Direct answer
Use this checklist to ask how sizing was calculated, what assumptions were used, what the installation requires and what should be verified before purchase.
template
HVAC Contractor Questions
Printable questions to ask an HVAC contractor about sizing method, ducts, airflow, electrical needs, installation and warranty.
Sources and maintained assumptions
Sizing assumptions are centralized and show source URLs, check dates and notes.
- DOE Room Air Conditioners
Checked 2026-05-22. Used for room AC preliminary BTU rule, room-level sizing caveats and oversizing humidity cautions.
- DOE Portable Air Conditioners Test Procedure
Checked 2026-05-22. Used for portable AC SACC / label caveats.
- ENERGY STAR Certified Dehumidifiers
Checked 2026-05-22. Used for pints/day and product rating caveats.
- HVI Bathroom Ventilation
Checked 2026-05-22. Used for residential bathroom fan CFM rules and fixture model.
- ACCA Technical Manuals
Checked 2026-05-22. Used to define Manual J, Manual S and Manual D boundaries.
- EPA Mold and Indoor Air Guidance
Checked 2026-05-22. Used for mold and water intrusion disclaimers.