Best Furnace & AC System Replacement in Marietta, GA
What to look for in Furnace & AC Replacement in Marietta
A whole-system changeout is the moment to right-size with a Manual J load calc and match the furnace, coil, and condenser so the rated efficiency is real. We weight installers who publish matched-system practice, manufacturer authorization, and Manual J sizing for the full job.
- Whole-system / matched install. Provider names furnace-plus-AC or furnace-plus-coil system replacement as a matched changeout — not two separate, unmatched halves.
- Manufacturer authorization + labor warranty. Factory-authorized status and a multi-year labor warranty preserve coverage across the whole new system.
- Manual J sizing. An ACCA Manual J load calculation right-sizes the system instead of copying the old (often oversized) equipment.
Verify before you book
- Whether a Manual J load calculation was actually performed — ask to see the load-calc result.
- That the furnace, coil, and condenser form a matched combination — request the model numbers and AHRI listing.
- License status with your state board — verify TDLR (TX), ROC (AZ), DBPR (FL), or your local equivalent before paying.
Furnace & AC Replacement in Marietta: matched system + sizing
A whole-system changeout is the moment to right-size with a Manual J load calc and match the furnace, coil, and condenser so the rated efficiency is real. Here is what each of the 4 installers below publishes: In Georgia, HVAC contractors hold a Conditioned Air Class I or II license through the Secretary of State — verify before signing.
Top picks
E. Smith Heating & Air Conditioning★ Best for Furnace + AC Changeout
Consistently strong customer feedback (4.9★ from 1,830+ Google reviews).
Google 4.9★ (1,830+)
Consistently strong customer feedback (4.9★ from 1,075+ Google reviews; 3.4★ from 10+ Yelp reviews).
Google 4.9★ (1,075+)Yelp 3.4★ (10+)
Consistently strong customer feedback (4.8★ from 10,410+ Google reviews; 2.1★ from 355+ Yelp reviews).
Google 4.8★ (10,410+)Yelp 2.1★ (355+)
Consistently strong customer feedback (4.8★ from 10,920+ Google reviews; 1.9★ from 365+ Yelp reviews).
Google 4.8★ (10,920+)Yelp 1.9★ (365+)
Typical Furnace & AC Replacement costs in Marietta, GA (2026)
Last updated
Estimated ranges for Marietta, GA. Actual cost varies with home size, equipment, and scope — always request a written quote for your job.
| Service | Typical range |
|---|---|
| Full gas furnace replacement (80% AFUE, installed) | $2,650–$5,700 |
| Full AC system replacement (paired changeout, installed) | $4,850–$11,450 |
Why Marietta's winters make choosing a "Furnace Replacement" contractor different
Marietta winters bring chilly nights and occasional freezes that expose aging heating systems in older bungalows and brick ranches. Choosing the best furnace replacement companies in Marietta, GA matters because local installers know county codes and common duct layouts. Also consider advertised warranties and emergency service availability.
How quickly do Marietta "Furnace Replacement" pros usually respond and what should I ask?
- Should I replace the furnace and AC at the same time?
- If both are near end of life, replacing together gives you one matched, right-sized system, one labor mobilization, and aligned warranties — often cheaper than two separate jobs. If only the furnace has failed and the AC is newer, a good installer confirms the new furnace and coil work with your existing equipment instead of upselling the pair.
- Does replacing both as a system improve efficiency?
- Yes, when it's done as a matched set. The furnace, indoor coil, and AC condenser are rated to work together, and a whole-system changeout is the moment to right-size with an ACCA Manual J load calculation rather than copying the old (often oversized) equipment. Ask the installer to size the whole system, not just swap boxes.
- Will replacing a furnace at the same time as an air conditioner change permit or code requirements in Marietta?
- Possibly. Combined furnace and AC replacements can affect ductwork, airflow, and IECC efficiency compliance. That can change permit scope. Ask whether the contractor includes duct work, airflow testing, and permit submission in a combined-project quote to ensure installations meet local code.
- How do I find a high-efficiency furnace specialist in Marietta?
- Look for providers who document Manual J load calculations and list high-efficiency furnaces with manufacturer-dealer status. Ask for written load calculations, equipment efficiency ratings that meet the 2021 IECC, and examples of recent installs in similar brick ranch or bungalow homes. Verify technician NATE or manufacturer certifications.
- How do I get a quote from these furnace replacement companies?
- Submit one request on this page and we send it to the vetted furnace replacement pros in Marietta, GA listed here. They send quotes back — no obligation.