HVAC replacement cost dataset

One visit or two, at each efficiency tier

Both sides come from models on this site, at national wages and identical equipment grade. Only the organisation of the work differs.

⚠️ For this table to mean anything, both sides have to buy the same equipment. Our whole-system model deliberately uses the identical price bands to the furnace and air conditioner pages — an earlier version did not, and the resulting “saving” was an artefact of specifying different boxes rather than of organising the work differently. Any saving reported here comes from labour, permits, commissioning and disposal only.

Three configurations

By house size and climate

⚠️ Both sizes are screening estimates from floor area and climate, and both come from the same shared module the furnace and air conditioner pages use — deliberately, so that two pages of this site cannot give two different sizes for the same house. The professional standard for sizing is ACCA Manual J, which is licensed material and is not reproduced anywhere here. A real calculation frequently comes back smaller.

The cheapest thing available on this day

Sealing the accessible joints while the system is already apart costs $485 more, almost all of it labour. It is the single change most likely to make new equipment perform the way its label says, and it is missing from most quotes because nobody asks for it. Replacing ducts is a different job of a different size and is priced on its own page.

Line items

75% of the reference total comes from estimated rather than official figures, each with its own uncertainty band rather than one applied across the board.

The reasoning behind each figure

Written out so an HVAC contractor can point at the exact assumption that is wrong.

Gas furnace, 80% AFUEestimated, ±33%

• Today’s federal minimum for an indoor gas furnace. Priced per thousand BTU of input, so a 100,000 BTU/h unit lands around $1,100 to $2,200 for the appliance alone.
• ⚠️ Identical band to the one on our furnace page, and that is deliberate rather than tidy. This page’s whole argument is a comparison against replacing the two halves separately, and a comparison is worthless if the two sides are not buying the same equipment. Any saving this page reports has to come from how the work is organised, never from quietly specifying something different.

Gas furnace, 95%+ AFUE condensingestimated, ±31%

• A second stainless heat exchanger, because what comes off it is mildly acidic. Roughly $700 to $1,300 more than the equivalent 80% unit before any of the installation differences it forces.
• Same band as our furnace page, for the same reason as the row above.

Air handler with resistance backup elementsestimated, ±42%

• Cabinet, coil, variable-speed blower and 10 to 20 kW of electric elements, depending on climate and house.
• A heat pump delivers air that is warm rather than hot, so it has to move much more of it, continuously. The blower matters more here than in any gas system, and a cheap one is how a correctly sized heat pump ends up feeling draughty.

Matched indoor coilestimated, ±35%

• Cased coil certified to the outdoor unit and sitting on top of the furnace. The pair is what carries the efficiency rating: the number on the box outside is only true with the coil it was tested against.

Outdoor air conditioner, 13.4 SEER2 (North minimum)estimated, ±29%

• The cheapest split-system condenser it is legal to install outside the Southeast and Southwest.
• Equipment built for the low-GWP refrigerants that replaced R-410A costs more than what it replaced. That is a dated regulatory change, not a market fluctuation.

Outdoor air conditioner, 14.3 SEER2 (Southeast and Southwest minimum)estimated, ±28%

• Same job, same installer, higher legal floor: 10 CFR 430.32(c)(6) requires 14.3 SEER2 rather than 13.4 in the states it names, and an outdoor unit that cannot certify to it may not be installed there.
• About 12% more per ton than the 13.4 unit — our estimate of what nine tenths of a SEER2 point costs at the bottom of the range, where efficiency is bought with a bigger coil rather than with electronics.

Outdoor air conditioner, two-stageestimated, ±24%

• Around 16 SEER2 with two capacity steps. Above the legal floor there is no regional distinction: the rule sets a minimum, not a ceiling.
• Same band as our air conditioner page, because this page’s argument is a comparison and a comparison needs both sides buying the same box.

Outdoor air conditioner, variable-speedestimated, ±25%

• 18 SEER2 and above, inverter-driven, modulating rather than cycling. Quietest and driest, and the tier where an out-of-warranty control board can cost more than a whole minimum-efficiency condenser.
• Same band as our air conditioner page, for the same reason as the row above.

Outdoor heat pump, federal minimum ratingestimated, ±28%

• A heat pump costs more per ton than the equivalent air conditioner because it also runs backwards: a reversing valve, a defrost control, a larger outdoor coil and a base pan heater so meltwater does not freeze the unit to its own pad.
• Single-stage, at the floor. Also the tier that loses the most output on the coldest nights, which is what the backup exists to cover.

