Contracts and quotes
Questions to ask an HVAC installer before you sign
Ask for the TDLR license number, how the system was sized, the exact model numbers and refrigerant, what the price includes, who pulls the permit, what the labor warranty covers and who registers the equipment, and the payment schedule. Ask every installer the same questions and get the answers written on the quote.
On this page (15)
- Why the questions matter more than the brand
- 1. License, insurance and registration
- 2. How the system was sized
- 3. The equipment itself
- 4. What the price includes
- 5. Permit and inspection
- 6. Labor warranty and equipment registration
- 7. Price, payment and paperwork
- 8. The installation day
- Answers worth questioning
- Worked example: two quotes, same size
- Common mistakes when interviewing installers
- The short list to take to the home visit
- Sources
- Questions
Why the questions matter more than the brand
ENERGY STAR material states that nearly half of heating and cooling equipment in US homes never performs to its advertised capacity and efficiency because of installation problems. In other words, the same equipment can perform well or poorly depending on how it is sized, set up and connected to the ducts. The brand on the outdoor unit tells you little about that. The installer's answers tell you a lot.
Questions also make quotes comparable. Two bids for a "3-ton system" can differ by thousands of dollars because one includes a new coil, line set, drain work and the permit, and the other does not. The questions below pull those differences into the open before you sign.
Use this list at the home visit, not over the phone. A contractor who has not seen the attic, the ducts and the electrical panel cannot answer most of it. When you have two or three written quotes, put them side by side in the quote comparison tool.
How to use this guide
Pick the questions that apply to your job, ask each installer the same ones, and write the answers on the quote or ask for them by email. A verbal answer you cannot point to later is worth much less than a written one.
1. License, insurance and registration
Start here, because everything else depends on it. The Texas Department of Licensing and Regulation (TDLR) licenses air conditioning and refrigeration (ACR) contractors, and ACR companies must employ a licensed ACR contractor at each permanent location. Home comfort systems fall under the Environmental Air Conditioning endorsement: treating air to control temperature, humidity, cleanliness, ventilation and circulation for human comfort. Commercial Refrigeration and Process Cooling or Heating are separate endorsements.
A Class A license allows work on any size unit. A Class B license allows work on cooling systems of 25 tons and under and heating systems of 1.5 million Btu/hour and under. Either class covers a typical house. What matters is that the license is active and belongs to the company named on your contract.
- What is your TDLR license number, and which license holder is assigned to this company?
- Is the license active, and does it carry the Environmental Air Conditioning endorsement?
- Can you email me your certificate of liability insurance?
- Are you registered with my city to pull mechanical permits?
- Will your own employees do the work, or a subcontractor? If a subcontractor, what is their license number?
At all times during the license period, a Class A contractor must carry commercial general liability insurance of at least $300,000 per occurrence, $600,000 aggregate and $300,000 products and completed operations; a Class B contractor at least $100,000, $200,000 and $100,000. You can ask for the certificate and check the dates. The TDLR license search takes a license type, license number, name (Last, First, or the business name), city, county or ZIP. It covers active licenses only, so "no result" can mean a license has expired.
The Texas HVAC license check walks through the lookup and how to read the record.
2. How the system was sized
Sizing is where installations most often go wrong, and it is easy to ask about. ACCA Manual J (ANSI/ACCA 2, 8th edition) is the American National Standard for residential heating and cooling load calculation. Dallas enforces the 2021 International Residential Code and 2021 IECC with Dallas amendments, effective 12 May 2023. The IRC requires equipment to be sized from a load calculation (ACCA Manual J) rather than a rule of thumb.
A load calculation looks at the house as it is: square footage, insulation, windows and their direction, air leakage, duct location and the local design temperature. A rule of thumb such as "one ton per so many square feet," or "same size as the old one," skips all of that.
- How did you size this system? Did you run a load calculation, and can I have a copy of the summary?
- What cooling load did the calculation give, in BTU per hour?
- Why is your recommended size different from another quote I have?
- Did you go into the attic and look at the ducts? Did you account for them in the size?
- If I seal ducts or add insulation, would that change the size you recommend?
Why oversizing is not "safe"
A system that is too large cools the air quickly and shuts off before it has run long enough to pull much moisture out. The house can feel cold and clammy, and the equipment cycles on and off more often. See problems with an oversized AC and what size AC a Dallas home needs.
