Carrier · Infinity 97 (59TN7A) · Model
Carrier Infinity 97 59TN7A 080C21–20
The 59TN7A 080C21–20 is the 80,000 BTU/h, 21-inch-wide Infinity 97: 52,000 BTU/h on low fire, 76,000 BTU/h output on high, 97.0% AFUE upflow, with a 1 HP constant-airflow ECM blower. It suits larger detached houses with 4- to 5-ton cooling.
Rating plate
- Model
- 59TN7A 080C21–20
- Input
- 52,000 – 80,000 BTU/h
- Output
- 50,000 – 76,000 BTU/h
- AFUE
- 97% upflow · 95% down/horiz
- Burner
- Two-stage
- Blower
- ECM, constant airflow
- Fuel
- Natural gas / Propane
- Cabinet
- 35 × 21 × 29.5 in
- Canada
- Available in Canada
This size runs the communicating two-stage system at 52,000 BTU/h input and 50,000 BTU/h output on low fire, and 80,000 BTU/h input and 76,000 BTU/h output on high. Carrier certifies 97.0% AFUE upflow, 96.7% horizontal and 95.0% downflow, with the family's highest horizontal figure tied with the 120,000 BTU/h size.
The 21-inch cabinet and 1 HP communicating constant-airflow blower deliver 1,985 CFM for cooling at 0.5 in. w.c., which is why this width is chosen when a large air conditioner or heat pump shares the ductwork. The 17.5-inch sibling (080C17–16) carries the same gas inputs with a 3/4 HP blower and certifies 96.2% horizontal.
An 80,000 BTU/h input furnace is oversized for many modern Lower Mainland houses. Carrier's product data is explicit that excessive oversizing can shorten furnace and vent life; the size belongs to a heat-loss calculation, not to the old furnace's rating plate.
Specifications
From Carrier's published product data. Input and output are listed separately; AFUE depends on installation position.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Input, high heat | 80,000 BTU/h | |
| Input, low heat | 52,000 BTU/h | |
| Output | ||
| Output capacity, high heat | 76,000 BTU/h | Carrier product data; DOE test procedure, position dependent. |
| Output capacity, low heat | 50,000 BTU/h | |
| Efficiency | ||
| AFUE, upflow | 97 % | |
| AFUE, horizontal | 96.7 % | |
| AFUE, downflow | 95 % | |
| Airflow | ||
| Certified temperature rise, high heat | 40 – 70 °F (22 – 39 °C) | |
| Certified temperature rise, low heat | 25 – 55 °F (14 – 31 °C) | |
| Airflow, high heat @ rated ESP | 1,250 CFM | |
| Airflow, low heat @ rated ESP | 1,100 CFM | |
| Cooling airflow @ 0.5 in. w.c. | 1,985 CFM | |
| Cooling capacity match | 4.5 tons @ 400 CFM/ton; 5.5 tons @ 350 CFM/ton | |
| Blower motor | Communicating variable-speed, constant-airflow (VCA) ECM | Measures and holds the airflow the control requests. |
| Physical | ||
| Cabinet width | 21 in | 533 mm |
| Cabinet depth | 29.5 in | |
| Approximate shipping weight | 171.5 lb | 77.8 kg |
| Cabinet height | 35 in | 889 mm |
| Installation positions | Upflow, downflow, horizontal left, horizontal right | |
| Venting | ||
| Venting | Direct vent (2-pipe), single-pipe, or ventilated combustion air | Maximum equivalent vent length depends on size, pipe diameter and altitude; see installation instructions. |
| Electrical | ||
| Blower motor | 1 HP | |
| Maximum unit amps | 13.1 A | |
| Maximum fuse / breaker | 20 A | |
| Electrical supply | 115 V, 60 Hz, 1 phase (104 – 127 V) | |
| Controls | ||
| Burner staging | Two-stage (low and high fire) | |
| Other | ||
| Burners | 4 | |
| Inducer | Two-speed | |
| Fuel | Natural gas; propane with gas conversion accessory kit | |
Variants
Sizes that share this model page. A variant gets its own page only when it has substantial independent value.
