HVAC cost calculator · Full system
Furnace + AC Cost Calculator
Estimate the cost of replacing both your gas furnace and central air conditioner — sizing, efficiency, ductwork, and local labor included.
Average cost $8,000–$20,000
Quick Furnace + AC Estimate
Get a localized installation range in seconds — no signup required.
Advanced Furnace + AC Calculator
Personalize AC tonnage, furnace efficiency, ductwork, and upgrades for a complete HVAC replacement estimate.
What Is Furnace + AC?
Full system conditioning cools your entire home through a single outdoor condenser and indoor air handler connected to ductwork. A thermostat controls temperature room-by-room via supply vents.
- Whole-home cooling — one system, even temperatures
- Duct-driven airflow — works with existing furnace ducts in most homes
- Thermostat controlled — programmable and smart thermostat compatible
Furnace + AC Cost by Home Size
Installed averages at 16 SEER with existing ductwork — updates for your selected city.
| Home size | Avg installed cost | Typical tonnage |
|---|
Furnace + AC Cost by SEER Rating
Higher SEER costs more upfront but lowers monthly cooling bills.
| SEER | Avg cost | Energy savings |
|---|
Furnace + AC System Types
Furnace efficiency (AFUE) and AC SEER drive total installed cost.
Two-stage
Variable-speed
Furnace + AC Pros & Cons
Advantages
- Strong heating in cold winters
- Familiar technology for most contractors
- Whole-home comfort through existing ducts
- Can stage upgrades (furnace now, AC later) but combo often saves labor
Disadvantages
- Higher total cost than AC-only replacement
- Two fuel types if you also consider heat pumps later
- Requires well-maintained ductwork for both seasons
Furnace + AC vs Other Systems
Furnace + AC vs Heat Pump
Cooling-only vs heat + cool in one system — compare installed costs.
Read comparison →Furnace + AC vs Mini Split
Ducted whole-home vs ductless zoning — which fits your home?
Compare systems →Furnace + AC vs Window AC
Whole-home comfort vs room-by-room budget cooling.
Full HVAC calculator →HVAC Systems by Type
Compare installed cost ranges for every major system.
Local Furnace + AC Cost Factors
Based on the city selected in the calculator above.
National average
- Typical install: 3-ton · 16 SEER · existing ducts
- Peak season: Summer demand for AC replacements
- Sizing: ~1 ton per 500–600 sq ft (moderate climate)
- Note: Gas furnace + AC common in northern and midwestern markets
Your city
Furnace + AC Installation Timeline
System selection
1 day
Choose tonnage, SEER, and brand with your contractor.
Installation
1–2 days
Furnace swap, AC condenser, coil, flue checks, and full system test.
Duct adjustments
1–3 days
If needed — sealing, sizing, or partial replacement.
Inspection
Several hours
City permit inspection after install completes.
Best Furnace + AC Brands
Price tiers and typical warranty coverage (2026).
| Brand | Price tier | Typical warranty |
|---|---|---|
| Carrier | $$$ | 10 yr parts · 1–5 yr labor |
| Trane | $$$ | 10 yr parts · registered labor |
| Lennox | $$$ | 10 yr parts · variable by series |
| Goodman | $ | 10 yr parts · budget-friendly |
| Rheem | $$ | 10 yr parts · solid mid-range |
Real Furnace + AC Installation Examples
Based on the city selected in the calculator above.
National average
16 SEER AC + 80% furnace · 2,000 sq ft
- 3-ton · standard replacement
- Final cost: $9,200
Your city
16 SEER AC + 80% furnace · 2,000 sq ft
- 3-ton · existing ductwork
- Final cost: —
Austin, TX — Local Cost Context
Prices on this page adjust for Austin-area labor, permits, and climate — not a generic national template.
Labor
Austin's tech-driven growth keeps remodel and energy-upgrade crews busy. Central Texas contractors compete on design-forward kitchens and heat-pump installs, though hail season still creates roofing bottlenecks.
Contractor labor runs about 7% below the U.S. average; typical permit fees in our model start around $228 for standard residential work.
Permits
City of Austin and suburban Williamson/Hays jurisdictions require permits for structural roof work, HVAC changeouts, and most electrical upgrades. Energy code is stricter than many Texas metros.
Climate
Central Texas blends long heat with occasional hard freezes:
- Extended cooling season favors variable-speed and heat-pump systems
- Spring hail events create sudden roofing labor shortages
- Clay soil movement affects foundations, fences, and patio slabs
Top local projects
- Heat-pump HVAC upgrade — Handles mild winters and long summers efficiently
- Kitchen open-concept remodel — Top request in 1980s–2000s Austin tract homes
- Solar + battery storage — Rising Austin Energy rates improve payback
Furnace + AC Cost FAQ
How much does Furnace + AC cost?
Furnace + AC installation typically costs $8,000–$20,000 nationally in 2026, depending on home size, tonnage, SEER, ductwork, and location. Use the calculator above for a localized range.
What size AC do I need?
Plan on about 1 ton per 500–600 sq ft in moderate climates — a 2,200 sq ft home often needs a 3–4 ton unit. Hot climates may need slightly more capacity. Always confirm with a Manual J load calculation.
Is 16 SEER worth it?
For most homes, 16 SEER is the sweet spot: modest upfront premium over 14 SEER with meaningful energy savings. In hot states like Texas or Arizona, payback is often under 7 years.
Does installation include ductwork?
Standard replacement usually reuses existing ducts. New ductwork adds roughly $2,800–$6,500+ depending on home size — toggle it in the advanced calculator.
How long does installation take?
Most central AC replacements take 1–2 days for installation, plus permit lead time. Duct work or electrical upgrades can extend the schedule to 3–5 days.