Heat Pump Efficiency
Heat pump efficiency is a measure of how effectively a heat pump transfers heat energy compared to the amount of electricity it consumes. Unlike traditional systems that generate heat, heat pumps transfer it, allowing them to achieve efficiency ratings of 300% to 500%.
For homeowners seeking long-term comfort, upgrading to an energy efficient heat pump offers a smart way to help lower energy bills while reducing environmental impact. Whether you are replacing a furnace or looking for an all-in-one heating and cooling solution, understanding efficiency ratings is the first step toward superior home comfort.
Are heat pumps more efficient than other HVAC systems?
Yes, heat pumps are significantly more efficient than traditional HVAC systems because they move heat rather than generating it. While high-efficiency gas furnaces typically top out at 98% efficiency, heat pumps can operate with efficiencies of 300% to 500% or more, depending on the model and conditions.
Because they handle both heating and cooling, air source heat pumps provide a versatile, year-round solution. Even in colder regions, modern cold climate heat pumps utilize advanced inverter technology to close the performance gap, making them a viable, energy-smart upgrade over traditional combustion systems.
Defining Important Efficiency Terms: SEER2, HSPF2, EER & COP
Heat pump energy efficiency is measured using specific ratings for heating and cooling modes. Understanding these metrics helps you choose the right system for your climate and budget.
The most common ratings for residential air-source heat pumps are:
- Seasonal Energy Efficiency Rating 2 (SEER2): Measures cooling efficiency.
- Heating Seasonal Performance Factor 2 (HSPF2): Measures heating efficiency.
Curtis Herchenbach, owner of Herchenbach Mechanical in Gurnee, IL, explains why it is important for homeowners to consider these ratings:
Checking the SEER2 and HSPF2 ratings ensures you select an AHRI-certified system and qualify for available rebates. These are the latest efficiency standards homeowners should consider.
For geothermal heat pumps, which rely on ground or water temperatures, efficiency is measured by:
- Energy Efficiency Ratio 2 (EER2)
- Coefficient of Performance (COP)
Seasonal Energy Efficiency Rating 2 (SEER2)
SEER2 measures a heat pump’s cooling efficiency over a typical cooling season. It is calculated by dividing the total heat removed from the home by the total electrical energy consumed.
- Why it Matters: A higher SEER2 rating means greater cooling efficiency and lower energy bills. Upgrading from an older unit (e.g., 8 SEER) to a modern 15.3 SEER2 model could save roughly 50% on energy costs.
- Minimum Requirement: As of 2023, the Department of Energy requires a minimum of 14.3 SEER2 for residential air-source split systems. Learn more about minimum efficiency standards.
- High Efficiency: Models rated 17 SEER2 and above are considered high efficiency heat pumps, with some top-tier models such as the 27VNA3 reaching up to 23 SEER2.
Heating Seasonal Performance Factor 2 (HSPF2)
HSPF2 measures a heat pump’s heating efficiency over the heating season. Think of it like miles-per-gallon for your car—a higher HSPF2 indicates a more efficient heat pump.
- Why it Matters: Higher HSPF2 ratings ensure your system uses less electricity to keep your home warm during winter.
- Minimum Requirement: The Department of Energy established 7.5 HSPF2 as the minimum standard for residential split-system heat pumps.
- High Efficiency: Systems with a rating above 9 HSPF2 are considered high-efficiency, with top performers such as Carrier's 27VNA1 hitting 12.5 HSPF2.
Energy Efficiency Ratio 2 (EER2)
EER2 measures a split heat pump’s cooling efficiency under a specific set of testing conditions. A higher EER2 indicates that the heat pump can provide more cooling output for the electricity it uses at that test condition, making it useful for comparing cooling efficiency among split heat pump models.
- Minimum Requirement: EER2 requirements vary by equipment type, size, and region, so the applicable federal or local minimum should be checked for the specific split heat pump.
- High Efficiency: Systems with a rating above EER2 are considered high-efficiency, with top performers such as Carrier's 27VPA9 hitting 14 EER2.
Coefficient of Performance (COP)
COP measures the heating efficiency of geothermal heat pumps at a fixed temperature.
- Minimum Requirement: 3.1 COP heating for closed-loop, water-to-water geothermal systems.
- High Efficiency: High-performing models can achieve ratings of 4.5 COP or higher.
Heat Pump Efficiency Requirements by Region
While the Department of Energy has established a uniform national minimum efficiency standard for heat pumps, specific requirements can vary based on your climate zone.
- North Region: Requires stricter efficiency standards to handle cold temperatures. Current standards under the M1 rating system require 13.4 SEER2 to ensure reliable heating.
- Southeast Region: Focuses on cooling performance due to hot, humid climates. The latest M1 standards require a minimum of 14.3 SEER2 (or 13.8 SEER2 depending on capacity).
- Southwest Region: Requires high standards for both SEER and EER due to intense heat. Standards require 14.3 SEER2 and 11.7 EER2 (depending on capacity) to maintain efficiency in extreme temperatures.
- Nationwide Minimum: For split system heat pumps, the federal minimum is 14.3 SEER2 and 7.5 HSPF2.
Factors that Influence Heat Pump Efficiency
Several factors beyond the unit's rating impact its real-world performance. Prioritizing these elements ensures you get the most out of your energy efficient heat pump.
