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Homeowner pre-check

Need a Manual J Calculation? First Check What Your Project Actually Requires

See whether your quote shows a real sizing basis, what a formal Manual J would still need, and when a pre-check is enough.

Check My Manual J Readiness See Pricing

Pre-check only

HVACPreCheck provides informational pre-check reports only. We are not a licensed HVAC contractor, engineer, tax advisor, or permit authority. Our reports are not stamped engineering documents and do not guarantee permit approval, equipment sizing, rebate eligibility, tax credit eligibility, energy savings, or comfort outcomes. Always confirm requirements with your contractor, local building department, utility, tax professional, or licensed engineer.

What this page helps you check

  • What a Manual J can and cannot tell you
  • Signs your quote may be missing a real sizing basis
  • Which project details a formal calculation would require
  • When to stop at a pre-check and when to escalate

Readiness signals

  • Quoted tonnage with no load assumptions is a red flag
  • Missing equipment models makes rebate and match review harder
  • No duct note means comfort risk may still be unresolved

Questions to ask your contractor

  1. What sizing method supports the quoted tonnage?
  2. Did you inspect duct condition, insulation, and windows?
  3. If the city asks for load documentation, who provides it?
  4. What assumptions would change the equipment recommendation?