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| Specification | Firman H03655 | Generac #7678 GP3600 |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Dual-Fuel | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | No |
| Running watts | Winner: Winner: 3650 W | 3600 W |
| Starting watts | Winner: Winner: 4550 W | 4500 W |
| Noise (lower limit) | Winner: Winner: 67 dB | 0 dB |
| Weight | 112 lbs | Winner: Winner: 105 lbs |
| Run time @50% load | Winner: Winner: 14 h | 9.3 h |
| Run time @25% load | Not available | Not available |
| Fuel tank | 5 gal | 3.7 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 25.7 x 21.8 x 21.6 | 24 x 22.5 x 21.3 |
| Electrical | ||
| Voltage (AC) | 120V 60 Hz | 120 |
| Voltage (DC) | Not available | Not available |
| GFCI outlets | No | No |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | 25 % | Not available |
| Engine | ||
| Engine | 208 cc OHV 4-stroke, cast iron sleeve | Generac OHV 4-stroke 212 |
| Alternator | Not available | Not available |
| Starting system | Recoil | Recoil |
| Warranty | ||
| Warranty | 3 years | 3 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 3650 W | 3600 W |
| Starting watts | 4550 W | 4500 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 | 9.3 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 | false |
| Compliance | EPA, ANSI/PGMA G300-2023 | CARB |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Floating | Not available |
| UPC | 840876136553 | 696471074581 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 3650 | 3600 |
| Running Watts (Propane) | 3300 | Not available |
| Starting Watts (Gasoline) | 4550 | 4500 |
| Starting Watts (Propane) | 4100 | Not available |
| Runtime @ 50% Load (Gasoline) | 14 | 9.3 |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120V 30A (TT-30R) | 2x Duplex 120V 20A (5-20R) 1x 120V 30A (L5-30R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | 208 cc OHV 4-stroke, cast iron sleeve | OHV 4-stroke |
| Engine Displacement | 208 | 212 |
| Cylinder Sleeve | cast iron sleeve | Not available |
| Engine Oil Type | Not available | 10W-30 / SAE 30 |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 14 | 9.3 |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | No |
| Included equipment | ||
| Mobility Components | Not available | Yes |
| Starting Components | Oil, funnel, tool kit, propane hose, and wheel kit | Oil, funnel, tool kit, and wheel kit |
| Included Accessories | Oil, funnel, tool kit, propane hose, and wheel kit | Oil, funnel, tool kit, and wheel kit |
| Warranty & identification | ||
| Residential Warranty | 3 | Not available |
| Commercial Warranty | 3 | Not available |
| Part Number | Not available | 7678 |
| 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 GP3600 (#7678) is a 3600-watt gasoline generator built for homeowners and job sites needing reliable backup or portable power. Its 4500-watt peak capacity handles starting surges for tools and appliances, while the 3.7-gallon fuel tank delivers 9.3 hours of runtime at half load. Automatic voltage regulation protects sensitive electronics, and a three-year warranty covers ownership support. |