Editorial policy

Sourcing hierarchy

Tier 1: DOE and the Federal Register, EPA, IRS, ENERGY STAR, state energy offices and public utility commissions, state licensing boards, ICC/IRC/IECC.

Tier 2: ACCA (Manual J/S/D), ASHRAE, AHRI, manufacturer engineering and installation documentation, utility program administrators.

Tier 3 (estimates only, always attributed as such): cost guides, contractor blogs, equipment retailer content.

Contractor and retailer content is the dominant source in this vertical and carries a direct incentive toward larger equipment, higher tiers and faster replacement. It is never the source for a sizing, refrigerant, or “you need to replace” claim.

Risk tiers

R3 legal/regulatory requires a primary source and a dated Jurisdiction Notice. R2 safety/performance requires an ACCA, ASHRAE, AHRI, manufacturer or code citation. R1 general covers costs and comparisons.

Safety verdicts

Every page touching a physical action carries a verdict. See the full policy.

Freshness

Pages marked volatile are re-verified every 90 days. See the freshness policy.

Corrections

We correct errors on the page itself and note the change. Write to [email protected].

AI use

We use assistive tooling for research and drafting. No regulatory figure is published unless a person has read it at the primary source and recorded the verification date in our sourcing log.