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Contact

Get in touch.

The fastest way to reach us is email. Real people read every message, usually within two business days.

Email

[email protected]

Drop us a line for anything: a calculator that returned a weird number, a code citation you want us to double-check, a tool we should add, a typo, a broken link, or a tradesperson tip we should fold into the methodology. Field feedback from licensed techs makes these tools better. We will reply.

What to include if you are reporting a bug

If a calculator returned something that does not match a manufacturer engineering data sheet, a published code section, or a result you got from paid software, include the following so we can reproduce it.

  • The specific calculator URL (for example /calculators/subcooling/)
  • The exact input values you used
  • The result the calculator gave you
  • The reference you are comparing against (manufacturer sheet, code section, alternate calculator, your meter readings)
  • Your browser and device, if the issue looks like a display problem rather than a math problem

Press, partnerships, technical collaboration

Same email works. Mention "press" or "partnership" in the subject line and the right person will see it sooner. We are open to citation requests from trade publications, link partnerships with HVAC training programs, and collaboration with manufacturers who want their data referenced accurately.

What we cannot help with

We do not diagnose specific HVAC problems by email. If your system is not cooling, the compressor is short-cycling, or a breaker keeps tripping, that needs a licensed tech on site with a manifold and a meter. The calculators on this site help you understand the math and check a contractor's work. They do not replace one.

We also cannot provide contractor recommendations, quote specific equipment for your house, or interpret your local code inspector's call. Those are jobs for your local ACCA-certified contractor or your AHJ.