Signing an HVAC contract without clarifying scope is how change orders and disappointment happen. Before you commit, use these ten questions to pressure-test each bid.
1. What are the exact outdoor and indoor model numbers, capacities, and efficiency ratings?
2. Was equipment size based on a Manual J load calculation—or what rule of thumb was used?
3. Who pulls permits and schedules inspections?
4. What electrical work is included if the panel or disconnect needs upgrading?
5. Are duct modifications, sealing, or replacement included, and how were they evaluated?
6. What thermostat is supplied, and does it support the staging or variable-speed features quoted?
7. How is the old equipment disposed of and the refrigerant recovery handled?
8. What is the payment schedule, and what must be completed before final payment?
9. How are change orders priced if hidden damage or code upgrades appear mid-project?
10. What labor and parts warranties apply, and what registration steps are required?
Also confirm timelines on the start and completion windows of your project, cleanup responsibilities, and whether startup testing—including airflow and temperature split measurements—is part of the scope. Ask whether refrigerant type and line set replacement are included if the new unit uses a different refrigerant than the old system. New A2L Refrigerants and their required equipment are now the standard with older ones (410a and R22) being phased out with equipment no longer being manufactured. Request that answers appear in the written proposal, not only in conversation, so you can compare contractors after site visits.
Strong contractors answer these questions with specifics. Vague responses are a signal to pause. Written side-by-side comparisons often reveal missing scope that lump-sum pricing hides. Keep a simple checklist while you collect bids so nothing falls through the cracks during sales visits. Independent bid review can flag gaps before money changes hands. Want to really be sure you've done everything possible to make a good informed decision? We got your back here at AcBidReview.com and are happy to look your bids over for you, so don't fret. We are here to help with our independent review.