How Pages Are Checked
Pages on The Second Bid are checked against federal rules and agency criteria first, makers' own documents second, with a date on every money or rule figure.
Updated
Which sources come first
Federal rules and agency criteria come first. That means the Code of Federal Regulations and Federal Register for efficiency standards and refrigerant rules, IRS pages for tax credits, DOE program notices for rebates, ENERGY STAR criteria, and EPA, CPSC and CDC pages for safety. Building-code text such as IRC M1401.3 and the ACCA manuals that codes point to sit in the same tier.
Makers' documents come next: installation manuals, warranty pages and spec sheets from equipment makers. They are used for what that maker says about its own products, and they are named as the maker's claim, not as a general rule. Where two sources disagree, the page follows the newer rule or the primary text and says so.
Every outside source is opened before it is cited. Links go to the page that holds the sentence relied on, not to a summary of it.
How dates work
Money and rule figures carry a date, written as "as of October 2026" or with the source's own date. Tax credits, rebate programs, efficiency minimums and refrigerant deadlines all changed between 2023 and 2026, so an undated figure is a risk. When a source is older, such as a 2009 ENERGY STAR booklet, its year is shown beside it.
Each page also shows when it was last updated.
What is left out
Some things are left out on purpose:
- Cost ranges for installs or repairs, because no primary source publishes them and local prices vary widely.
- Forum anecdotes and stories from unnamed homeowners.
- Contractor blogs, lead-generation sites and other secondary summaries.
- Repair steps that belong to a licensed technician, such as anything involving refrigerant, gas valves, burners or capacitors.
Nothing on this site was installed, measured or tested by its publisher. Pages explain what the sources say and what to ask the person doing the work.
Corrections
Pages are re-checked when a rule or program changes, and the update date moves when they are. If a federal rule, program notice or maker's warranty term changes after a page was written, the source it links is the place to confirm the current wording.