How to Choose an HVAC Contractor (and Spot the Bad Ones)

Verify the license yourself with your state or local licensing board — don't take a number on a truck at face value. Confirm general liability insurance and workers' comp. In many states, HVAC is licensed at the state level (often as a mechanical or warm-air license); in others it's county or city — either way, the board's website is the source of truth.

Check how long they've operated under the same name, and read reviews looking for patterns rather than individual complaints: recurring mentions of no-shows, upselling, or warranty dodging matter more than one angry review.

A serious bid starts with a Manual J load calculation — the engineering math that sizes your system to your house. Any contractor who sizes by 'rule of thumb' (tons per square foot) or just matches the old unit's size is guessing, and the old unit may have been wrong for decades.

The proposal should be line-itemed: equipment model numbers, labor, ductwork modifications, electrical work, permits, thermostat, and warranty registration. Model numbers matter — 'a 3-ton 16 SEER system' without a model number can mean several different units at different prices.

Same-day-signing pressure and 'this price expires tonight.' Demands for large deposits or full payment upfront — progress payments tied to milestones are normal; 50%+ before work starts is not. A quote given over the phone without visiting. Reluctance to pull permits. And the classic: recommending a full replacement without explaining what specifically failed.

Also watch for the bait-and-switch on efficiency: quoting a high SEER2 rating verbally while the proposal's model number tells a different story. Verify model numbers against manufacturer spec sheets.

Ask: 'Will you do a Manual J, and can I see it?' 'What happens to my ductwork — are you testing it?' 'Who actually does the work — your employees or subcontractors?' 'What does your workmanship warranty cover, and for how long?' 'How do you handle a callback if something's wrong after install?'

Good contractors answer these directly and in writing. Evasive answers are themselves an answer.