FIRMAN WT12579 12500W Tri Fuel Inverter
A tri-fuel inverter generator rated at 10,000 running and 12,500 starting watts, with a 7.1-gallon tank and up to 16 hours of runtime at 25% load. It shuts itself off if carbon monoxide builds up, has 120/240V output for a transfer switch and can run in parallel with a second unit. FIRMAN rates it at 69 dB(A).
- Running watts
- 10,000 W
- Starting / surge watts
- 12,500 W
- Fuel
- gasoline, propane, natural gas
- Best for
- Home backup through a transfer switch, including bigger loads, with clean power for electronics.
- Not for
- Indoor or garage use. Like every fuel-burning generator it must run outdoors, away from windows.
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Specifications
| Running watts | 10,000 W |
|---|---|
| Starting / surge watts | 12,500 W |
| Fuel | gasoline, propane, natural gas |
| Inverter (clean power) | Yes |
| Parallel capable | Yes |
| Runtime at 25% load | 16 h |
|---|---|
| Fuel tank | 7.1 gal |
| Outlets | 120V 5-20R, USB |
|---|
| Noise | 69 dB(A) |
|---|
| CO safety shutoff | Yes |
|---|
Checked 29 October 2026. Sources: firmanpowerequipment.com.