Portable Generator, 20,000W, EFI, Electric Start with COsense
SKU: G8939
$4,619.99
Features
Specifications
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From emergency home backup to DIY projects to the jobsite, the Generac GP20000E portable generators provide high wattage, dependable portable power. Equipped with an 817cc engine with Electronic Fuel Injection, these generators deliver optimized fuel efficiency and requires less maintenance. Low THD (<5%) allows you to safely power sensitive elctronics, appliances and tools while onboard COsense® Technology provides powerful protection against hazardous carbon monoxide. These generators also feature electric start (battery included), low-oil pressure shutdown protection, circuit breaker protected outlets and an hour meter with maintenance resets. The included never-flat wheel kit makes transportation easy around the home or jobsite.
- Engine & Performance: Powered by an 817cc OHV Generac engine engineered and built in the USA.
- Electronic Fuel Injection (EFI): Optimizes fuel efficiency and reduces necessary maintenance.
- Clean Power (Low THD): Features low Total Harmonic Distortion (<5%) to safely power sensitive electronics, appliances, and tools.
- COsense® Technology: Onboard carbon monoxide protection that automatically stops the generator, alerts, and protects against hazardous CO buildup.
- Electric Start: Equipped with turn-key ignition for hassle-free startups, with the battery included.
- Safety & Protection Features: Includes low-oil pressure shutdown protection and circuit-breaker-protected outlets.
- Malfunction Indicator: Includes a light on the control panel that flashes when an issue occurs.
- Hour Meter: Tracks maintenance intervals and includes maintenance reset capabilities.
- Portability: Comes with an integrated ergonomic handle and never-flat wheel kit for easy mobility.
- Versatile Outlet Selection: (2) 120V 20A 5-20R GFCI Duplex Outlets (1) 120V 30A Locking Receptacle (NEMA L5-30R) (1) 120/240V 30A Locking Receptacle (NEMA L14-30R) (1) 120/240V 50A Receptacle (NEMA 14-50R)
- Transfer Switch Compatibility: Compatible with the Generac HomeLink™ Manual Transfer Switch.
- Warranty: Includes a 3-year limited residential warranty and a 2-year limited commercial warranty.
| Brand | GENERAC |
|---|---|
| Date Added | Sep 29, 2026 |
| Manufacturer Part Number | 8939 |
| Configuration | 49ST |
| Running Watts | 20,000 W |
| Starting Watts | 22,500 W |
| Engine Type | OHV |
| Engine Displacement | 817cc |
| Starting Method | Electric Start |
| Rated AC Voltage | 120/240 VAC |
| Rated AC Frequency | 60 Hz |
| Rated 120/240 VAC Amperage | 83.3 / 166.6 |
| Fuel Tank Capacity | 14.2 gal (54.0 L) |
| Run Time @ 50% Load | 7.75 Hours |
| Low Oil Pressure Shutdown | Yes |
| COsense Technology | Yes |
| Hour Meter | Yes |
| Dimensions (L x W x H) | 39" x 32.3" x 36.8" |
| Product Weight | 444 lbs (201.4 kg) |
| Residential Warranty | 3-Year Limited |
| Commercial Warranty | 2-Year Limited |