Preferred sources
U.S. Department of Energy, ENERGY STAR, IRS, AHRI, state energy offices, public utility commissions, utilities and manufacturer technical documents are preferred for the claims they directly support.
Product and program records
Use exact model numbers, matched-system references, dated program pages and current terms. Program status and eligibility can change by year, ZIP code, equipment and income.
Source limitations
No source substitutes for a site assessment, local code check, contractor contract or official program confirmation. We link users to primary sources where a decision requires verification.
Last updated: 6 August 2026