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- Generac #7705 GP15500EFI
- Westinghouse WGen20000
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 | Generac #7705 GP15500EFI | Westinghouse WGen20000 |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | No |
| Running watts | 15500 W | Winner: Winner: 20000 W |
| Starting watts | 19300 W | Winner: Winner: 28000 W |
| Noise (lower limit) | 0 dB | Winner: Winner: 74 dB |
| Weight | Winner: Winner: 420 lbs | 540 lbs |
| Run time @50% load | Winner: Winner: 11 h | Winner: Winner: 11 h |
| Run time @25% load | Not available | 13 h |
| Fuel tank | 14.2 gal | 17.17 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 58.5 x 30.9 x 36.5 | 38 x 35 x 40.4 |
| Electrical | ||
| Voltage (AC) | 120/240 | 120/240 |
| Voltage (DC) | Not available | Not available |
| GFCI outlets | Yes | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | <5% % | 5 % |
| Engine | ||
| Engine | Generac G-Force OVHI 4-stroke | OHV V-Twin, cast iron sleeve |
| Alternator | Not available | Not available |
| Starting system | Electric | Electric |
| Warranty | ||
| Warranty | 3 years | 3 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 15500 W | 20000 W |
| Starting watts | 19300 W | 28000 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 | 11 h | 11 h |
| Run time @25% load | Not available | 13 h |
| Other | ||
| Data center | Not available | Not available |
| Indicators | false | false |
| Compliance | EPA | EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | true | true |
| UPC | 696471083705 | 850011336601 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 15500 | 20000 |
| Starting Watts (Gasoline) | 19300 | 28000 |
| Runtime @ 50% Load (Gasoline) | 11 | 11 |
| Runtime @ 25% Load (Gasoline) | Not available | 13 |
| AC Outlet Types | 2x Duplex 120V 20A (5-20R) GFCI; 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R) | 2x Duplex 120V 20A (5-20R) GFCI; 1x 120V 30A (L5-30R); 2x 120/240V 30A (L14-30R); 2x 120/240V 50A (14-50R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | G-Force OVHI 4-stroke | OHV V-Twin |
| Engine Displacement | 816 | 999 |
| Cylinder Sleeve | Not available | cast iron sleeve |
| Alternator Winding Material | Not available | Copper |
| Engine Oil Type | 10W-30 / SAE 30 | SAE 10W-30 |
| Runtime & fuel system | ||
| Runtime @ 25% Load (Gasoline) | Not available | 13 |
| Runtime @ 50% Load (Gasoline) | 11 | 11 |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection, CO monitoring | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | No |
| Included equipment | ||
| Included Accessories | Oil, battery, and wheel kit | Oil, funnel, tool kit, battery, and wheel kit |
| Warranty & identification | ||
| Commercial Warranty | 3 | 3 |
| Additional specs | ||
| Summary | The Generac #7705 GP15500EFI is a 15,500-watt gasoline generator built for whole-house backup and RV power. Electronic Fuel Injection adjusts fuel delivery based on load, meaning the engine burns only what it needs rather than running at a fixed rate. At this wattage, it can run central air conditioning, a well pump, kitchen appliances, and multiple lighting circuits simultaneously, functioning as a realistic alternative to a permanently installed standby system without the installation cost or natural gas hookup. | The Westinghouse WGen20000TFc is a tri-fuel portable generator capable of producing up to 28,000 peak watts and 20,000 running watts, suitable for home backup and job site power needs. |
- Most PowerfulWestinghouse WGen2000020000W running
- QuietestWestinghouse WGen2000074 dB
- Longest RuntimeGenerac #7705 GP15500EFI11h at 50% load
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Generac #7705 GP15500EFI
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Westinghouse WGen20000
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