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Generac EXPRESS SERIES Generator Set

The Generac EXPRESS SERIES is a 25 kW Natural Gas or L.P. Vapor standby generator set powered by a Generac MMC 4G15 engine. It is available at 120/240 V, 1-phase, 60 Hz and rated 104 A. It holds about 3.8 L (1.0 gal) of oil and 2 L (0.5 gal) of coolant, with a maximum ambient rating of 50 °C. The set weighs about 860 kg (1896 lb).

25 kW
Standby
1.5 L
Displacement
3.8 L
Oil capacity
1
Document types

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Specifications

FuelNatural Gas or L.P. Vapor
Frequency60.0 Hz
Standby power25 kW
ControllerHome standby control console with overcrank, overspeed, low oil pressure and high coolant temperature shutdowns
Oil capacity3.8 L
Voltage options120/240 V
Phase1
Rated current104 A
Power factor1.0
Battery quantity1
Coolant capacity2 L
Max ambient50 °C
Dry weight860 kg

Engine

Generac MMC 4G15
Oil capacity3.8 L
Coolant capacity0.9 L
Displacement1.5 L
AspirationNaturally Aspirated
Rated speed3600 rpm

Maintenance & consumables

for the Generac MMC 4G15
ItemSpecCapacityPart #Interval
Air filterAir cleaner find
Fuel filterDown draft carburetor with secondary fuel regulator for natural gas or L.P. vapor systems, hot water vaporizer for L.P. liquid withdrawal systems find
Oil filterFull flow, cartridge oil filter find
BeltMainline circuit breaker find
CoolantCooling system with coolant capacity of 2 US gallons, radiator capacity of 1.75 US gallons, and coolant flow rate of 10.6 US gallons per minute
OilGear type oil pump, full flow, cartridge oil filter3.8 L

Common questions

What is the power rating of the Generac EXPRESS SERIES?

The Generac EXPRESS SERIES is rated 25 kW standby.

What engine does the Generac EXPRESS SERIES use?

The Generac EXPRESS SERIES is powered by the Generac MMC 4G15 engine.

What fuel does the Generac EXPRESS SERIES use?

The Generac EXPRESS SERIES runs on Natural Gas or L.P. Vapor.

What is the oil capacity of the Generac EXPRESS SERIES?

The Generac MMC 4G15 engine in the Generac EXPRESS SERIES has an oil capacity of 3.8 liters.

Fuel consumption

RatingLoadL/hgal/h
Prime442.0
Standby183.0

Available documents

Spec sheet — 01683700EW (Generac)