| Size | Input high | Input low | Output high | Output low | AFUE upflow | AFUE down/horiz | Width (in) | Ship wt (lb) | Cooling CFM | Motor HP |
|---|---|---|---|---|---|---|---|---|---|---|
| 080C21–20 | 80,000 | 52,000 | 76,000 | 50,000 | 97 | 95 | 21 | 171.5 | 1985 | 1 |
| 080C17–16 | 80,000 | 52,000 | 77,000 | 50,000 | 97 | 95 | 17.5 | 152.5 | 1350 | 3/4 |
Filters, serial numbers and service parts
Filter
- Field-supplied filter; certified watt data uses Carrier media filter 325531-40
Components this family's service documentation covers
- Hot-surface ignitor
- Flame sensor
- Pressure switches (LPS/HPS)
- Inducer motor
- Condensate trap and drain components
- Constant-airflow ECM blower
- Control board
Service-parts list source: Components documented for service in 59TN7A-01SI.
Warranty coverage, registered or not
- Registered
- 10-year parts and lifetime limited heat exchanger warranty
- Not registered
- Default 5-year parts and 20-year heat exchanger limited warranty
As published by the manufacturer. Source. Conditions and exceptions are in the warranty certificate.
Fault codes this model can show
Best for
- Larger detached homes whose heat-loss calculation supports the capacity
- Communicating Infinity systems with 4.5- to 5.5-ton cooling
- Replacements where a heat-loss calculation confirms the size
Compatible controls
- Communicating Infinity system with Infinity Control, Infinity zoning and Infinity cooling
- 3-digit display showing fault codes and furnace status, with NFC setup via the Carrier service technician app
- RAT and SAT thermistor connections for temperature rise
System integrations
- Infinity air conditioner or heat pump (dual-fuel) with communicating control
- Infinity zoning for single- and multiple-zone systems
- Field-supplied filter or optional media filter cabinet
Warranty, as published
Default 5-year parts limited warranty and 20-year heat exchanger limited warranty; 10-year parts and lifetime limited heat exchanger warranty with timely registration.
Register within 90 days of original installation, except in jurisdictions where warranty benefits cannot be conditioned on registration. Original purchaser/homeowner only; see the warranty certificate. Source
BC Wide can help with registration and warranty enquiries for furnaces it installs or services. Ask about warranty support.
Manuals, codes and service
Documents
Fault codes that apply
- Code 31: high-heat pressure switch (HPS) open or slow to close
- Code 10: rapid flash - L1 polarity fault
- Code 12: W on at power up
- Code 13: limit lockout or ignition lockout
- Code 14: flame-loss lockouts during a heat request
- Code 21: 24 VAC sensed on the gas valve when it shouldn't be
- Code 22: false flame
- Code 23: pressure switch stuck closed
- Code 24: fuse fault
- Code 25: control program and configuration faults
- Code 27: super plug or control program fault
- Code 32: open main pressure switch (LPS)
- Code 43: HPS closed before LPS
- Code 45: control failure
- Code 52: supply-air temperature sensor open or short
- Code 53: return-air temperature sensor open or short
- Code 15: blower RPM lockouts
- Code 41: blower RPM not detected
- Code 51: outdoor-air temperature sensor open or short
- Code 33: a switch has opened in the main limit circuit
- Code 34: ignition fault or flame lost after ignition
BC Wide service
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Guides that reference this model
This catalogue page is reference information for anywhere in Canada. On-site service for this model is available across Greater Vancouver from BC Wide's Burnaby base — see furnace service in Burnaby and all service areas.
Questions people ask
What is the difference between the 080C21–20 and the 080C17–16?
Same gas inputs and the same 97.0% upflow AFUE. The 080C21–20 has the wider 21-inch cabinet, a 1 HP blower with 1,985 CFM of cooling airflow and a 20 A breaker; the 17.5-inch unit uses a 3/4 HP blower and 15 A.
Why does the high-fire output differ from the 59TN6B at the same input?
Carrier's product data lists 76,000 BTU/h high-fire output for the 59TN7A 080C21–20 versus 78,000 BTU/h for the 59TN6B 080C21–20 at the same 80,000 BTU/h input. Outputs follow each family's DOE test results and are copied exactly as published.
Considering the 59TN7A 080C21–20?
Get a published ballpark range for a supply-and-install, then a consultation to confirm sizing from a heat-loss assessment. Equipment-only pricing is not offered on this site.