3. The equipment itself
Ask for complete model numbers for every piece, not just the brand and size. A central split system is at least two matched parts: the outdoor condenser and the indoor coil, plus a furnace or air handler that moves the air. The rated efficiency applies to the combination, which is why the match matters.
Texas is in the DOE Southeast region. Since 1 January 2023 a split-system central AC under 45,000 BTU (about 3.75 tons) must be at least 14.3 SEER2 on the date it is installed; larger systems need 13.8. Split heat pumps need 14.3 SEER2 and 7.5 HSPF2 nationwide.
Equipment made or imported since 1 January 2025 uses lower-GWP A2L refrigerants (R-454B or R-32) instead of R-410A. An EPA rule finalized in May 2026, effective 27 July 2026, removed the 1 January 2026 cutoff, so contractors may install pre-2025 R-410A systems until that stock runs out. See R-410A versus the new refrigerants for what that means for a quote.
- What are the full model numbers for the outdoor unit, indoor coil and furnace or air handler?
- Is this an AHRI-matched combination, and what is the AHRI reference number?
- What are the SEER2 rating and, for a heat pump, the HSPF2 rating of this combination?
- Which refrigerant does it use: R-410A, R-454B or R-32? If R-410A, when was it made?
- Are you replacing the indoor coil, or reusing the old one?
- Is the equipment single-stage, two-stage or variable speed, and why did you pick that for my house?
If a quote lists only "3-ton 15 SEER2 system," ask for the model numbers before comparing it with anything. Without them you cannot check the rating, the refrigerant or the warranty.
4. What the price includes
Most of the gap between quotes is scope, not margin. Go item by item and ask whether it is included, excluded, or "if needed" at an extra price. An "if needed" item should carry a price on the quote, so you are not negotiating it with the system already half installed.
| Item | Question to ask | Why it matters |
|---|---|---|
| Indoor coil | New coil, or reusing the old one? | A mismatched coil can affect the rated efficiency and the warranty. |
| Line set | New refrigerant lines, or flushing and reusing? | Refrigerant changes and old lines are a common source of later problems. |
| Condensate drain | New drain line, pan, float switch? | A blocked drain in an attic unit can leak through the ceiling. |
| Pad and disconnect | New pad, electrical disconnect and whip? | Old parts are often reused unless the quote says otherwise. |
| Thermostat | Included? Which model? | Some systems need a compatible thermostat to run as designed. |
| Ducts | Inspect, seal, repair or replace? Any test? | Leaky ducts waste cooling before it reaches the rooms. |
| Electrical | Breaker, wiring or panel changes needed? | Panel work is priced separately and can be large. |
| Permit and inspection | Who applies, and is the fee in the price? | Most DFW cities require one for a replacement. |
| Haul-away | Old equipment removed and refrigerant recovered? | Refrigerant handling is regulated; ask who does it. |
ENERGY STAR estimates that about 20 to 30 percent of the air moving through a typical duct system is lost to leaks, holes and poorly connected ducts. That is why the duct question deserves a real answer. Ductwork sealing and replacement explains the options and published Dallas prices.
5. Permit and inspection
Several DFW cities state on their own pages that replacing an AC unit needs a mechanical permit. Garland says permits are required for replacement of air-conditioning units; Carrollton says a permit is needed when any part of the indoor or outdoor unit is repaired or replaced. In the City of Dallas, permits go through the DallasNow portal.
The permit matters to you because it brings an inspection by the city, a record tied to your address, and a check that the work meets the adopted code. In most cities the licensed contractor applies.
- Will you pull the permit, and is the fee included in this price?
- Which city or county office issues it for my address?
- Who schedules the inspection, and do I need to be home?
- Will you give me the permit number and the final inspection result?
Answer to question
"You don't need a permit for a change-out" contradicts what several DFW cities publish. Ask the contractor to name the city rule, then check the Dallas-area permit guide for your address.
6. Labor warranty and equipment registration
There are usually two warranties. The manufacturer covers parts; the installer covers their own labor and workmanship. They have different terms and different people to call, so ask about both.
Registration can change the parts warranty. Trane extends its warranty term only if the product is registered within 60 days of installation; registered late, it keeps the base warranty. Lennox requires registration within 60 days of installation (or closing, for new construction) for its extended limited warranty. Other manufacturers have their own rules, so ask which applies to the brand you are buying.
- How long is your labor warranty, and what does it cover and exclude?