Outdoor heat pump, two-stageestimated, ±24%

• Around 16 SEER2. It holds usable capacity further down the temperature scale than the minimum tier, which directly reduces how often the expensive backup runs.

Outdoor heat pump, cold-climate inverterestimated, ±25%

• Specified by its capacity at 5 °F rather than by a seasonal average, which is the number to ask for if your winter is real.
• The difference between a heat pump that heats the house in January and one that hands the job to the backup and watches.

Dual-fuel control and outdoor sensorestimated, ±48%

• A thermostat that can drive both machines and knows which one is cheaper right now, plus the outdoor sensor that tells it the temperature.
• Cheap hardware whose setting is worth more than itself: the crossover should be set from your own gas and electricity rates, not left on a default.

Thermostatestimated, ±75%

• A whole-system replacement always ends with a new thermostat, because the old one rarely has the conductors a staged or reversing system needs.
• Band runs from a basic programmable to a connected one. Both do the thing that saves money; only one needs an account.

Removal, setting and connection, whole system

• Twenty-six trade hours: two technicians for a day and a half. This is the number that carries the argument of this page, so it is worth stating plainly what it is compared against.
• Our furnace model bills 16 hours and our air conditioner model bills 18. Done separately that is 34. Done together it is 26, and the eight hours are not a discount: they are the strip-out done once, the sheet metal set out once, and the refrigerant circuit opened once instead of twice.
• The wage is official and regional; the hours are our estimate. There is no public productivity data for residential trades, so we keep saying which half is which.

Plenums, transitions and sheet metalestimated, ±40%

• Neither cabinet is the same size as what came out, so the sheet metal above and below is remade. Fabricated on site or in the van, not bought off a shelf.
• On a whole-system job this is done once for both halves, which is part of why the total is not the sum of two separate jobs.

Sheet metal fabrication and fitting

• Four hours to measure, cut, fold and seal every transition around both cabinets at once.

Sealing accessible duct joints and pressure-testing

• Six hours of mastic on accessible joints plus a pressure test to prove it, while the system is already open and the crew is already there.
• The cheapest moment in the life of a duct system to do this, and the change most likely to make the new equipment behave the way its label says it will. It does not appear on most quotes because nobody asks for it.

Mastic, mesh and mechanical fastenersestimated, ±46%

• Almost all of duct sealing is labour. The material is a bucket of mastic and a roll of mesh, and the reason it is listed separately is that seeing how little it costs is the argument for doing it.

Metal flue connector to the existing chimneyestimated, ±50%

• An 80% furnace vents hot, so it can use the masonry chimney that is already there. This is the connector between the two, not the chimney itself.

Sealed plastic intake and exhaust through the wallestimated, ±49%

• Two pipes, not one: a condensing furnace draws combustion air from outside and pushes exhaust back out, both sealed.
• The band is run length and whether it exits a wall right at the furnace or has to travel to a legal termination point — which cannot be under a window, near an air intake, or where the plume will ice a walkway.

Coring the wall and running the vent

• Four and a half hours: core the wall, run and support two pipes, pitch them back so condensate drains the right way, seal both ends. Work that does not exist at all on a standard-efficiency swap.

Relining the chimney for the orphaned water heaterestimated, ±44%

• The line nobody warns you about, and on a whole-system job it applies to two of the three configurations: the moment the furnace stops using the masonry chimney, that flue is far too big for a water heater on its own.
• A flue that is too large does not draw. The exhaust cools on the way up, condenses inside the masonry and destroys it from within, while the products of combustion are no longer reliably leaving the house.
• Priced here on the all-electric option, where the furnace disappears entirely. On a condensing furnace it applies too and is priced on our furnace page.

Fitting the liner

• Four hours, most of it on a roof feeding a liner down a chimney.

Gas connection, shutoff and sediment trapestimated, ±42%

• Flexible connector, a shutoff within reach, and the sediment trap — the short capped stub that catches whatever the pipe sheds before it reaches the burner.

Gas fitting and leak test

• An hour and a half to break the connection, remake it and pressure-test it. Priced at the pipefitting wage because that is the skill being used, whoever holds the wrench.

