Most homeowners in Oakland County, Michigan pay about $11,000 to $15,000 to replace a furnace and central air conditioner together in 2026, installed. Our furnace and AC replacements this past year averaged about $13,200. Basic systems start around $8,200, and premium systems or jobs with new ductwork run up to about $22,900.
Replacing just the furnace? Most furnace-only installs run $4,300 to $7,500. See our new furnace cost guide. Just the air conditioner? See our AC replacement cost guide.
| System | Furnace + AC | Installed cost (2026) |
|---|---|---|
| Good Rheem Classic | 80% AFUE furnace + 13–14 SEER2 AC | $8,200 – $10,900 |
| Better Rheem Classic Plus | 95% AFUE furnace + 16–17 SEER2 AC | $10,600 – $13,300 |
| Best Rheem Prestige | 96% AFUE furnace + 17–19 SEER2 AC | $13,900 – $22,900 |
Furnace and AC replaced together in Oakland County, before rebates. Many homes mix and match: a 95% furnace with a standard AC typically runs $11,000 to $12,600. AC size, ductwork, and electrical work move a job within its range.
How we priced this: these ranges are our own installed prices for furnace and AC systems, the same ones the calculator below uses. Across the furnace and AC replacements we completed in Oakland County over the past 12 months, the average job came in around $13,200. Prices reviewed by John Serrano, October 2026.
National cost sites often quote around $7,500 for a new furnace and AC. Those averages blend smaller homes, milder states, and some equipment-only prices. Ours are installed prices for Michigan homes, with a furnace sized for our winters, and they include removal of the old equipment, startup, and the labor warranty.
Included in a full system replacement
- New Rheem furnace sized to your home
- New outdoor AC unit and matching indoor coil
- New thermostat
- Equipment pads
- Refrigerant, gas, electrical, drain, and duct connections
- Removal and recycling of the old equipment
- Startup, safety check, and cleanup
- 1-year labor warranty, plus Rheem’s manufacturer warranties
Can add to a system price
- A new refrigerant line set between the indoor and outdoor units
- Electrical disconnect or panel upgrades
- Duct repairs or new ductwork
- Humidifiers, air cleaners, or zoning
- New PVC venting when moving to a high-efficiency furnace
- Hard-to-reach locations like attics and crawlspaces
Get your furnace and AC price in 30 seconds
Pick the systems you need replaced and answer a few quick questions. The calculator uses our real installed prices. It’s also on our instant HVAC price page.
What did recent furnace and AC replacements cost?
Here are four furnace and AC replacements we completed in Oakland County in the past year, with the total installed price:
| Town | What we installed | Installed price |
|---|---|---|
| Lake Orion | 80% furnace (50,000 BTU) + 2-ton AC | $9,924 |
| Oxford, 1,700 sq ft home | 95% furnace (70,000 BTU) + 3-ton AC | $11,142 |
| Ortonville | 96% Rheem Prestige furnace + 2.5-ton AC + humidifier | $13,720 |
| Oxford | 80% furnace (125,000 BTU) + 4-ton AC + humidifier | $16,075 |
Each price included the equipment, installation, removal of the old system, startup, and the 1-year labor warranty.
How much does a furnace and AC cost for my home size?
Most Oakland County homes we replace use a 2- to 3-ton air conditioner with a 60,000 to 85,000 BTU furnace, and those systems usually land between $10,000 and $13,000. Larger homes that need a 4-ton AC and a bigger furnace often run $12,000 to $16,000.
Size moves the price less than you might expect. In the same Rheem line, going from a 2-ton to a 4-ton air conditioner adds about $1,200. Efficiency level, ductwork, and electrical work make a bigger difference. The right size for both pieces comes from a load calculation for your home: insulation, windows, layout, and air leaks matter as much as square footage.
Size the furnace and AC together, not separately. An air conditioner that’s too big for the house cools it quickly but shuts off before it pulls the humidity out, so the house feels cold and damp. The furnace’s blower also has to move the right amount of air for the AC, which is one more reason to plan both at once.
Should you replace your furnace and AC at the same time?
If both are 10 years old or more, usually yes. Replacing them together costs less than doing them a few years apart, and you get equipment that’s designed to work together.
When replacing both saves money
- One install instead of two. The crew, the setup, and the startup happen once.
- A matched system. The AC’s indoor coil sits on top of the furnace. New air conditioners use a newer refrigerant, and the coil has to match the new outdoor unit.
- One warranty start date and one project to plan and finance.
- Less chance of a second emergency. If the 15-year-old furnace just failed, the AC of the same age is often close behind.
When replacing just one makes sense
If your air conditioner is only 5 or 6 years old and working well, replace just the furnace (see our new furnace cost guide). If your furnace is fairly new and the AC is the one failing, see our AC replacement cost guide.
Replacing only the furnace now? Ask what the AC job will need later. A new air conditioner usually needs a new indoor coil on top of the furnace. Get that coil price in both quotes so you can compare “furnace now, AC later” against “both now.”
Is a high-efficiency furnace and AC worth it in Michigan?
In Michigan, put your efficiency money into the furnace first. Our heating season is long and our cooling season is short, so a high-efficiency furnace pays back far faster than a high-efficiency air conditioner.
A 95% or 96% furnace burns about one-sixth less gas than an 80% furnace for the same heat. Our furnace cost guide walks through that math.
Air conditioners are rated in SEER2. The federal minimum for a new central air conditioner in Michigan is 13.4 SEER2, and that’s what most standard systems are. A 16 or 17 SEER2 unit uses less electricity, runs quieter, and qualifies for utility rebates, but with only a few months of cooling a year, the savings build slowly.