- Is the labor warranty in writing on the contract or a separate document?
- Who registers the equipment with the manufacturer, and by what date?
- Will I get a copy of the registration confirmation?
- Does the manufacturer warranty require maintenance records, and does your company offer a maintenance plan? Is it optional?
The AC warranty guide covers parts, labor and registration in more detail.
7. Price, payment and paperwork
For context, published DFW ranges for replacing a 3-ton AC on existing ducts run $5,500–$16,500. These are third-party published ranges, not this site's prices, and your quote may sit anywhere in or outside them depending on scope. See the Dallas AC installation cost guide for the sources.
Texas rules set what the paperwork must show. The licensee’s number must appear on all advertising, proposals and invoices, an invoice is required for all ACR work, and proposals, invoices and written contracts must carry the notice “Regulated by The Texas Department of Licensing and Regulation, P.O. Box 12157, Austin, Texas 78711, 1-800-803-9202, 512-463-6599; www.tdlr.texas.gov”.
In Texas, labor to repair or remodel residential property is not taxable; the materials are. Your invoice can be lump-sum (tax built into the contractor's material cost) or separated (tax shown on the materials line). Both are normal.
- What deposit do you take, and when is the balance due?
- Is the final payment due after the system is running and the permit inspection has passed?
- Is this price fixed, or can it change? If it can, what would change it?
- Does the proposal show your TDLR license number and the TDLR consumer notice?
- If you offer financing, what are the rate, term and total cost, in writing?
Three-day cancellation
Under Texas Business and Commerce Code §601.051, a consumer may cancel a consumer transaction until midnight of the third business day after signing, where the sale was solicited and agreed somewhere other than the merchant’s place of business and the price is over $25. Ask whether it applies to your contract, and read the contract checklist before signing.
8. The installation day
Practical questions save surprises. A like-for-like replacement is often done in about a day, but larger scope adds time. What happens during AC replacement explains the sequence.
- How long will the job take, and when will cooling be off?
- Do you need access to the attic, garage, closet and breaker panel?
- How will you protect floors and the attic insulation?
- Will you test the system before you leave? What readings do you record, and can I have them?
- Who is the contact if something is wrong after you leave?
Answers worth questioning
Some answers are not wrong on their own, but they deserve a follow-up question. Use this table to decide which.
| What you hear | Why to push back | Follow-up |
|---|---|---|
| "Same size as the old one." | The old unit may have been the wrong size, and the house may have changed. | Can you run a load calculation and show me the result? |
| "You don't need a permit for a change-out." | Several DFW cities state that replacement needs one. | Which city rule says that for my address? |
| "We'll register it if you want." | Registration can decide the warranty term. | Please register it and send me the confirmation. |
| A firm price over the phone | Nobody has seen the ducts, panel or attic. | Can you visit before quoting? |
| "It's a 16 SEER system" with no model numbers | You cannot check the rating or match. | What are the model numbers and AHRI reference? |
| "Your ducts are fine" without going into the attic | Ducts cannot be judged from the hallway. | Did you inspect them? Would you test for leakage? |
| "Sign today for this price" | A real price does not usually expire overnight. | How long is this quote valid, in writing? |
Worked example: two quotes, same size
Say a 1990s two-story home in Richardson gets two quotes for a 3-ton central AC. Quote A is lower. Quote B is higher. On the surface the second looks overpriced.
The questions change the picture. Quote A reuses the indoor coil and line set, excludes the permit fee, and lists duct sealing as "if needed" with no price. Quote B includes a matched coil, a new line set, a new drain pan and float switch, the permit and inspection, and a duct leakage check. It also names the AHRI reference and says the installer will register the warranty.
Quote A
- Reuses coil and lines
- Permit fee extra
- Duct work "if needed", unpriced
- No AHRI reference
Quote B
- Matched coil, new lines
- Permit and inspection included
- Duct leakage check
- AHRI reference, registration included
Once the missing items in Quote A are priced, the gap narrows or disappears. This is a hypothetical example, but the pattern is the reason to ask the same questions of everyone: you end up comparing the same job.
Common mistakes when interviewing installers
- Asking different questions of each installer. The answers will not compare. Use one list.
- Accepting verbal answers. Ask for the key ones in writing on the quote.
- Comparing on SEER2 alone. Installation quality and duct condition can matter as much as the rating.
- Skipping the license check. It takes a minute on the TDLR site.
