Williams Furnace Company has been manufacturing heating products for over 100 years. While their products are engineered to last, you may reach a point where the heater should be replaced. If you have an older Williams heater, you can use the chart below to identify the most current replacement model. Not all models listed are direct replacements as heater technology has evolved over the years. Be sure to verify the measurements, fuel type, and specifications to make sure that the new model meets your needs.
| Old Model Number | Replacement Model Number |
|---|---|
| 1403611 | 1403821 |
| 1403612 | 1403822 |
| 2001611 | 2001621A |
| 2001612 | 2001622A |
| 2001612.3 | 2001622A |
| 2203611 | 2203821 |
| 2203612 | 2203822 |
| 2506912 | 2509822 |
| 2509611 | 2509821 |
| 3003611 | 3003821 |
| 3003621 | 3003821 |
| 3003612 | 3003822 |
| 3003622 | 3003822 |
| 3501511 | 3501521A |
| 3501512 | 3501522A |
| 3501512.3 | 3501522A |
| 3501911 | 3501921A |
| 3501912 | 3501922A |
| 3502511.4 | 3502521A |
| 3502512.4 | 3502522A |
| 3502911.4 | 3502921A |
| 3502912.4 | 3502922A |
| 3509611 | 3509821 |
| 3509612 | 3509822 |
| 5001511 | 5001521A |
| 5001512 | 5001522A |
| 5001911 | 5001921A |
| 5001912 | 5001922A |
| 5002511.4 | 5002521A |
| 5002512.3 | 5002522A |
| 5002512.4 | 5002522A |
| 5002911.4 | 5002921A |
| 5002912.4 | 5002922A |
| 5009611 | 5009821 |
| 5009612 | 5009822 |
| 6502511.4 | 6502521A |
| 6202512.3 | 6502522A |
| 6502512.4 | 6502522A |
| 6502911.4 | 6502921A |
| 6502912.3 | 6502922A |
| 6502912.4 | 6502922A |
Williams Comfort Products has manufactured furnaces under the following brand names:
- Dayton
- Grainger
- Debonair
- Dearborn
- Kenmore
- Sears
- Sahara
- Suburban
- Westwood
