Do Heat Pumps Work in Colorado? 5 Myths We Hear (And What’s Actually True)

• Heat pumps work in Colorado winters, including during polar vortex events. We have the data.
• They do use more electricity than a gas furnace uses gas. It’s physics. But operating costs depend on your setup.
• Modern cold-climate heat pumps (post-2019) are more reliable than the older models that earned heat pumps a bad reputation.
• Dual fuel systems exist for people who want gas backup. Many customers don’t need it.
• Not all “cold climate” heat pumps are the same. The label is a minimum standard, not a guarantee.

Short answer: Yes. We’ve installed over 12,000 heat pumps across the Denver metro and Front Range. They work. But “work” comes with caveats: not every heat pump, not every installer, and not every situation.

Here are the myths we hear constantly, what’s actually true, and what you need to know before buying.

This was true in the 1980s. It’s not true now.

What Changed

Around 2018-2019, manufacturers figured out cold-climate heat pump technology. Mitsubishi’s Hyper-Heating, Bosch’s IDS Ultra, and similar systems use flash injection compressors and variable-speed inverters that maintain heating capacity at temperatures the old systems couldn’t handle.

The spec sheets say these units operate down to -13°F or -22°F. But specs are just specs. Here’s what actually happened.

Real Data from Colorado’s Polar Vortex

During December 2022, Colorado’s Front Range hit -15°F, the coldest in 30+ years. We monitored heat pump systems across our service area.

Results:

• Supply air temperature: 88-89°F (compared to 110-120°F from a gas furnace)
• Indoor temps: Homes held at 68-69°F
• Backup heat activation: Most systems didn’t need it
• Failures: Zero among properly sized cold-climate units

The DOE ran a Cold Climate Heat Pump Technology Challenge across 23 sites in 10 states and 2 Canadian provinces. Systems operated successfully at -15°F.

This isn’t marketing. It’s field data.

The -13°F Rating Explained

Most cold-climate heat pumps are “rated” to -13°F. This confuses people.

It doesn’t mean the system stops at -13°F. It means:

• Above -13°F: Full rated capacity
• At -13°F: Efficiency drops to about 70-80% of rated output
• Below -13°F: System keeps running, capacity continues to decrease

Mitsubishi Hyper Heat units operate down to -22°F. They don’t hit a wall. Output decreases gradually as it gets colder.

In Denver, temps below -13°F are rare. When they happen, it’s usually overnight for a few hours. Your house has thermal mass. A properly sized system handles this.

This one is partially true. We’re not going to pretend otherwise.

The Honest Answer

Heat pumps use electricity. Gas furnaces use natural gas. In Colorado, natural gas is cheap, around $1.10/therm. Electricity runs about $0.14/kWh.

At 40°F, a heat pump with COP 3.5 (meaning it produces 3.5 units of heat for every 1 unit of electricity) costs about the same per BTU as a 95% efficient gas furnace.

At 0°F, COP drops to 1.8-2.2. Gas wins on operating cost per BTU delivered.

Why This Doesn’t Tell the Whole Story

• Most of winter isn’t 0°F. Denver’s average winter temperature is in the 30s and 40s. The days when gas is cheaper are a small fraction of total heating hours.
• Heat pumps also cool. If you’re replacing both a furnace AND an air conditioner, the comparison changes. One system does both jobs.
• Dual fuel systems exist. You can pair a heat pump with a gas furnace. Heat pump runs above 30-35°F (most of winter). Gas kicks in below that. Best of both worlds.

When All-Electric Makes Sense

• You’re building new and don’t want to run a gas line
• You have solar panels
• You’re in Boulder or another municipality pushing electrification
• Your gas furnace is newer and you’re adding a heat pump for AC anyway (dual fuel)
• You want to eliminate combustion appliances from your home

When Dual Fuel Makes Sense

• You have a working gas furnace
• You want the lowest possible operating costs
• You want gas backup for extended cold snaps
• You’re skeptical and want insurance

We don’t push one over the other. It depends on your situation.

Our data says the opposite.

What We’ve Seen

Over 12,000 heat pump installations in the past several years. Our callback rate on Mitsubishi Hyper-Heating systems is lower than our callback rate on gas furnaces.

Why? Fewer moving parts in the critical path. No gas valve, no igniter, no flame sensor, no heat exchanger cracks. The compressor either works or it doesn’t, and modern inverter compressors are remarkably durable.

