Compare Generators Side-by-Side
Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.
- Firman H08051
- NorthStar c15000s
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
| Specification | Firman H08051 | NorthStar c15000s |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Dual-Fuel | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | No |
| Running watts | 8000 W | Winner: Winner: 13500 W |
| Starting watts | 10000 W | Winner: Winner: 15000 W |
| Noise (lower limit) | 74 dB | Winner: Winner: 73 dB |
| Weight | Winner: Winner: 212 lbs | 390 lbs |
| Run time @50% load | Winner: Winner: 12 h | 10.6 h |
| Run time @25% load | Not available | Not available |
| Fuel tank | 8 gal | 12 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 30.2 x 27.5 x 26.3 | 43 x 36 x 35 |
| Electrical | ||
| Voltage (AC) | 120/240 | 120/240V 60 Hz |
| Voltage (DC) | Not available | Not available |
| GFCI outlets | Yes | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | 25 % | <5% % |
| Engine | ||
| Engine | Firman Max-Pro Series OHV 4-stroke, cast iron sleeve | 688 cc Honda GX690 OHV V-Twin |
| Alternator | Not available | Not available |
| Starting system | Recoil, Electric | Electric |
| Warranty | ||
| Warranty | 3 years | 4 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 8000 W | 13500 W |
| Starting watts | 10000 W | 15000 W |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | 12 h | 10.6 h |
| Run time @25% load | Not available | Not available |
| Propane | Not available | Not available |
| Running watts | 7250 W | Not available |
| Starting watts | 9050 W | Not available |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | 5 h | Not available |
| Run time @25% load | Not available | Not available |
| Other | ||
| Data center | Not available | Not available |
| Indicators | false | false |
| Compliance | CARB, EPA | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Bonded to frame | true |
| UPC | 840876180518 | 840321737861 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 8000 | 13500 |
| Running Watts (Propane) | 7250 | Not available |
| Starting Watts (Gasoline) | 10000 | 15000 |
| Starting Watts (Propane) | 9050 | Not available |
| Runtime @ 50% Load (Gasoline) | 12 | 10.6 |
| Runtime @ 50% Load (Propane) | 5 | Not available |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R) | 3x Duplex 120V 20A (5-20R) GFCI1x 120V 30A (L5-30R)1x 120/240V 30A (L14-30R)1x 120/240V 60A (14-60R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | OHV 4-stroke | Honda GX690 OHV V-Twin |
| Engine Displacement | 439 | 688 |
| Cylinder Sleeve | Cast iron | Not available |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 12 | 10.6 |
| Runtime @ 50% Load (Propane) | 5 | Not available |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | No | Yes |
| Included equipment | ||
| Mobility Components | Wheel kit | Not available |
| Starting Components | Recoil, Electric | Not available |
| Fuel Connection Components | Propane hose | Not available |
| Included Accessories | Oil, funnel, tool kit, propane hose, battery, and wheel kit | Funnel, battery, and wheel kit |
| Warranty & identification | ||
| Commercial Warranty | 3 | 4 |
| Additional specs | ||
| Summary | The Firman H08051 is an 8,000-watt dual-fuel generator built to power job sites, homes during outages, and RV setups. Running on gasoline, it delivers 8,000 watts continuously and 10,000 watts at startup, enough to run a refrigerator, microwave, and multiple power tools at once. Switch to propane and the output drops to 7,250 watts running and 9,050 watts starting, a trade-off for fuel flexibility and longer shelf life. The 439cc cast-iron engine is engineered for durability in commercial and residential use. At 212 pounds, this is a stationary or semi-portable unit, not a grab-and-go machine. | The NorthStar c15000s is a commercial-grade portable generator powered by a Honda GX690 OHV engine, delivering 15,000 surge watts and 13,500 rated watts. It features Quiet Armor Technology for reduced noise, a built-in battery charger/maintainer, and carbon monoxide detection with automatic shutdown for enhanced safety. |
- Most PowerfulNorthStar c15000s13500W running
- QuietestNorthStar c15000s73 dB
- Longest RuntimeFirman H0805112h at 50% load
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Firman H08051
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