Questions to Ask Your HVAC Contractor Before Signing

Licensing and Insurance Questions

"Are you licensed for HVAC work in this jurisdiction, and can I see the license?" Every state requires some form of contractor licensing for HVAC work, though the specific requirements vary. A legitimate contractor will have their license number readily available and will not hesitate to show it. You can verify the license status through your state's contractor licensing board website. An unlicensed contractor exposes you to liability if something goes wrong and may not be able to pull the permits required for the work.

"Do you carry general liability insurance and workers' compensation?" General liability insurance protects you if the contractor damages your property during the installation. Workers' compensation protects you from liability if a worker is injured on your property. Ask to see certificates of insurance, not just a verbal confirmation. A contractor without adequate insurance leaves you financially exposed to property damage and injury claims.

Sizing and Design Questions

"Will you perform a Manual J load calculation to size the system?" This is the single most important technical question. A proper load calculation determines the exact heating and cooling capacity your home needs based on its specific characteristics. A contractor who sizes the system based on the old system's size, a square-footage rule of thumb, or "experience" is guessing. The consequences of wrong sizing are serious: an oversized system short-cycles, wastes energy, and fails to dehumidify; an undersized system runs constantly and cannot maintain comfort during extreme weather. Our Manual J guide explains why this matters.

"What did you find when you inspected the ductwork?" A contractor who did not inspect the ductwork cannot give you an accurate quote. The ductwork condition, sizing, and sealing directly affect system performance and may require additional work that changes the project cost. If the contractor did not look at the ducts, they are either planning to quote without full information (leading to change orders) or they do not understand the relationship between ductwork and system performance.

Equipment and Technology Questions

"What specific equipment models are you proposing, and why?" The contractor should name exact model numbers and explain why those models are the right fit for your home. The explanation should reference the load calculation results, your comfort priorities, and the value proposition at the proposed efficiency level. A contractor who cannot explain why they chose specific equipment is either selling what they have in stock or pushing whatever earns them the highest margin.

"What refrigerant does this system use?" In 2026, the answer should be R-454B for new equipment. If a contractor proposes an R-410A system, ask where it comes from and whether it was manufactured before the January 2025 cutoff. There is nothing wrong with installing remaining R-410A inventory that was manufactured before the deadline, but you should understand that future service will use reclaimed refrigerant and that R-454B is the forward-looking standard.

"What SEER2 rating is this system, and what would the next step up cost?" Understanding the cost and savings difference between efficiency levels helps you make an informed decision. A good contractor will explain the payback calculation and help you choose the efficiency level that makes financial sense for your situation rather than simply pushing the most expensive option. Our SEER rating guide provides the context to evaluate their answer.

Warranty and Service Questions

"What is the manufacturer warranty, and what is your labor warranty?" These are two separate things, and both matter. The manufacturer warranty covers parts (typically 10 years if registered). The contractor's labor warranty covers the cost of service calls to diagnose and fix problems with the installation itself. A 1-year labor warranty means you pay for any installation-related problems that appear after 12 months. A 5 to 10 year labor warranty means the contractor stands behind their work for a meaningful period. The difference in quality contractors often shows in the labor warranty they are willing to offer.

"Who will register the manufacturer warranty?" Most manufacturer warranties require registration within 60 to 90 days of installation to receive the full 10-year coverage. Without registration, the warranty typically drops to 5 years. The contractor should handle this registration as part of the project. Ask for confirmation that it has been completed after the installation.

"What happens if something goes wrong after hours?" Air conditioning failures do not respect business hours. Ask whether the contractor offers emergency or after-hours service, what the response time typically is, and whether there is an additional charge for after-hours calls. A contractor who provides 24/7 emergency service is more useful long-term than one who is only available Monday through Friday.

Timeline and Logistics Questions

"When can you schedule the installation, and how long will it take?" The answer tells you about the contractor's current workload and their assessment of your project's complexity. A one-day estimate for a straightforward change-out is normal. If they estimate two or three days, ask what specifically requires the additional time, this may reveal ductwork or electrical issues that should be reflected in the scope and pricing.

"Who will be doing the actual installation?" Some contractors use their own employees, while others subcontract the installation to independent crews. Neither approach is inherently better, but you should know who will be in your home. Ask whether the installing crew is experienced with the specific equipment being installed and whether a supervisor or project manager will oversee the work.

"Will you pull the permit and schedule the inspection?" The answer should be an unequivocal yes. If the contractor hesitates, offers to skip the permit, or suggests that you pull it yourself, that is a significant red flag. Our permit guide explains why permits are non-negotiable.

Cost and Payment Questions

"Is this quote a firm price, or are there potential additional charges?" Ask the contractor to identify any foreseeable additional costs that are not included in the quoted price. A thorough contractor who inspected the system, ductwork, and electrical will be able to list specific contingencies (if they exist) and provide cost ranges for each. A contractor who says "no additional charges" without having inspected the ductwork and electrical is either cutting corners on the assessment or will surprise you with change orders during installation.

"What payment terms do you require?" Standard practice is a deposit of 10% to 30% at contract signing, with the balance due upon completion and satisfactory testing. Be cautious of contractors who demand full payment upfront or a deposit exceeding 50%. You want to retain enough unpaid balance to have leverage if the installation is not completed satisfactorily.

"Do you offer financing, and what are the terms?" If you need financing, compare the contractor's financing options against your own sources (credit union personal loans, home equity lines, etc.). Our financing guide covers the most common options and their true costs.