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- Firman H03655
- Generac #8917 GP18000EFI
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 H03655 | Generac #8917 GP18000EFI |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Dual-Fuel | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | Yes |
| Running watts | 3650 W | Winner: Winner: 18000 W |
| Starting watts | 4550 W | Winner: Winner: 22500 W |
| Noise (lower limit) | Winner: Winner: 67 dB | 0 dB |
| Weight | Winner: Winner: 112 lbs | 442.8 lbs |
| Run time @50% load | Winner: Winner: 14 h | 9 h |
| Run time @25% load | Not available | Not available |
| Fuel tank | 5 gal | 14.2 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 25.7 x 21.8 x 21.6 | 58.5 x 30.9 x 36.5 |
| Electrical | ||
| Voltage (AC) | 120V 60 Hz | 120/240 |
| Voltage (DC) | Not available | Not available |
| GFCI outlets | No | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | 25 % | <5% % |
| Engine | ||
| Engine | 208 cc OHV 4-stroke, cast iron sleeve | Generac G-Force OVHI 4-stroke |
| Alternator | Not available | Not available |
| Starting system | Recoil | Electric |
| Warranty | ||
| Warranty | 3 years | 3 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 3650 W | 18000 W |
| Starting watts | 4550 W | 22500 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 | 14 h | 9 h |
| Run time @25% load | Not available | Not available |
| Propane | Not available | Not available |
| Running watts | 3300 W | Not available |
| Starting watts | 4100 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 | Not available | Not available |
| Run time @25% load | Not available | Not available |
| Other | ||
| Data center | Not available | Not available |
| Indicators | false | true |
| Compliance | EPA, ANSI/PGMA G300-2023 | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Floating | Bonded to Frame |
| UPC | 840876136553 | 696471101324 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 3650 | 18000 |
| Running Watts (Propane) | 3300 | Not available |
| Starting Watts (Gasoline) | 4550 | 22500 |
| Starting Watts (Propane) | 4100 | Not available |
| Runtime @ 50% Load (Gasoline) | 14 | 9 |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120V 30A (TT-30R) | 120/240V 50A (NEMA 14-50R), 120V 20A GFCI Duplex (NEMA 5-20R), 120V 30A Locking (NEMA L5-30R), 120/240V 30A Locking (NEMA L14-30R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | 208 cc OHV 4-stroke, cast iron sleeve | Generac G-Force OVHI 4-stroke |
| Engine Displacement | 208 | 816 |
| Cylinder Sleeve | cast iron sleeve | Not available |
| Engine Oil Type | Not available | 10W-30 / SAE30 |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 14 | 9 |
| Controls & display | ||
| Display Type | Not available | Hour Meter |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Not available |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | Yes |
| Included equipment | ||
| Mobility Components | Not available | 12" Never-flat Wheels, Folding Locking Handle |
| Starting Components | Oil, funnel, tool kit, propane hose, and wheel kit | Electric Start, Battery Included |
| Included Accessories | Oil, funnel, tool kit, propane hose, and wheel kit | Battery included |
| Warranty & identification | ||
| Residential Warranty | 3 | 3 |
| Commercial Warranty | 3 | 2 |
| Part Number | Not available | 8917-0 |
| Additional specs | ||
| Summary | The Firman H03655 is a 3,650-watt dual-fuel generator built around a 208 cc OHV 4-stroke engine with a cast iron sleeve. Running on gasoline, it delivers 4,550 starting watts and 3,650 running watts. Switch to propane and output drops to 4,100 starting watts and 3,300 running watts. This power level runs a refrigerator, microwave, window air conditioner, or multiple power tools simultaneously. The dual-fuel flexibility means you can operate on whichever fuel is available, a practical advantage during extended outages or when propane storage is more convenient than gasoline.
At 67 dB at quarter load, the H03655 operates quietly enough for residential neighborhoods without disturbing neighbors. The 5-gallon tank delivers 14 hours of runtime at 50 percent load on gasoline, translating to roughly one full day of moderate use before refueling. The RV-ready configuration and included wheel kit position this unit as a go-anywhere power source for camping, job sites, and home backup scenarios. | The Generac GP18000EFI is an 18,000 watt gasoline generator built for whole house backup and demanding job sites. With 22,500 peak watts, it can run central air conditioning, well pumps, electric ranges, and full household loads simultaneously. This is a stationary power solution for users who need utility replacement capacity. |
- Most PowerfulGenerac #8917 GP18000EFI18000W running
- QuietestFirman H0365567 dB
- Longest RuntimeFirman H0365514h at 50% load
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Firman H03655
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Generac #8917 GP18000EFI
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