What Actually Causes Heat Pump Problems

• Wrong equipment. A standard heat pump installed in Colorado will struggle. It needs to be cold-climate rated, and not all “cold climate” labels are equal.
• Bad installation. Incorrect refrigerant charge, improper sizing, poor unit placement. A heat pump installed by someone who treats it like a basic AC swap will underperform.
• Undersizing. A heat pump sized for cooling won’t keep up with heating demand. Proper sizing requires a Manual J calculation based on your home’s actual heat loss.

When heat pumps fail to perform, it’s almost always one of these three issues. The technology itself is solid.

Brands That Struggle in Colorado

We’ve replaced enough equipment from other installers to have opinions:

• Daikin: Capacity issues in cold weather. Marketing doesn’t match our experience.
• Lennox: Frequent compressor failures. Pattern, not fluke.
• MrCool: DIY units from big box stores. Not designed for cold-climate performance.
• Rheem: Mid-tier equipment that can’t keep up here.
• Fujitsu multi-zone: Single-zone is fine. Multi-zone systems struggle.

Brands That Work

• Mitsubishi Hyper-Heating (H2i): Over 4,000 installed. Lowest callback rate.
• Bosch IDS Ultra: 600+ installed. Solid cold-weather performance.
• Carrier Infinity 25VNA4 / 37MUH: Newer to our lineup, performing well.

This fear comes from two places: old technology and bad installations.

How Modern Systems Handle Extreme Cold

A properly sized cold-climate heat pump maintains temperature through a polar vortex without backup. We have customers who’ve never used their backup heat strips through multiple Colorado winters.

But backup options exist:

Electric resistance strips: Built into the air handler. Expensive to run, but only activate during extreme cold. For the 2-5 days per year it’s truly brutal, they work fine.

Dual fuel: Heat pump paired with gas furnace. The heat pump handles 90%+ of heating hours. Gas kicks in when temps drop below a setpoint (usually 30-35°F). Higher upfront cost, lowest operating cost, maximum peace of mind.

Space heaters: Seriously. For a couple of nights per year, a $30 space heater in a bedroom handles it. Some customers prefer this simplicity.

What “Working” Feels Like

Heat pumps deliver 85-95°F air continuously. Furnaces blast 110-120°F air in short bursts.

Both keep your house at 70°F. The heat pump just does it differently. Some people find the constant warm airflow more comfortable. Others miss the “blast of hot air” feel.

During extreme cold, expect:

• Continuous operation (normal, not a malfunction)
• Defrost cycles every 30-90 minutes (whooshing sound, steam from outdoor unit)
• Slightly lower supply air temps than mild weather

None of this means it’s not working.

They’re not. The “cold climate” label is a minimum standard, not a quality guarantee.

Three Different Definitions

Colorado regularly sees temperatures below 0°F. A unit that “passes” at 5°F can still leave you cold when you need heat most.

What to Look For

• Rated heating capacity at 5°F and below. If the spec sheet doesn’t list capacity at 0°F or -5°F, assume it can’t do it.
• Minimum operating temperature. Lower is better. Look for -13°F or below.
• COP at 5°F. Should be at least 1.75, preferably 2.0+.
• Brand-specific cold-climate designations:
  • Mitsubishi: Must say “H2i” or “Hyper-Heating”
  • Bosch: Must be “IDS Ultra” (not standard IDS)
  • Carrier: Look for 25VNA4 or 37MUH model numbers

How to Verify

Check the NEEP Cold Climate Heat Pump Database. Search by model number. Look at capacity retention at 5°F and minimum operating temperature.

Don’t take anyone’s word for it, including ours.

Heat pumps work in Colorado. The technology caught up around 2019. We’ve installed over 12,000 of them and have the data to prove they handle our winters.

But success depends on:

• The right equipment. Cold-climate rated from a reputable brand, not just any heat pump with the right sticker.
• Proper sizing. Manual J calculation, not rule-of-thumb guessing based on square footage.
• Competent installation. From someone who understands cold-climate heat pumps, not an AC contractor treating it like a standard swap.
• Realistic expectations. The air feels different than a furnace. Operating costs depend on your setup. Dual fuel exists for a reason.

If you’re getting quotes, ask contractors: “How many cold-climate heat pumps have you installed in Colorado? What’s your callback rate?” If they can’t answer confidently, that’s your answer.