Furnace Model Number Lookup: Find, Decode, and Use Your HVAC Info

A quick furnace model number lookup can reveal capacity, efficiency, age, warranty status, and parts compatibility. This guide explains how to find the HVAC model and serial number on common U.S. brands, decode what those codes mean, and use them to get the right parts, documentation, and performance data.

What A Furnace Model Number Is—And Why It Matters

A furnace model number is the manufacturer’s exact identifier for a specific configuration. It determines BTU capacity, fuel type, efficiency (AFUE), configuration, and compatible parts. Paired with the serial number, it also helps determine manufacturing date and warranty coverage.

Knowing the correct HVAC model number prevents ordering the wrong igniter, pressure switch, control board, or ECM motor. For modern communicating systems, the precise model number is essential to match controls and firmware. It also supports insurance claims, home sale disclosures, and rebate eligibility.

Where To Find The Furnace Model And Serial Number

Model and serial numbers are printed on the furnace nameplate (data label). Most furnaces have multiple labels; one is the official rating plate used for service and code compliance.

Safety tip: Turn off power at the switch or breaker before removing furnace panels. If you smell gas, stop and call a pro.

How To Perform A Furnace Model Number Lookup

1. Locate the rating plate using the locations above. Photograph the entire label, capturing model, serial, BTU, AFUE, and any barcode.
2. Record the model and serial exactly, including dashes and suffix letters. Small differences matter for parts and firmware.
3. Search the manufacturer site for product literature or parts. Many brands host model-specific IOM (Installation, Operation & Maintenance) manuals and parts lists.
4. Check the AHRI Directory at ahridirectory.org for certified ratings, matched coils/condensers, and reference numbers.
5. Use reputable parts distributors to cross-reference model to OEM parts. Verify part numbers match your exact suffix (e.g., -1A, -3B).
6. Verify serial number for age and warranty on the brand’s warranty lookup page. Registration status may affect coverage.

Pro tip: If the label is torn, try scanning the barcode with a phone. Many labels encode model and serial.

Decoding Model Numbers: Capacity, Configuration, And Efficiency

Model numbers are alphanumeric strings. They typically encode the product family, configuration, input capacity, and sometimes efficiency tier or generation. Exact schemas vary by brand, but these rules of thumb help:

• Capacity: For furnaces, a three-digit number often indicates input BTU in thousands (e.g., 070 ≈ 70,000 BTU, 100 ≈ 100,000 BTU).
• Configuration: Letters can denote upflow (U), downflow (D), horizontal (H), or multi-position. Some brands include airflow (e.g., 036 ≈ 3.0–3.6 tons airflow capacity).
• Efficiency: Suffixes or series codes can imply 80% vs. 90%+ AFUE, single-stage vs. two-stage, and PSC vs. ECM blower.
• Fuel and Venting: Condensing (two-pipe PVC) vs. non-condensing codes appear in many brands’ nomenclature.

Examples (illustrative; verify with brand literature):

• Carrier/Bryant/Payne: 58STA070 or 59SC5A060. The “070/060” denotes BTU input. “59” series often indicates condensing (90%+), “58” non-condensing.
• Trane/American Standard: TUH2B080A9V. “080” ≈ 80,000 BTU, “A9V” may indicate 95%+ AFUE variable-speed ECM.
• Goodman/Amana: GMEC961005CN. “1005” typically ≈ 100,000 BTU input; “96” indicates 96% AFUE series; “EC” denotes ECM.
• Lennox: SL280UH070V36. “070” ≈ 70,000 BTU; “V36” relates to blower/airflow size (3.6 tons nominal).

Always confirm with the manufacturer’s nomenclature chart. Similar-looking models can differ in control boards, igniters, or pressure switches.

Decoding Serial Numbers To Determine Age And Warranty

The serial number encodes manufacturing date. This is critical for warranty eligibility, service bulletins, and estimating life expectancy. Patterns vary by brand and production era.

• YYMM or YYWW: First two digits = year; next two = month or week.
• MMYY: First two = month; next two = year.
• Letter-number combos: A letter may encode month (A=Jan, B=Feb, skipping I) followed by a two-digit year.

Use the table below as a quick-start guide, then verify on the manufacturer’s site. Brands change formats periodically.

Warranty note: Most brands start the limited warranty at the installation date if registered, or at manufacture date if not. Always check registration status on the brand’s warranty lookup page using model and serial.

Brand-Specific Tips For Major U.S. Manufacturers

Carrier, Bryant, Payne

Rating plates are usually inside the blower door or burner compartment. Model numbers like 58/59-series indicate non-condensing vs. condensing. Capacity appears as a three-digit field like 070 or 100. Serial often uses week-year digits in the first four characters.

