Furnace and AC Replacement Cost Calculator
Estimate the cost to replace a home's furnace and air conditioner together from equipment and labor cost per system.
How this calculator works
This estimates the cost to replace a furnace and air conditioner together as one project. It multiplies the number of systems you’re replacing by an equipment cost per system, then adds the number of systems times a labor cost per system, to get a total.
Formula: Total cost = number of systems × equipment cost + number of systems × labor cost.
Worked example
Replacing 1 combined furnace+AC system, $4,500 equipment, $2,000 labor:
- Equipment cost: 1 × $4,500 = $4,500
- Labor cost: 1 × $2,000 = $2,000
- Total estimated cost: $6,500
Notes
Replacing both units together often costs less over time than replacing them separately, since one crew handles both jobs and the ductwork and electrical connections are only touched once instead of twice. Matched furnace and AC systems — designed and sized to work as a pair — can also run more efficiently together than mismatching a new unit with an older one that’s nearing the end of its life.
Equipment cost per system depends heavily on the size (tonnage) and efficiency rating of the units you choose, and labor cost depends on your region and how accessible the existing equipment is. Both fields in this calculator are placeholders you should replace with real quotes from local HVAC contractors.
How to use
Enter the number of furnace-and-AC systems you’re replacing, along with an equipment cost and a labor cost per system based on contractor quotes. The calculator multiplies each rate by the system count and adds them together for a total project estimate.
Estimates only. Actual cost depends on your region, material choice, and site conditions — get a contractor quote before budgeting.
Frequently asked questions
Why replace a furnace and AC together instead of separately?
Replacing both at once means one crew visit instead of two, and the ductwork, electrical, and thermostat connections only get touched once. Matched furnace and AC systems are also designed to work together efficiently, which is harder to guarantee when you pair a new unit with an aging one.
What counts as 'one system' in this calculator?
One system is one combined furnace-plus-AC replacement for a home or zone. If your home has two separate HVAC zones (for example, upstairs and downstairs), each zone with its own furnace and AC pairing counts as a separate system in the count field.
Does this include ductwork or electrical upgrades?
No. This estimate only covers equipment and labor cost per system. Ductwork repair or replacement, electrical panel upgrades, permits, and removal/disposal of old equipment are separate costs that a contractor would quote on top of this number.
Why do equipment and labor costs vary so much between quotes?
Equipment cost depends on the brand, efficiency rating (SEER/AFUE), and tonnage sized for your home. Labor cost depends on your region, access to the equipment, and whether extra work like a new line set or condensate line is needed. Get at least two local quotes before budgeting.
Estimates only. Verify quantities with your supplier before purchasing.