Homeowners across Colorado are increasingly turning to cold climate heat pumps for year-round comfort and energy efficiency. Whether you live in Littleton, Castle Pines, Highlands Ranch, or anywhere along the Front Range, these systems offer a smart alternative to traditional HVAC setups—especially in colder months.

But to get the performance you need in Colorado’s winter conditions, not just any heat pump will do. The ENERGY STAR® Cold Climate Certification ensures you’re installing a system that’s built to perform when temperatures drop.

Here’s what that certification really means—and why it matters.

What Is an ENERGY STAR® Cold Climate Certified Heat Pump?

ENERGY STAR® certification with a Cold Climate designation (Version 6.1) means a system has been tested and proven to:

• Deliver reliable heat in freezing conditions
• Maintain high efficiency in both heating and cooling modes
• Require less backup heating from electric resistance or a furnace

To earn the certification, a heat pump must meet the following technical benchmarks:

SEER2 (Seasonal Energy Efficiency Ratio 2): ≥ 15.2

• Measures cooling efficiency over the course of an entire cooling season
• A higher SEER2 rating means the system uses less electricity to provide air conditioning
• A SEER2 of 15.2 or greater ensures strong performance in Colorado’s warm summers

EER2 (Energy Efficiency Ratio 2): ≥ 11.7

• Indicates how efficiently a heat pump cools your home during peak demand periods, such as the hottest days of the year
• It’s a snapshot of energy performance at full load conditions
• A minimum EER2 of 11.7 means better real-world performance when your system is working hardest

HSPF2 (Heating Seasonal Performance Factor 2): ≥ 9.5

• Measures heating efficiency across an entire heating season
• A rating of 9.5 or higher means the unit provides more heat per unit of energy used
• This is particularly important in Colorado, where heating season energy costs can add up quickly

COP at 5°F (-15°C): ≥ 1.75

• COP stands for Coefficient of Performance, and it evaluates how efficiently a heat pump generates heat at low outdoor temperatures
• At 5°F, the system must produce at least 1.75 units of heat for every 1 unit of electricity consumed
• This metric is critical for homeowners in Colorado, where sub-freezing temperatures are common

Heating Capacity at 5°F Must Be ≥ 70% of Capacity at 47°F

• This ensures the heat pump maintains most of its heating output in very cold weather
• If the system’s output at 5°F is at least 70% of what it can produce at 47°F, it reduces dependence on backup heat
• It’s a key sign the system can be relied on even during the coldest nights in Colorado

Why This Matters for Colorado Homeowners

Many standard heat pumps begin to lose efficiency—or even stop working effectively—when temperatures drop below freezing. That’s not just a comfort issue; it also impacts energy use, cost, and overall system reliability.

Installing a cold climate certified system ensures:

• Reliable performance in sub-freezing temperatures
• Better efficiency and lower energy bills
• Compatibility with Colorado utility rebate programs
• Less need for backup heating systems

Why Choose ROX Heating & Air?

Not every HVAC contractor understands how to properly design, install, and commission cold climate heat pump systems—especially in Colorado’s unique climate zones. At ROX Heating & Air, we’ve positioned ourselves as Colorado’s heat pump experts, and here’s why that matters:

• We specialize in cold climate heat pump systems, not just standard installations
• Our team understands the specific ENERGY STAR® performance criteria and selects systems that meet or exceed those benchmarks
• We stay up to date with Colorado rebate programs (like Xcel Energy rebates) and help you navigate them to maximize your savings
• We design systems that are custom-tailored to your home, ensuring comfort and long-term performance in all seasons
• Every install includes proper documentation, AHRI certification matching, and performance verification to ensure your system qualifies for rebates and performs as expected

We’re not just here to install equipment—we’re here to make sure your investment in high-efficiency heating and cooling delivers the comfort, reliability, and savings you expect.

Ready to Learn More?

We offer free, no-pressure estimates and take the time to explain your options, rebate opportunities, and system performance in detail—so you can make the best decision for your home.

Schedule your free estimate today and find out why more Colorado homeowners are trusting ROX Heating & Air with their cold climate heat pump installations.