Head to head
Generac GP6500 COsense vs Firman T07571 Tri-Fuel
Generac · Portable Generator
Generac GP6500 COsense
~$999
6,500 W / 8,125 W surge · up to furnace blower, sump pump or a window AC
Firman · Portable Generator
Firman T07571 Tri-Fuel
~$999
7,500 W / 9,400 W surge · up to well pump or a small central AC
Quick takeThe Firman T07571 Tri-Fuel puts out more sustained power (7,500 W).
| Spec | Generac GP6500 COsense | Firman T07571 Tri-Fuel |
|---|---|---|
| Approx. price | ~$999 | ~$999 |
| Type | Portable Generator | Portable Generator |
| Fuel | Gasoline | Tri Fuel (Gas/LP/NG) |
| Running / output watts | 6,500 W | 7,500 W |
| Starting / surge watts | 8,125 W | 9,400 W |
| Battery capacity | — | — |
| Expandable to | — | — |
| Noise | — | 74 dB |
| Runtime | 16.5 hrs at 25% load, 11.5 hrs at 50% on 7.9 gal | up to 12 hrs @ 25% load (8 gal gas); unlimited on NG hookup |
| Outlets | 2x 120V 20A GFCI (5-20R duplex), 1x 120/240V 30A (L14-30R) | 1x 120V 20A GFCI duplex (5-20R), 1x 120V 30A (L5-30R), 1x 120/240V 30A (L14-30R), 1x 120/240V 50A (14-50R) |
| Fuel tank | 7.9 gal | 8 gal |
| Weight | 182 lbs | 213 lbs |
| Transfer-switch ready | Yes | Yes |
| Warranty | 3-year residential, 1-year commercial | 3-year limited |
Highlighted cell is the better figure for that row.
Owner pros and cons
Generac GP6500 COsense
- +L14-30R outlet feeds a 30-amp transfer switch
- +PowerRush gives 8,125 W starting capacity for motors
- +Electric start with a battery included
- +20-foot multi-outlet cord and hour meter included
- +Generac dealer and parts network is the largest in the US
- −No noise figure published on the page or the spec sheet
- −Gasoline only, with the usual stale-fuel storage problem
- −182 lbs limits who can move it alone
- −Neutral is bonded to ground, which matters when wiring some transfer setups
- −Rated a step below the 7,500 W class that most whole-house loads call for
Firman T07571 Tri-Fuel
- +Cheapest credible tri-fuel path to NG-powered backup
- +LP and NG hoses included — no accessory hunt
- +50A 14-50R plus 30A outlets cover any transfer setup
- +Electric start with battery included
- +3-year warranty on paper, generous Costco returns in practice
- +Solid 213-lb frame with never-flat wheels
- −5,500W on natural gas is a steep derate
- −74 dB open-frame noise
- −Output sags at higher loads on NG in owner reports
- −Manual fuel-selection procedure trips up first-timers