- Paying most of the price up front. Tie the balance to a working system and a passed inspection.
- Counting on the 25C credit. The federal Energy Efficient Home Improvement Credit (25C) applied to qualifying property placed in service before 31 December 2025. It is not available for a system installed in 2026.
The short list to take to the home visit
- License number, insurance certificate, city registration.
- Load calculation: method, result and a copy.
- Full model numbers, AHRI reference, SEER2/HSPF2, refrigerant.
- Scope: coil, lines, drain, pad, thermostat, ducts, electrical, haul-away.
- Permit: who applies, fee included, inspection result.
- Labor warranty in writing; who registers the equipment and by when.
- Deposit, balance timing, quote validity, license number and TDLR notice on the proposal.
After the job, use the after-installation checklist to confirm you got what was quoted.
Sources
- TDLR license search (retrieved 2026-10-20)
- TDLR, ACR program (retrieved 2026-10-20)
- TDLR, ACR contractor license (classes and endorsements) (retrieved 2026-10-20)
- 16 Tex. Admin. Code §75.40 (retrieved 2026-10-20)
- 16 Tex. Admin. Code §75.71 (Cornell LII mirror) (retrieved 2026-10-20)
- ENERGY STAR HVAC fact sheet (retrieved 2026-10-20) — verify before relying on it
- ACCA, Manual J (retrieved 2026-10-20)
- City of Dallas, "Current City Code" (retrieved 2026-09-23) — verify before relying on it
- AHRI, "2023 Energy Efficiency Standards"; DOE regional standards (retrieved 2026-09-23)
- NAHB summary of the EPA final rule (May 2026); EPA AIM Act Technology Transitions program (retrieved 2026-09-23)
- ENERGY STAR, "Duct Sealing" (retrieved 2026-10-20)
- Trane, Warranty and Registration (retrieved 2026-10-20)
- Lennox, Extended Limited Warranty FAQ (retrieved 2026-10-20) — verify before relying on it
- Texas Comptroller, Publication 94-116, "Real Property Repair and Remodeling" (retrieved 2026-09-23)
- Texas Business and Commerce Code ch. 601 (retrieved 2026-10-20)
- IRS, Energy Efficient Home Improvement Credit (retrieved 2026-09-23)
- City of Garland, mechanical permits (retrieved 2026-10-20) — verify before relying on it
- City of Carrollton, HVAC trade page (retrieved 2026-10-20) — verify before relying on it
- Cold Factor Heating & Air (Flower Mound, TX) (page dated 2026) (retrieved 2026-09-23)
- HVAC Services Pro (DFW) (page dated 2026-04-13) (retrieved 2026-09-23)
- HVAC Services Pro, DFW installation guide (page dated 2026-03-06) (retrieved 2026-09-23)
- HVACProjectCost.com, Dallas page (page dated 2026-08-02) (retrieved 2026-09-23)
Questions
How many HVAC installers should I get quotes from?
Three is a common choice: enough to spot an outlier without taking weeks. Ask each the same questions so the answers compare.
Should I ask an installer for references?
You can, and check them yourself. This site publishes no contractor reviews and does not vet individual contractors.
Is it rude to ask for the load calculation?
No. Dallas enforces a code that calls for sizing from a load calculation, and asking for the result is a normal homeowner question.
What if an installer will not answer in writing?
Treat that as information. Key items such as model numbers, scope, permit and warranty belong on the written quote or contract.
Do I need to ask about refrigerant?
Yes. New equipment generally uses R-454B or R-32, while some pre-2025 R-410A stock can still be installed. Know which you are buying.
Can I pull the permit myself?
Some cities allow a homestead owner to, which can shift responsibility to you. In most cases the licensed contractor applies. Ask your city.
Next step
Free quote request
Get a quote to check against these numbers
- Tell us about the job. Service, ZIP, property and timing. The form says right away if your ZIP is outside the area.
- We check the license first. Requests go only to contractors whose TDLR air conditioning license we have matched on the state register. None is signed yet: if no checked contractor covers your ZIP, we email you and say so.
- Compare what comes back. Line the written quotes up in the quote-comparison tool.
No cost and no obligation. We are a publisher, not a contractor. Partner contractors will pay us for introductions; none is signed yet. How that works.
Request AC installation quotes
Free and no obligation. We pass a request on only to a contractor whose TDLR license we have checked and who covers your ZIP.