versus furnace question has a correct answer for your specific home, your electrical service, your ductwork, and your timeline. The dual-fuel path resolves the tradeoff for a lot of Arvada homeowners, but only when the equipment is sized right and the installation accounts for Colorado’s altitude from the start. Our free estimates include an honest look at your existing ductwork, electrical panel capacity, and current equipment before we recommend anything. If you’re ready to sort out which direction makes sense, Coffman & Company is glad to walk through it with you. Give us a call at (720) 600-6887.