Quick take
- A good contractor sizes the system from your home’s details, not a rule of thumb.
- New split central ACs installed in the DOE’s Southeast region since Jan. 1, 2023, must be at least 14.3 SEER2 (13.8 SEER2 for larger units).
- Ask how they’ll check airflow, refrigerant charge and duct leaks, and get it in writing.
- Check the contractor’s state license. In Louisiana, for example, jobs of $7,500 or more on an existing home need an LSLBC registration.
In hot, humid summers, the air conditioner is the hardest-working system in the house. Replacing one costs a lot, and a poor installation can waste energy for years. Here’s how to compare HVAC contractors and bids.
This guide is general information, not legal advice. Licensing rules and dollar limits differ by state and can change. Check with your state’s contractor licensing board for your exact project.
1. Check the license first
Each state sets its own licensing rules. In Louisiana, for example, the Louisiana State Licensing Board for Contractors (LSLBC) requires a home improvement registration for work of $7,500 or more (labor and materials) on an existing home. Projects over $50,000 need a residential license. Look up any company free at the LSLBC Contractor Search. Make sure the company name on your bid matches the license record.
Under Section 608 of the Clean Air Act, technicians who maintain, service, repair or dispose of equipment that could release refrigerant must be EPA-certified. (Apprentices working under a certified technician are an exception.) It’s fair to ask whether the crew installing your system is certified.
The LSLBC also lists mechanical work over $10,000 (labor and materials) among the jobs that need a license with that classification on commercial projects. For work on your home, the thresholds above are what the board lists. If you’re not sure which license your job needs, ask the LSLBC.
2. Know the efficiency minimums
Federal efficiency standards changed on Jan. 1, 2023. The U.S. Department of Energy’s Southeast region covers much of the South, including Louisiana, Texas, Arkansas and Oklahoma. It has higher minimums for central air conditioners. According to the DOE’s FAQ on the 2023 standards:
| System | Southeast minimum |
|---|---|
| Split central AC, under 45,000 Btu/h (installed on or after Jan. 1, 2023) | 14.3 SEER2 |
| Split central AC, 45,000 Btu/h and up (installed on or after Jan. 1, 2023) | 13.8 SEER2 |
| Split heat pump, nationwide (made on or after Jan. 1, 2023) | 14.3 SEER2 / 7.5 HSPF2 |
For central ACs in the Southeast, the rule depends on the installation date. For heat pumps, the national rule depends on the manufacture date. A bid can offer more efficient equipment than the minimum. Ask the contractor what the higher rating would save you each year and what it costs up front.
3. Insist on proper sizing
ENERGY STAR says your contractor should use your home’s actual characteristics to size the equipment, and not just rely on a “rule of thumb.” Equipment that’s too big may turn on and off too often. That means less comfort and a shorter life for the system. Ask the contractor how they sized your system, and ask for the calculation.
4. Ask what the installation includes
ENERGY STAR recommends a contractor who will:
- Check and adjust airflow. Poor airflow can mean higher bills, damp air and a shorter equipment life.
- Test and adjust the refrigerant charge.
- Inspect the ducts and fix leaks, which waste energy and reduce airflow.
ENERGY STAR also has a free bid comparison sheet you can use to compare quotes side by side. Ask each contractor to put these steps in writing.
5. Compare bids
- Get at least two or three written bids.
- Compare equipment model numbers, efficiency ratings, warranty terms and what’s included, not just the price.
- Get a complete written contract, and don’t pay the full amount up front. See our contractor hiring guide for contract basics.
Before the first cold night, see our fall home checklist for filter changes and heat tests.