Find literature and warranty lookup via the brand’s support portal. Product data books include electrical specs, vent tables, and parts lists. Always match suffixes, as -1 vs. -5 can change controls.

Trane, American Standard

Look for a plant letter followed by YYWW in the serial. Models like TUH/ADX indicate gas furnace families, with letters for configuration and ECM. Generation changes may alter pressure switch ratings and igniters.

Use Trane’s OEM parts guides or distributor portals for precise cross-references. When pairing with heat pumps, verify communicating vs. non-communicating controls.

Goodman, Amana, Daikin

Serial numbers usually begin with YYMM. Models often embed AFUE and ECM designation (e.g., GMEC96). Capacity appears near the middle as a four-digit code approximating BTU.

Goodman provides extensive public literature. AHRI certificates are commonly available for furnace/coil/outdoor matches. Confirm pressure switch and board part numbers by full model string.

Lennox

Lennox model strings encode series (e.g., EL/SL), staging, and airflow. Serial numbers often use YYMM early on. Lennox uses many ECM variants (X13, variable-speed); board and motor part numbers must match exactly.

Use Lennox pros’ portals or authorized distributors for parts and bulletins. Pay attention to kit updates superseding older parts.

Rheem, Ruud

Serial codes commonly start with MMYY on furnaces. Models distinguish 80% vs. 90%+ AFUE families. Inducer assemblies and pressure switches are model-year specific.

Rheem’s specification sheets show BTU input/output and temperature rise ranges, useful for diagnostics and commissioning.

York, Johnson Controls

York serial numbers typically use YYWW early in the string. Models may indicate multi-position cabinet and ECM status. Pay close attention to venting category and condensate trap kits on condensing models.

York’s parts lists often include alternate components by production run; use serial ranges to pick the right part.

ICP: Heil, Tempstar, Comfortmaker, Arcoaire, Day & Night

ICP serials commonly use YYWW; older units may use a letter for month. Model numbers align closely with Carrier/Bryant conventions for capacity digits, but parts are ICP-specific.

ICP brand sites host warranty checks and product data. Verify control boards and pressure switches by full model and serial.

Nordyne/Nortek: Maytag, Frigidaire, Tappan, Westinghouse

Serials often begin with YYMM or YYWW. Model prefixes identify brand family and efficiency tier. Use Nortek literature for airflow taps, vent sizing, and OEM parts.

Some Nortek brands emphasize matched systems; consult AHRI for coil/furnace compatibility when adding A/C.

Using Model Numbers For Parts And Compatibility

Accurate parts selection starts with the exact model and serial. Many components vary by capacity, efficiency, or production run.

• Igniters: Silicon nitride vs. silicon carbide. Correct voltage, connector, and mounting are model-specific.
• Flame Sensors: Bent vs. straight rods and bracket lengths vary by series.
• Pressure Switches: Different set points exist for 40k vs. 120k BTU models or for revised heat exchangers.
• Inducer Motors: RPM, wheel, and port configuration differ across sub-models.
• Control Boards: Firmware and wiring terminals change across generations; suffixes matter.
• Blower Motors: PSC, X13, or variable-speed ECM must match amperage, rotation, and programming.
• Filters: Many furnaces specify cabinet size; confirm filter dimensions in the IOM.

Cross-reference process: Find the model’s parts list in the installation/parts manual. Note the OEM part number, then check authorized distributors for current/superseded numbers. Avoid generic “fits most” parts unless the OEM lists them as approved substitutes.

BTU, AFUE, And What Your Model Number Reveals

BTU input is the fuel energy entering the furnace per hour. BTU output is what reaches your home after losses. AFUE is the seasonal efficiency percentage.

• Example: 100,000 BTU input at 95% AFUE delivers about 95,000 BTU output.
• Model capacity fields (e.g., 060, 080, 100) identify input tiers, guiding gas pipe sizing and vent tables.
• Two-stage and modulating models may show better comfort and efficiency via longer, lower-fire cycles.

When pairing with central air, the furnace blower must support the required CFM. Check the product data sheet for blower tables at specified static pressures to ensure proper airflow for 1.5–5 ton systems.

Using The AHRI Directory And Manufacturer Tools

The AHRI Directory is a reliable source for certified performance and equipment matches. It is especially useful when adding or replacing an A/C or heat pump coil with an existing gas furnace.

1. Go to ahridirectory.org.
2. Select the appropriate product section (e.g., Furnaces or Residential Split Systems).
3. Enter the exact model number of the furnace, indoor coil, or outdoor unit.
4. Review the AHRI Certified Reference Number and matched components list.
5. Save or print the certificate for rebates, code compliance, or utility incentives.

