A Rheem Classic 90 Plus furnace typically costs about $3,500-$7,500 installed, with many straightforward replacements near $5,200. The final price depends on furnace size, venting and gas-line work, local labor rates, and whether the job includes duct repairs or a new thermostat.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Furnace equipment | $1,500 | $2,300 | $3,400 | Unit price varies by capacity and seller |
| Installed replacement | $3,500 | $5,200 | $7,500 | Standard removal and installation |
| Installed cost per heating ton | $1,200 | $1,750 | $2,500 | Approximate comparison measure |
| Venting or duct changes | $250 | $900 | $2,500 | Added when existing systems need modification |
Assumptions: U.S. residential natural-gas installation, typical access, standard warranty, and no major duct replacement.
What a Rheem Classic 90 Plus replacement usually costs
For a like-for-like replacement, a reasonable budget is $3,500-$6,000 installed. A larger furnace, difficult removal, code updates, or extensive vent changes can raise the quote to $6,000-$7,500 or more. Equipment-only pricing is commonly $1,500-$3,400 before labor, delivery, and installation materials.
The Classic 90 Plus is a 90%-AFUE-class gas furnace, so it uses high-efficiency venting rather than a conventional metal flue in many configurations. Actual specifications and compatibility depend on the model number and home setup. Compare quotes using the same furnace capacity, included work, and warranty terms.
How equipment, labor, and venting shape the quote
Quotes differ because the furnace is only one part of the job. The table gives typical cost ranges for a replacement; charges can overlap when a contractor bundles installation materials and labor.
| Quote item | Typical price | What it covers |
|---|---|---|
| Furnace equipment | $1,500-$3,400 | Gas furnace, before installation |
| Labor | $1,200-$2,500 | Removal, setting, connections, startup |
| Venting and condensate | $250-$1,200 | PVC vent adjustments and drain handling |
| Permits and inspection | $50-$350 | Local permit and required inspection |
| Removal and disposal | $100-$400 | Old furnace handling and haul-away |
| Thermostat or accessories | $100-$600 | Basic control replacement or add-ons |
A contractor may quote a single installed amount rather than itemize every task. Labor illustration: 8-12 hours at roughly $100-$180 per hour for a two-person crew, with rates and crew billing practices varying by market. Ask whether startup testing, permit fees, and haul-away are included before comparing totals.
How furnace size, AFUE, and vent runs change price
Capacity is a major price and fit variable. Residential furnaces commonly fall around 40,000-100,000 BTU per hour, but the correct size should come from a heat-loss calculation, not simply the old furnace label. Moving from a smaller unit to an 80,000-100,000 BTU model can add roughly $300-$900 in equipment and setup costs.
Venting can be another decisive detail. A short, accessible PVC run may need only minor adjustments, while a run over 20-30 feet, multiple elbows, or a route through finished space can add $300-$1,500 or more. A 90% AFUE furnace also needs condensate drainage; a missing drain route or pump can add $150-$500.
Quote changes may also reflect a different efficiency tier, blower configuration, or control system. Request the exact model number and confirm that the proposed capacity and vent layout meet manufacturer instructions and local code.
Lower-cost choices for a Rheem furnace installation
The most controllable savings usually come from limiting unnecessary scope. If the existing return duct, gas line, vent path, and thermostat are in sound condition, ask the contractor to price a standard replacement separately from optional upgrades. Keep required safety or code work distinct from convenience add-ons.
Compare at least three written quotes with matching equipment capacity, model, permit responsibility, disposal, labor warranty, and parts coverage. A low bid that excludes venting or startup testing may not be the lower final price. Scheduling during a contractor’s less-busy period can sometimes improve availability, although local demand determines whether pricing changes.
Do not choose a smaller furnace solely to cut the equipment cost; incorrect sizing can affect comfort and operating performance. Preserving compatible, safe components and avoiding unneeded accessories is generally more reliable than trimming essential installation work.
Why furnace installation prices differ across U.S. regions
Labor and permit costs often put large metropolitan areas and high-cost coastal markets about 10%-25% above a typical national estimate. Rural areas may be 5%-15% lower when travel and parts access are favorable, but a long-distance service call or limited contractor availability can erase that difference.
For example, a straightforward $5,200 replacement might land around $5,700-$6,500 in an expensive city or $4,400-$5,000 in a lower-cost market. These are comparison ranges, not fixed regional tariffs. Climate affects heating capacity needs, while local rules and the condition of an older home can add permit or code-upgrade expenses.
Use local written bids as the benchmark, and check whether the quoted total includes sales tax, permits, and any required inspection.
How long the installation takes and what can delay it
A standard furnace swap often takes 6-10 hours for a two-person crew when the new unit fits the existing space and vent route. A job involving vent rerouting, condensate drainage, gas-line changes, or duct transitions may take 1-2 days. Labor charges can rise if the furnace is in a tight attic, crawlspace, or finished utility area.
Common added charges include $150-$500 for a condensate pump or new drain arrangement, $200-$800 for gas-line adjustments, and $300-$1,500 for substantial vent modifications. Duct repairs are commonly priced at $200-$1,000 for localized work; replacing extensive ductwork can cost considerably more and should be quoted separately.
Have the installer inspect access, venting, drain location, and gas connections before the final quote is approved.
Three Rheem Classic 90 Plus quote examples
A small, uncomplicated replacement for a roughly 40,000-60,000 BTU furnace might total $3,800-$4,800, including about $1,700-$2,300 for equipment, 8-10 crew hours, basic vent reconnection, permit, and removal.
A typical 60,000-80,000 BTU replacement with a modest vent adjustment could cost $4,900-$6,200. That estimate may include $2,000-$2,800 equipment, 9-12 crew hours, condensate connection, haul-away, and standard startup checks.
A more involved 80,000-100,000 BTU installation with difficult access and a longer vent route may reach $6,500-$8,500. Extra work could include 12-16 crew hours, $600-$1,500 in vent and drainage changes, and additional inspection or code expenses. Illustrative examples only; exact prices depend on model availability and local bids. Use these scenarios to identify which scope items explain a quote above the basic replacement range.