About the data
Every range the decoder uses, with its source. Nothing here is our own estimate — when no published national range exists, the decoder says so instead of inventing one.
How the decoder works
The decoder compares each line item you enter against a published national range from the 2025-26 cost guides listed below. Anything above its range gets an "Ask about" flag and a specific question; anything below gets a "confirm what's included" note. The fair-total range is plain arithmetic: the installed-system range for your job type and home size, plus the published range of each extra you entered. We never average sources together, and we never extrapolate a number a source didn't publish.
Two line items have no benchmark on purpose: maintenance/service plans and bundled "other add-ons." No national guide publishes a defensible range for either, so the decoder passes them through at face value and arms you with a question instead.
These are national ranges. A dense coastal metro will run above them; a lower-cost region will run below. A quote slightly over a range is a conversation, not a verdict — the point is to know which conversation to have. This is a planning tool, not a quote, an appraisal, or professional advice.
Installed-system ranges (equipment + labor)
AC + furnace, installed — smaller home (under ~1,300 sqft): $ 5,000 – $ 12,500. Replacing both at once averages $7,500 nationally ($5,000-$12,500). Source: Angi (2026) .
AC + furnace, installed — larger home (over ~2,000 sqft): $ 7,000 – $ 20,000. Basic central AC + furnace for a ~2,000 sqft home runs $7,000-$20,000. Source: This Old House, via CBS News (May 2026) .
Central AC, installed — smaller home (under ~1,300 sqft): $ 2,500 – $ 5,500. A ~2-ton central AC for ~1,200 sqft installs for $2,500-$5,500. Source: PickHVAC (2025) .
Central AC, installed — mid-size home (~1,300-2,000 sqft): $ 3,300 – $ 7,800. A 3-ton unit for a 2,000 sqft home averages $5,750 installed ($3,300-$7,800). Source: HVAC.com (Mar 2025) .
Central AC, installed — larger home (over ~2,000 sqft): $ 4,000 – $ 8,000. A ~5-ton unit for ~3,000 sqft runs $4,000-$8,000; high-SEER2 or new ducts push past $10,000. Source: PickHVAC (2025) .
Gas furnace, installed — smaller home (under ~1,300 sqft): $ 3,800 – $ 10,000. Replacement averages ~$7,000 for 1,600-2,000 sqft ($3,800-$10,000; 96%+ AFUE up to $12,000). Source: Angi (2026) .
Ducted air-source heat pump, installed — smaller home (under ~1,300 sqft): $ 4,500 – $ 12,000. Ducted air-source systems typically run $7,500-$11,000, with extremes of $4,500-$12,000. Source: EnergySage (2025) .
Extra line items
Permit / inspection: $ 75 – $ 500. Replacement permits typically run $75-$300 flat or $100-$250; some metros charge up to $1,500 for new installs. Source: PermitFlow ; HomeGuide (2026) .
Installation labor (when itemized): $ 500 – $ 3,000. Furnace labor runs $500-$2,000; at the $75-$150/hr trade rates guides report, a two-tech, 1-2 day install implies up to ~$3,000. Source: HomeGuide (2026) ; HomeAdvisor (2025) .
Duct repairs / modifications: $ 1,000 – $ 3,000. Repairing damaged, undersized, or leaky ducts typically costs $1,000-$3,000. Source: EnergySage (2025) .
Full ductwork replacement: $ 1,400 – $ 5,600. Whole-house replacement averages $1,400-$5,600; complex homes run far higher. Source: HomeGuide (2026) .
Thermostat (device + install): $ 115 – $ 400. Pro install averages $114-$264; a smart thermostat installed runs $225-$400. Source: HomeAdvisor (2026) ; HomeGuide (2026) .
Old-unit removal / disposal: $ 60 – $ 500. Removal and disposal of the old system runs $60-$500. Source: Bob Vila .
Two 2025-26 facts the questions lean on
- The federal 25C Energy Efficient Home Improvement Credit ended for equipment placed in service after December 31, 2025 — a 2026 install cannot claim it. Utility and state rebates still exist. Source: IRS.
- Under the EPA's AIM Act phase-down, new systems manufactured since January 1, 2025 use A2L refrigerants (R-454B or R-32) instead of R-410A, and the industry reported double-digit equipment price increases and refrigerant supply squeezes through the transition. Source: Trane.
Disclosures
Referrals: the "compare local HVAC quotes" button on the decoder page may be a referral link; if it is, we may earn a commission at no cost to you. No contractor pays to influence the benchmark ranges above, and nothing you type into the decoder is shared with anyone — referral or otherwise.
Privacy: the decoder runs entirely in your browser. Your quote numbers are never sent to a server. Site analytics, when enabled, record only that a decode happened (job type, home size, total, flag count) — never the line items.
Accessed: all sources above were checked June 2026. If a guide updates its numbers and we haven't caught up, the source link wins — and we'd like to know.