How do I find my furnace model number?
Your Sears gas-fired forced air wall furnace model number for parts lookup is on the rating label attached to the furnace cabinet. For model 867736317, we use that full number to match the correct furnace parts and avoid ordering the wrong component.
Check these common label locations (power off first):
- Outside wall of the furnace cabinet, near the lower front or side panel
- Inside the front access panel on the cabinet frame
- Near the burner compartment opening (on the cabinet, not on the burner)
- On a metal tag or printed sticker that also lists gas type and input BTU
Because this is a gas-fired furnace, take these basic precautions before removing any access cover:
- Set the thermostat to OFF
- Turn off electrical power to the furnace at the switch or breaker
- Let the furnace cool for 10 to 15 minutes
- Do not disturb gas piping or the burner assembly while searching for the label
Copy the information exactly as shown on the label.
| Label item | What to record | Why it matters |
|---|---|---|
| Model number | Full model number (example: 867736317) | Ensures the parts list matches your exact furnace |
| Serial number | Full serial number | Helps identify production variations |
| Fuel and ratings | Gas type, input BTU, voltage | Confirms compatibility for controls and ignition parts |
Many furnace parts look similar but are not interchangeable. Using the exact model number helps us match the correct ignition and safety components, such as a pilot tube 100108370 or a thermocouple, when your furnace has a pilot system.
Last updated: February 2026
How old is my furnace by model number?
You usually cannot determine a furnace’s exact age from the model number alone. For Sears model 867736317 (gas-fired forced air wall furnace), the reliable way is to use the serial number on the rating plate, then match its date code format to the brand’s coding rules; our how to find your appliance model number (and what it means for parts) guide helps you locate the tag.
On most wall furnaces, the rating plate is on the inside cabinet, burner compartment area, or near the gas valve. Look for:
- Serial number (this is the key for age)
- Manufacture date (sometimes printed directly)
- Model number (yours: 867736317)
- BTU input and gas type (natural gas or LP)
Sears-branded heating equipment was often built by an OEM manufacturer, so the serial number format varies. Use these practical checks:
- If the serial includes YYWW or WWYY, that often means year and week of manufacture.
- If it starts with letters, the letters may represent a plant code or month.
- If it includes a clear MMYY block, that often indicates month and year.
| Serial pattern example | What it often means | Example result |
|---|---|---|
YYWWxxxx |
Year, then week | 2310xxxx = week 10 of 2023 |
WWYYxxxx |
Week, then year | 1023xxxx = week 10 of 2023 |
MMYYxxxx |
Month, then year | 0521xxxx = May 2021 |
Knowing the age helps us choose the right repair path: older furnaces are more likely to need ignition and safety parts like a thermocouple or pilot tubing, and age also helps confirm part compatibility before you order.
If your furnace is older and you are seeing pilot or ignition issues, these parts on this model page are common suspects:
- Pilot tube 100108370 (pilot won’t stay lit, weak pilot flame)
- Thermocouple (pilot lights but drops out when you release the knob)
- Burner and gas valve connections (loose fittings or dirty pilot orifice)
Last updated: February 2026
What size furnace do I need for a 2000 square foot house?
For a 2,000 sq. ft. home, most gas furnaces land in the 60,000 to 80,000 BTU/h input range, but the right size depends on climate, insulation, air leakage, and duct design. We recommend sizing with a Manual J load calculation before choosing a furnace.
Use these as a starting point, then confirm with a load calculation.
- Warm climates / tight, well-insulated homes: ~40,000 to 60,000 BTU/h
- Mixed climates / average insulation: ~60,000 to 80,000 BTU/h
- Cold climates / older or leaky homes: ~80,000 to 100,000+ BTU/h
- High ceilings, lots of glass, or poor insulation: size trends higher
- Air sealing and insulation upgrades: often let you size smaller
A 2,000 sq. ft. home can need very different furnace sizes depending on these factors:
- Winter design temperature (your local coldest typical conditions)
- Insulation levels (attic, walls, rim joists)
- Window type and amount of glass (single-pane vs. modern low-E)
- Air leakage (drafts, unsealed penetrations, older construction)
- Duct losses (ducts in attic/crawlspace, leaks, poor returns)
- Desired indoor temperature and comfort goals
Correct sizing improves comfort and efficiency.
- Oversized furnace: short-cycles, uneven temperatures, more noise, more wear
- Undersized furnace: runs constantly in cold weather, struggles to maintain setpoint
| Home and climate profile | Typical BTU/h input range for ~2,000 sq. ft. |
|---|---|
| Tight, upgraded insulation; mild winters | 40,000 to 60,000 |
| Average insulation; moderate winters | 60,000 to 80,000 |
| Older/leaky; cold winters | 80,000 to 100,000+ |
If your Sears model 867736317 is having pilot or burner ignition issues, fixing the ignition system can restore reliable heat without changing furnace size. Common service parts include a pilot tube and thermocouple; see pilot tube 100108370 for the exact replacement listed for this model.
A properly sized furnace heats evenly, runs longer and steadier cycles, and avoids the comfort problems that come from guessing BTU based only on square footage.
Last updated: February 2026