1. Type of Energy Source
- Air-Source: The most common type. Transfers heat between indoor and outdoor air. Air-source heat pumps are cost-effective and versatile.
- Mini-Split Ductless: Ideal for homes without ductwork or for room additions. Mini-split ductless heat pumps avoid energy losses associated with ducts.
- Geothermal: Draws energy from the ground or water. These offer the highest efficiency but come with higher installation costs.
2. Ductwork Quality
For ducted systems, leaky or poorly insulated ductwork can significantly reduce efficiency. If ductwork is non-existent or in poor repair, a ductless mini-split system is often the smarter choice.
3. Regional Climate
Heat pumps are naturally efficient in moderate climates. In extreme cold (below 25°F-30°F), standard units may work harder and use more electricity. However, cold climate heat pumps can operate efficiently down to -22°F. In humid climates, high-efficiency models excel at dehumidification by running continuously at variable speeds.
4. Proper Sizing
An undersized unit will run constantly, driving up bills, while an oversized unit will cycle on and off frequently, causing wear and tear. Always have a qualified technician perform a load calculation for proper heat pump installation.
5. Home Insulation
Maximize your system’s performance by:
- Weather stripping doors
- Caulking windows
- Insulating ductwork, walls, and attics
6. Inverter/Variable-Speed Technology
Inverter-driven and variable-speed heat pumps can adjust their heating and cooling output to match the needs of the home. Rather than frequently cycling on and off at full capacity, the system can operate at lower speeds for longer periods, which can reduce energy use during periods of moderate demand. This modulation can improve overall efficiency while also helping maintain more consistent indoor temperatures and comfort.
7. Refrigerant Types: R-454B Transition
R-454B is a lower-global-warming-potential (GWP) refrigerant being adopted in new residential heat pumps as the HVAC industry transitions away from R-410A. Heat pumps using R-454B are designed to deliver efficient heating and cooling while meeting current refrigerant requirements. Because refrigerant type can influence equipment design and efficiency, homeowners replacing an older heat pump should work with a qualified HVAC professional to select equipment that provides the appropriate efficiency for their home.
8. Dual-Fuel/Hybrid Heat Pump Configuration
A dual-fuel, or hybrid, system combines an electric heat pump with a gas furnace to use each heating source when it can operate most efficiently. The heat pump can provide efficient electric heating during milder outdoor temperatures, while the furnace can take over when colder conditions make heat-pump operation less efficient or when supplemental heat is needed. This flexibility of a dual fuel heating system can help optimize energy use and operating costs across a wider range of outdoor temperatures.
Rebates for High Efficiency Heat Pumps
Investing in high efficiency heat pumps often qualifies you for financial incentives that offset upfront costs. Utility companies frequently offer rebates for systems with high SEER2 and HSPF2 ratings. Visit our HVAC Rebates page to see what incentives are available in your area.
Carrier Heat Pump Efficiency
Carrier offers heat pumps across a range of efficiency levels to help homeowners choose a system based on their home’s heating and cooling needs. The table below compares three Carrier heat pump models by SEER2, EER2 and HSPF2 ratings, providing a quick look at their cooling and heating efficiency.
| Model | Tier | SEER2 | EER2 | HSPF2 |
| 27VNA3 | Infinity® 23 Heat Pump | Up to 23 | Up to 13.5 | Up to 10.5 |
| 27VPA9 | Performance™ 19 Heat Pump | Up to 19 | Up to 14 | Up to 10 |
| 27SCA5 | Comfort™ 16 Heat Pump | Up to 16 | Up to 13 | Up to 8.1 |
Need Expert Advice?
Our vast network of dealers can clarify the differences between efficiency ratings and help you find the perfect system. Contact your local Carrier dealer today to start your journey toward a more efficient home.
Frequently Asked Questions
The true efficiency is measured by SEER2 (cooling) and HSPF2 (heating). Unlike gas furnaces which max out at 98% efficiency, heat pumps can achieve 300% to 500% efficiency because they transfer heat rather than creating it from fuel.
Standard heat pumps begin to lose efficiency when temperatures drop below 25°F–30°F. However, modern cold climate heat pumps are engineered to maintain high efficiency and heating capacity even when outdoor temperatures drop as low as -22°F.
Yes. For every 1 unit of electricity a heat pump consumes, it can move 3 units of heat energy into your home. This makes them significantly more efficient than electric resistance heaters, which operate at a 1:1 ratio (100% efficiency).
Replacing a traditional furnace or AC with a high-efficiency heat pump can help reduce energy bills. Exact savings depend on your local utility rates, climate, and the efficiency of the unit you are replacing, but the superior energy transfer capabilities of heat pumps generally lower operational costs.
A SEER2 rating of 14.3 is the federal minimum for split systems, but a rating of 16 or higher is generally considered good. For maximum savings and comfort, look for high efficiency heat pumps with ratings of 17 SEER2 and above.
About The Author: Ryan Mayes is a Senior Digital Brand Marketing Manager at Carrier who focuses on creating clear, helpful resources on HVAC topics. Ryan’s goal is to guide readers toward smart, confident decisions about their indoor comfort.
About The Expert Reviewer: Zach Dickey is a Product Manager for Residential Heat Pumps at Carrier Corporation, where he helps develop innovative heating and cooling solutions that meet homeowners' evolving comfort needs while aligning with industry trends, energy efficiency standards, and regulatory requirements.