I have hired hvac companies for three different houses. I have also watched friends get burned by the wrong ones. This guide is what I wish someone had told me.
Licensing & Insurance Questions
Ask for their license number on the phone before they even come out. Every state has a database where you can check if it is valid and if there are complaints. Do not skip this. Also ask for proof of general liability insurance and workers comp. If a tech gets hurt on your property and the company does not have comp, you pay the medical bills. I have seen that happen. They should email you a certificate of insurance without any attitude.
Experience & References Questions
Ask how long they have been in business. A company that has been around five years usually has stable office staff and established relationships with suppliers. Then ask for at least two recent references from jobs similar to yours. Call those people. Ask them if the crew showed up on time, if they cleaned up every day, and if any surprise costs appeared. People love to complain, so if nobody complains, that is a good sign.
Pricing & Timeline Questions
Never accept a quote over the phone without a site visit. Any company that gives a price sight unseen is guessing, and you will pay for that guess later. Ask for a written estimate that breaks down equipment, labor, and permits. Also ask how long the job will take and what happens if it runs longer. Some companies pad timelines to cover their butts, but a straight answer about schedule tells you a lot.
Contract Questions
Read the contract before you sign. Look for the warranty terms on both the equipment and the labor. Equipment warranty is usually from the manufacturer. Labor warranty is from the company, and that matters more because installation mistakes cause most problems. Also check if they handle permits and final inspection. If they skip permits, your insurance can deny a fire or flood claim later. Find that in the contract before you pay a dime.
Take these questions and compare the answers you get from local hvac companies on RatingsNearMe.