Furnace Replacement Cost in San Antonio (2026 Guide)
If your furnace is on its last legs, the first question is always the same: what is this going to cost me? Here are honest, installed price ranges for the San Antonio area — no games, no "call for pricing" runaround.
The short answer
Most furnace replacements in San Antonio land between $6,000 and $8,400 installed for a solid, dependable system. High-efficiency models run $9,000 to $13,500. If you are replacing the furnace and the air conditioner at the same time — which most homeowners do, since the two share the blower and ductwork — a full system starts around $6,000 and tops out near $16,500 for premium equipment.
What changes the price
Brand choice. We install four brands because each fits a different homeowner:
- Goodman — from $6,000. The value pick. Same factories and components as many pricier names, backed by a strong warranty.
- Carrier — from $8,000. The quiet, refined option with a long track record.
- Armstrong — from $8,000. Built tough, a favorite of technicians who work on them.
- American Standard — from $12,000. The premium choice, and we are an authorized dealer.
Efficiency rating. A standard-efficiency furnace costs less up front. A high-efficiency model (96%+ AFUE) costs more but burns less gas every winter. In San Antonio, where winters are short and mild, standard efficiency is often the smarter buy — we will show you the math both ways.
Your home. Size, ductwork condition, gas line and venting, and whether the furnace sits in an attic, closet, or garage all affect labor. Two homes with the same furnace can legitimately get different quotes.
Repair or replace?
Our philosophy is repair first. If a $300 ignitor or a $200 flame sensor gets you safely through another five winters, that is what we will recommend. Replacement starts making sense when the heat exchanger is cracked (a safety issue, not a comfort one), when the furnace is 15+ years old and a major part fails, or when repair bills are stacking up season after season.
What you get with us
Every installation includes a 10-year parts warranty, a 2-year labor warranty, and a 2-year service agreement. The work is done by our own trained in-house crews — never subcontracted to whoever was available that week.
Get a real number
Text us a few details about your home — square footage, the age of your current furnace, and a photo of the data plate if you can find it — and Clint will give you an honest quote right over the phone or by text. No pressure, no salesman, just a straight answer from the owner.
Call or text Carnes and Sons today and know your real number before the first cold front hits.