About HeatingCodes

HeatingCodes is a reference site for people whose heat just stopped working. When a furnace blinks, a tankless water heater shows an error or a mini-split flashes a code, most search results are thin lists that repeat each other and sometimes mix up brands. We try to do one thing well: tell you what the manufacturer's own document says the code means, link the document, and be clear about which models it covers.

Who runs it

Jason Dearmin, Founder and editor, Washington State, USA.

HeatingCodes is edited by Jason Dearmin in Washington State. Every code meaning on this site is checked against a manufacturer manual or official source that we link on the page.

HeatingCodes is a research and reference site. It is not written by a licensed HVAC contractor and it does not replace one.

What we publish

• Fault code tables for furnaces, tankless and tank water heaters and mini-splits, each tied to a named manufacturer document.
• Guides on winter heating problems, using manufacturers, the U.S. Department of Energy, ENERGY STAR and state health agencies as sources.
• Free tools: a code decoder, a heating cost calculator that uses U.S. Energy Information Administration prices, and a repair-vs-replace calculator.

What we do not do

• We do not tell you how to bypass or defeat a safety switch or sensor.
• We do not publish a code meaning we could not confirm in a source.
• We are not a contractor, we do not sell repair services, and we are not affiliated with any equipment manufacturer.

How the site is paid for

HeatingCodes shows advertising through Google AdSense. Ads never change what we write or which sources we use. See our privacy policy for how advertising cookies work and how to opt out, and our editorial policy for how we check facts and handle corrections.

Corrections and contact

Spotted an error or have a manual we should read? Write to contact@heatingcodes.com. See the contact page.