Check the AC’s SEER2 number before you pick a system. Utility AC rebates start at 15.2 SEER2, so a standard 13.4 SEER2 air conditioner gets $0 back. Stepping up to a 16 SEER2 unit earns $200 from DTE or $300 from Consumers Energy, which covers part of the price difference.
What can raise your furnace and AC quote?
- The refrigerant line set. The copper lines between the indoor coil and outdoor unit are sometimes reused and sometimes replaced, depending on their size and condition.
- Electrical work. A new outdoor disconnect, a new breaker, or, in some older homes, a panel upgrade.
- Ductwork. ENERGY STAR estimates a typical home’s duct system loses 20 to 30 percent of the air moving through it. Sealing or replacing bad ducts costs extra but helps the new system deliver what you paid for.
- Comfort add-ons. Whole-home humidifiers, air cleaners, and zoning for homes with rooms that never feel right.
- Older materials. Some older homes have asbestos tape or insulation on ducts, which has to be handled properly before work begins.
- Venting and access. New PVC venting for a high-efficiency furnace, and extra labor for attic, crawlspace, or tight utility room installs.
What rebates can lower the cost of a new furnace and AC in 2026?
A full system can earn two rebates: one for the furnace from your gas company and one for the air conditioner from your electric company. In parts of Oakland County those are two different companies, so check both bills. Each utility requires a participating contractor. Amounts below were last verified October 24, 2026.
Furnace rebate (from your gas company)
For a 95% or higher furnace, DTE pays $100 to $400 and Consumers Energy pays $100 to $300, depending on efficiency. DTE is adding a $300 bonus on qualifying furnaces installed October 1 through December 15, 2026. Our new furnace cost guide lists every furnace rebate tier.
Air conditioner rebates (from your electric company)
| AC efficiency | DTE | Consumers Energy |
|---|---|---|
| 15.2 to 15.99 SEER2 | $100 | $150 |
| 16 to 17.99 SEER2 | $200 | $300 |
| 18 SEER2 or higher | $300 | $300 |
AC rebate details are on DTE’s air conditioner rebate page and Consumers Energy’s heating and cooling rebate page.
A DTE customer who picks a 96% furnace and a 16 SEER2 air conditioner can get $400 back, or $700 while the fall furnace bonus runs. With a 95% or 96% furnace, the most you’d typically get is $500 from DTE (with an 18 SEER2 AC) or $400 from Consumers Energy (with a 16 SEER2 AC). Both utilities say rebate checks arrive 6 to 8 weeks after the work. There’s no federal tax credit for a 2026 system; that credit stopped with 2025 installs (IRS details), so utility rebates are the main way to save.
Add up rebates by company. The furnace rebate goes to whoever bills you for natural gas, and the AC rebate goes to whoever bills you for electricity. If those are DTE for one and Consumers Energy for the other, you’ll file with both, and we’ll tell you which ones your new system qualifies for.
How long does a furnace and AC replacement take?
Plan on most of a day. On our furnace and AC jobs this past year, the crew was on site about 5 hours, typically 3 to 6, including startup and testing of both systems. Jobs with new ductwork or electrical upgrades can take a second day.
How can you pay for a new furnace and AC?
Wisetack financing covers furnace and AC projects up to $65,000, and seeing your options won’t affect your credit score. Current terms are on our financing a new furnace and AC page.
Check your financing options before the system dies. Knowing your monthly payment ahead of time lets you replace on your schedule, in spring or fall, instead of during a breakdown in January or July.
Frequently asked questions about furnace and AC replacement
How much does it cost to replace a furnace and AC in Michigan in 2026?
Most homeowners in Oakland County pay about $11,000 to $15,000 to replace a furnace and central air conditioner together, installed. Our furnace and AC replacements this past year averaged about $13,200. Basic systems start around $8,200, and premium systems or jobs with new ductwork run up to about $22,900.
Is it cheaper to replace the furnace and AC together?
Usually, yes. One installation costs less than two separate ones a few years apart, and a new air conditioner needs an indoor coil matched to it, which sits on the furnace. ENERGY STAR suggests considering replacement when an AC is more than 10 years old or a furnace more than 15. If one unit is much newer and working well, replacing just the other usually makes more sense.
How long do a new furnace and AC last?
With yearly maintenance, a gas furnace typically lasts 15 to 20 years and a central air conditioner 12 to 15 years in Southeast Michigan. A spring AC check and a fall furnace tune-up help both reach the long end of that range.
Will I need a new electrical panel?
Usually not. Most homes can take a new furnace and AC on the existing panel with a new breaker and outdoor disconnect. Some older homes with small or full panels need an upgrade, and that shows up on the quote before any work starts.
Are HVAC replacement costs tax deductible?
Generally not for the home you live in. The IRS treats a new system as an improvement that adds to your home’s cost basis, which can lower taxable gain when you sell, rather than a deduction. The federal efficiency credit ended for equipment installed after December 31, 2025. Rentals and home offices follow different rules, so check with a tax professional.
When is the best time to replace a furnace and AC?
Spring and fall. Mild weather means the house stays comfortable on install day while both systems are swapped, and fall 2026 installs can also qualify for DTE’s limited-time furnace bonus.
What brand of furnace and AC do you install?
We install Rheem furnaces and air conditioners in three lines: Classic, Classic Plus, and Prestige. Matching the furnace and AC from the same line keeps the system working together as designed.
Sources
- Furnace Rebates and Offers, DTE Energy
- Air Conditioner Rebates and Offers, DTE Energy
- Heating and Cooling Rebates, Consumers Energy
- Energy Efficient Home Improvement Credit, Internal Revenue Service
- Duct Sealing, ENERGY STAR
- Installed prices: Oakland Heating & Cooling completed jobs and online price calculator, October 2026