Condensate drain, neutraliser and panestimated, ±56%

• Every system on this page makes condensate in cooling, and a condensing furnace makes several litres a day in cold weather as well.
• The neutraliser is a small canister of limestone chips in the drain line. Cheap, often skipped, and skipping it is what eats a cast iron waste stack from the inside.

New refrigerant line setestimated, ±39%

• Thirty feet assumed, which suits a condenser beside the house and an indoor unit in a basement or a closet.
• Replacing rather than reusing is the right call after a compressor burnout, when the diameter is wrong for the new equipment, or when the insulation has spent fifteen years in the sun.

Running and brazing the line set

• Three hours: pull the old pair, run the new one, braze under flowing nitrogen so the inside of the pipe does not scale, and insulate.

Flushing and pressure-testing the existing line setestimated, ±48%

• Solvent and nitrogen. Small money, and the step that decides whether reusing the pipe was clever or catastrophic: oil and acid left from old equipment will destroy a new compressor and nothing covers that.

Filter drier and service valvesestimated, ±57%

• A new drier on every changeout: it absorbs the moisture that gets in while the system is open, and moisture plus refrigerant makes acid.
• Bi-flow on a heat pump, because there the refrigerant runs both ways and an ordinary one-way drier would be a restriction half the year.

Evacuation and refrigerant chargeestimated, ±50%

• Deep vacuum to boil off moisture, then weighed-in charge. Priced per ton because it scales with capacity and line length.
• The band widened with the refrigerant transition: the low-GWP fluids that replaced R-410A cost more per pound, and some are mildly flammable, which changes how they are stored and handled.

Refrigerant recovery from the old system

• Two hours with recovery equipment before anything is cut. EPA rules under Section 608 prohibit knowingly venting these refrigerants while servicing or disposing of equipment.
• Also the clearest single signal about who you have hired: a crew that cuts the line and lets it hiss is telling you what the rest of the job will look like.

Pad or raised stand for the outdoor unitestimated, ±64%

• A composite pad for an air conditioner; a raised stand where a heat pump has to shed defrost meltwater above the snow line, which is not a nicety but what stops the unit freezing itself into a block of ice.

Disconnect, whip, breakers and backup feederestimated, ±85%

• Bottom of the band is a pull-out disconnect and a whip for a gas system. Top is that plus a feeder for 15 kW of resistance backup on the all-electric option, which is around 62 amps at 240 volts.
• ⚠️ Assumes the panel has both the physical space and the spare capacity. When it does not, a panel upgrade is a separate job — and it is the commonest reason an all-electric quote lands far above expectation.

Electrical work

• Two hours on a gas system to swap the disconnect and confirm the breaker matches the plate. Six on the all-electric one, where a backup feeder is run and terminated at both ends.

Start-up and commissioning of the whole system

• Three and a half hours to verify the charge by superheat or subcooling, measure the temperature split, check airflow, and on anything that burns fuel put an analyser on the flue and set the gas pressure.
• Done separately our two models bill two hours each. One visit needs less than two, and this is where the efficiency you paid for is either delivered or quietly lost.

Old equipment removal and disposalestimated, ±46%

• One trip with both halves on it rather than two trips a year apart. Partly offset by scrap value: a furnace is mostly steel and a condenser is mostly copper and aluminium.

Mechanical and electrical permitestimated, ±58%

• One permit for one job. Replacing the two halves two years apart means two permits and two inspections, which is a real part of what doing it at once saves.
• Fees are set by each jurisdiction with no national schedule, hence a band. The inspection is also the only independent check that the flue and the gas connection were done correctly.

Not included in this dataset

Replacing or resizing the ductwork

Sealing accessible joints is offered here because it is cheap while the system is open. Replacing ducts is a different job of a different size, and it is priced on our ductwork page.

Electrical panel or service upgrade

Every figure assumes the panel has room and capacity for what the new system needs. When it does not, that is a separate job — priced on our electrical panel page.

A Manual J load calculation

The sizing here is a screening estimate from floor area and climate, not a room-by-room load calculation. A real one costs money and frequently comes back smaller than any rule of thumb.

Zoning, dampers or a second system

Above about five tons a house is normally split into two systems or zoned. Neither is modelled here.

Oil-fired equipment and boilers

Oil furnaces have a tank, a filter and a nozzle; boilers heat water rather than air and have no ducts at all. Boilers are priced on our boiler page.

Asbestos on old duct joints or flue cement

Houses from before the eighties can have it. It is tested rather than disturbed, and abatement is licensed work with its own pricing.