Questions to ask before you sign an HVAC contract
Equipment brand gets the attention, but sizing and installation decide how the system performs.
Published Oct 23, 2026. 1 min read.
Most HVAC quotes lead with the equipment brand. The installation details are what you should press on.
Was the system sized for your house?
Ask whether a load calculation (often called Manual J) was done, or whether the new unit simply matches the old one's size.
What exactly is being replaced?
Indoor and outdoor units, the refrigerant line set, the thermostat, the electrical disconnect and the condensate drain are each separate items. Ask which are new and which are reused.
Permit and start-up
Ask who pulls the permit and whether the installer will test refrigerant charge and airflow at start-up, and give you the readings.