Federal Tax Credits for Residential HVAC System Upgrades
The Inflation Reduction Act of 2022 restructured the federal tax credit landscape for residential HVAC upgrades, creating new annual credit ceilings and expanded equipment eligibility that apply through 2032. This page covers how the Energy Efficient Home Improvement Credit (Section 25C) and the Residential Clean Energy Credit (Section 48D for residential) work, which equipment categories qualify, and where the classification boundaries fall. Understanding these distinctions matters because misclassifying equipment type or installation year can result in credits being denied or reduced during IRS review.
Definition and scope
The Energy Efficient Home Improvement Credit, governed by Internal Revenue Code Section 25C as amended by the Inflation Reduction Act (Public Law 117-169), provides a nonrefundable tax credit equal to rates that vary by region of the cost of qualifying HVAC equipment and installation, subject to annual per-category caps. The credit applies to existing primary residences located in the United States — it does not apply to new construction or rental properties.
The Residential Clean Energy Credit under IRC Section 25D covers geothermal heat pumps specifically, at a rates that vary by region credit rate with no annual dollar cap, making it structurally distinct from the 25C credit. For geothermal systems, see the Geothermal HVAC Systems reference for equipment classification detail.
The Department of Energy (DOE) and the Internal Revenue Service (IRS) jointly define qualifying efficiency thresholds. The Consortium for Energy Efficiency (CEE) publishes the Tier designations that IRS references for some product categories. Equipment must meet minimum efficiency standards as defined in IRS Notice 2023-29 and related guidance to be credit-eligible.
How it works
Credits under 25C are calculated annually, meaning the amounts that vary by jurisdiction aggregate cap and the amounts that vary by jurisdiction heat pump sub-cap reset each tax year. The credit is nonrefundable — it reduces tax liability to zero but does not generate a refund.
Annual credit structure (per IRS 25C guidance):
- General cap: rates that vary by region of qualifying costs, up to amounts that vary by jurisdiction per year for most HVAC categories (central air conditioners, furnaces, boilers)
- Heat pump sub-cap: Up to amounts that vary by jurisdiction per year for qualifying heat pumps and heat pump water heaters — this sub-cap is separate from and additive to the amounts that vary by jurisdiction general cap
- Home energy audits: Up to amounts that vary by jurisdiction per year credit for a qualifying audit performed by a certified auditor, which may inform HVAC upgrade decisions
- No lifetime cap: Unlike the predecessor credit (the non-business energy property credit before 2023), there is no lifetime aggregate ceiling
Qualifying efficiency thresholds as of the 2023 IRS guidance include:
- Central air conditioners: SEER2 ≥ 16 (split systems); SEER2 ≥ 15.2 (packaged units) — see HVAC SEER Ratings Explained for how SEER2 differs from legacy SEER
- Gas furnaces: AFUE ≥ rates that vary by region (applicable in northern climate zones per DOE regional standards)
- Heat pumps: Must meet CEE Tier requirements as adopted by IRS; HSPF2 ≥ 7.5 and EER2 ≥ 10 for most configurations
- Boilers: AFUE ≥ rates that vary by region
The credit is claimed using IRS Form 5695 (Residential Energy Credits). Taxpayers must retain the manufacturer's certification statement confirming the equipment meets IRS efficiency thresholds; this document is not filed with the return but must be available if the IRS requests it.
Common scenarios
Scenario 1 — Heat pump replacement in an existing home
A homeowner replaces a central air conditioner and gas furnace with a qualifying air-source heat pump. If the heat pump meets CEE Tier 2 requirements, the homeowner may claim up to amounts that vary by jurisdiction under the heat pump sub-cap. Because a heat pump replaces two legacy forced-air heating systems components simultaneously, the installation cost basis can include both the equipment and labor directly attributable to the HVAC installation.
Scenario 2 — High-efficiency gas furnace upgrade
A homeowner installs a rates that vary by region AFUE gas furnace. The rates that vary by region credit applies to equipment and installation costs up to the amounts that vary by jurisdiction general annual cap. If the same taxpayer also installs qualifying insulation, the amounts that vary by jurisdiction cap covers both — they share the annual ceiling.
Scenario 3 — Ductless mini-split system
A qualifying mini-split ductless HVAC system meeting heat pump efficiency thresholds falls under the amounts that vary by jurisdiction heat pump sub-cap, not the amounts that vary by jurisdiction general cap, because it functions as a heat pump. This distinction is equipment-function-based, not brand- or configuration-based.
Scenario 4 — Geothermal heat pump
A geothermal ground-source heat pump qualifies under IRC Section 25D (not 25C), carries a rates that vary by region credit with no dollar cap, and applies to both primary and secondary residences. The credit is available through 2032 under the Inflation Reduction Act schedule.
Decision boundaries
The following classification boundaries determine which credit category applies and whether a credit is available at all:
| Equipment type | Applicable credit | Annual cap | Efficiency threshold |
|---|---|---|---|
| Central air conditioner | 25C | amounts that vary by jurisdiction (shared) | SEER2 ≥ 16 (split) |
| Gas/propane furnace | 25C | amounts that vary by jurisdiction (shared) | AFUE ≥ rates that vary by region |
| Oil furnace/boiler | 25C | amounts that vary by jurisdiction (shared) | AFUE ≥ rates that vary by region |
| Air-source heat pump | 25C | amounts that vary by jurisdiction (separate) | CEE Tier 2 |
| Geothermal heat pump | 25D | No cap | EER ≥ 17 (DOE) |
Key distinction — 25C vs. 25D: The 25C credit covers most HVAC upgrades but carries annual caps and applies only to existing primary residences. The 25D credit covers geothermal heat pumps and solar-integrated systems, carries no annual cap, and applies to primary and secondary residences. These credits can be claimed in the same tax year if the homeowner installs qualifying equipment under both categories.
New construction exclusion: Neither 25C nor 25D applies to HVAC system for new construction installations. The residence must be an existing home placed in service before the equipment installation date.
Permitting and inspection: IRS guidance does not explicitly require a local permit as a condition of the credit, but HVAC system permits and codes compliance is required by local jurisdictions regardless of federal credit eligibility. Unpermitted installations may face inspection issues that indirectly affect system certification documentation.
Labor costs: Under 25C, qualified installation labor is included in the credit basis for heat pumps and heat pump water heaters. For non-heat-pump HVAC equipment under 25C, IRS guidance specifies that only the property cost (not labor) is creditable — a distinction that materially affects the credit calculation for high-labor installations such as central air conditioning systems replacements involving ductwork modifications.