About HVAC Cheat Sheet

HVAC Cheat Sheet is a free field reference for heating and air conditioning techs: the calculators, numbers and explanations you'd otherwise dig through manuals, apps and forums to find. Everything works in a phone browser with no login.

Who's behind it

HVAC Cheat Sheet is published by 90 Leads, a marketing company that works with home service businesses, including HVAC contractors.

How we check our work

• Every calculator shows the formula it uses, right under the tool.
• Formulas come from standard industry references and are tested against known values before they go live.
• Technical articles are reviewed by an experienced HVAC technician and show when they were last reviewed.

This site is a reference, not a substitute for training, the manufacturer's instructions or local code. If something looks wrong, email hello@hvaccheatsheet.com and we'll fix it.