Bad HVAC advice on the internet is not a nuisance. It puts people on ladders they should not be on and inside burner compartments they should not open. This page documents exactly how content on Repair or Call is produced, so you can judge whether to trust it.

How we research a guide

Every diagnostic article is built from three kinds of source, in this order of authority:

  • Manufacturer service literature. Installation and service manuals, sequence-of-operation charts, and diagnostic flash-code tables from Carrier, Trane, Lennox, Goodman, Rheem, A.O. Smith, Bradford White and the other major residential brands. Where a fault code or a spec is quoted, it comes from the manual, not from a forum.
  • Codes and standards. The relevant sections of the International Residential Code, NFPA 54 (National Fuel Gas Code), and EPA Section 608 rules for refrigerant handling. We flag where local amendments commonly differ.
  • Published pricing. Cost ranges are compiled from publicly available pricing: parts and equipment list prices, published cost guides and contractor price pages, spanning low-cost and high-cost labor regions. They are estimates to read a quote against, not a quote.

How pricing is calculated

Every figure on this site is an installed price in US dollars, meaning parts plus labor plus the contractor's margin, unless the table says otherwise. We publish a low and a high rather than a single number because the spread between a rural market and a coastal metro is real and hiding it would be dishonest.

Ranges assume normal business hours and a straightforward job. Emergency, after-hours and weekend rates typically run 20% to 40% higher, and we say so where it matters. We do not accept payment from contractors or manufacturers to adjust a published range, and we do not use pricing supplied by lead-generation partners.

Who writes it

Repair or Call is an advice site, not a trade business. The guides are not written or reviewed by a licensed tradesperson, and we do not present them as if they were. Causes are listed in the order the manufacturer literature and common service guidance put them: most likely and cheapest first.

Before an article publishes we check three things: that every fact and figure traces back to a source, that no step instructs a homeowner to do licensed work, and that every safety threshold sits where the codes and manufacturers draw it, never looser.

Safety thresholds

We use one consistent rule. If a task requires breaking a gas connection, opening a sealed refrigerant circuit, working on the line side of a disconnect, or evaluating a heat exchanger, the article says call a pro, regardless of how many videos exist showing otherwise. Articles touching gas or line voltage carry a safety notice above the content, not buried at the bottom.

Updates and corrections

Every article is reviewed at least once a year, and cost tables are re-priced annually against current published pricing. The Updated date in each byline reflects the last substantive review. We do not touch a date to look fresh to a search engine.

Articles are also updated outside that cycle when a code changes, a manufacturer issues a service bulletin, or a reader shows us we got something wrong. Corrections to a material fact are made promptly and, where the correction changes the advice, noted in the text.

If you believe something here is wrong, send a correction. Corrections from working tradespeople go to the front of the queue.

Independence from advertising

Repair or Call is funded by display advertising, contractor referral fees, and affiliate commissions. Editorial decisions are made without reference to any of it. Advertisers do not see content before publication, cannot request changes, and cannot buy a mention. Products named in an article are named on their merits.

On generative AI

AI tools may be used for outlining, formatting and copy editing. They are not used to generate diagnostic sequences, safety guidance or price ranges, and no article publishes without a human editor having read it end to end and checked it against its sources.