FIRMAN W03663OF 4500W Open Frame Inverter
A gas open-frame inverter generator rated at 3,650 running and 4,500 starting watts, with a 6-gallon tank and up to 23 hours of runtime at 25% load. It shuts itself off if carbon monoxide builds up and can run in parallel with a second unit.
- Running watts
- 3,650 W
- Starting / surge watts
- 4,500 W
- Fuel
- gasoline
- Best for
- RV trips and home backup for a fridge, lights and electronics, with clean power.
- Not for
- Whole-home backup or 240V appliances.
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Specifications
| Running watts | 3,650 W |
|---|---|
| Starting / surge watts | 4,500 W |
| Fuel | gasoline |
| Inverter (clean power) | Yes |
| Parallel capable | Yes |
| Runtime at 25% load | 23 h |
|---|---|
| Fuel tank | 6 gal |
| Weight | 116 lb |
|---|
| CO safety shutoff | Yes |
|---|---|
| Standard warranty | 3 years |
Checked 29 October 2026. Sources: firmanpowerequipment.com.