Note: For gas-only furnaces without new A/C equipment, AHRI listings may be limited to furnace performance details. Manufacturer portals often provide more detailed parts and wiring documentation.

If The Label Is Missing Or Unreadable

Even if the rating plate is damaged, there are ways to recover the information.

• Check service records: Invoices or maintenance stickers often list model and serial.
• Look inside the blower compartment: Secondary labels or barcodes may remain intact on the cabinet.
• Inspect the control board: The board’s OEM part number can lead to the model via parts databases.
• Ask the installer: Contractors keep job records with model/serial for permits and warranty.
• Check permits: Local building departments may have equipment details in permit files.
• Use homeowner portals: Some communicating systems expose model info in the thermostat or app.

If all else fails, take clear photos and contact manufacturer support. Do not guess at parts; mismatched components can be unsafe.

Safety, Code, And Warranty Considerations

Furnaces involve gas, high voltage, and combustion byproducts. Always shut off power before opening panels. If there is any sign of gas odor, soot, or melted wiring, stop and call a licensed HVAC technician.

• Combustion safety: Maintain proper venting and combustion air. Replace compromised heat exchangers immediately.
• Carbon monoxide: Install CO detectors on each level of the home; test regularly.
• Code compliance: Model numbers tie to installation clearances, vent lengths, and gas line sizing. Follow the IOM and local code.
• Warranty: Many brands require registration within a set period after installation. Keep proof of install date.

Common Pitfalls During Furnace Model Number Lookup

Several mistakes can lead to wrong parts or delays:

• Using the wrong label: Accessory or blower labels are not the official furnace model.
• Missing suffixes: A trailing letter/number can change critical parts.
• Assuming capacity: Do not infer BTU only from room size. Use the model’s capacity field and data sheet.
• Ignoring serial ranges: Parts may differ before/after a certain serial number cutoff.
• Mixing brand families: ICP parts are not always interchangeable with Carrier-branded equipment.

Quick Reference: Finding And Using Your Numbers

• Find: Inside blower door or burner compartment; photograph the whole plate.
• Decode: Identify capacity digits (e.g., 070, 080, 100) and AFUE series.
• Verify age: Read the serial code (YYMM, YYWW, or MMYY) and confirm on the brand site.
• Check AHRI: Confirm matched system components and certified ratings.
• Order parts: Use OEM part numbers from the model’s parts list; match suffix and serial range.

Frequently Asked Questions About Furnace Model Number Lookup

Where is the furnace model number located? Usually on the rating plate inside the blower door or burner compartment. Some furnaces have an exterior side label.

How do I tell the age of my furnace from the serial number? Most brands encode year and week or month in the first four characters. Cross-check on the manufacturer’s warranty or support page.

What if my serial number uses letters? Some brands use letters for month codes (A=Jan). Refer to the brand’s serial guide to interpret the code correctly.

Can I use a universal part if my model is discontinued? Sometimes, but use the OEM-approved substitute listed in parts literature. The wrong part can be unsafe.

Will model number lookup help with rebates? Yes. Use the model number to pull an AHRI certificate showing AFUE and matched components, which many utilities require.

Is AFUE listed in the model number? Not always directly. The series name or suffix may imply efficiency, but the rating plate and product data sheet list AFUE explicitly.

Does the furnace model number determine filter size? Not always. Filter size depends on the return-air cabinet or media cabinet. Check the installation manual or measure the slot.

How do I find compatible A/C equipment? Use the furnace model with the indoor coil and outdoor unit model at ahridirectory.org to confirm matched system ratings.

Can I decode a worn label? Try enhancing photos, scanning barcodes, or referencing parts lists via the control board number. If needed, contact the manufacturer with photos.

Useful Manufacturer And Resource Links

• AHRI Directory – Certified performance and matched system listings.
• Carrier Residential Support – Product literature and warranty lookup.
• Trane Residential Resources – Manuals and registration.
• Goodman Support – Literature and warranty info.
• Lennox Support – Manuals and parts catalogs.
• Rheem Residential – Product support.
• York Support – Product documents.
• ICP Brands – Heil, Tempstar, Comfortmaker resources.
• Nortek Global HVAC – Maytag, Frigidaire, Tappan info.

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Meta: Learn how to find and decode your furnace model and serial numbers. Use this furnace model number lookup guide to verify BTU, AFUE, age, warranty, and parts compatibility for Carrier, Trane, Goodman, Lennox, Rheem, York, and more.