Cummins Diesel Standby Generator- RS20A | Absolute Generators

Cummins Diesel Standby Generator- RS20A | Absolute Generators

Cummins Home Standby Generator - RS20A, 18 kW-20 kW, 120/240 Volt, Air-Cooled, 3600 RPM

Model: RS20A

Status: Available

List Price: $4,200.00
Sale Price: $4,049.00

* Required Fields


Bi-Fuel: LP & NG




Home Standby


Automatic (With ATS)

Watts (LP)


Watts (NG)



All 50 States

Cummins RS Air-Cooled Series Home Standby Generator – RS20A, 20 kW, 120-240 Volt, Single Phase

  • QSJ999G, naturally aspirated, air-cooled, V-twin, overhead valve engine for reliable power
  • Single fuel – natural gas or propane vapor
  • Monitor your generator from almost anywhere with a computer, smart phone, or tablet
  • Built in display under the hood
  • Aluminum enclosure with galvanized steel interior 
  • Sound level is a quiet 65 dB(A)
  • Flexible Exercise modes includes Cummins patented "crank only" mode that allows the generator to crank the engine and run diagnostics without starting the engine.
  • Industry leading motor starting capabilities and can easily start and run 2 each 5 ton A/C units under full pre-load.
  • UL, EPA emissions, and CSA 22.2 and B149-2 compliant

The Cummins RS20A is an aesthetically pleasing quiet generator with 20 kW of power.  This generator is fully automatic (with the optional transfer switch) and can easily start and run a 5 ton air conditioning unit under full pre-load, Cummins backs this generator with a strong  5 year or 2000 hour, limited warranty.


Manufacturer Cummins
Model Number RS20A
Alternate Model Number A054E399
Generator Grade Emergency
Generator Style Home Standby
Generator Operation Fully Automatic (With Automatic Transfer Switch)

Engine Details

Engine/Motor Brand Cummins
Fuel Type Bi-Fuel: LP & NG
Starting System Automatic (With ATS)
Battery For Electric Start Add @ Checkout
Engine/Motor Type Air-Cooled, V-Twin, OHV
Displacement 999 cc
Engine RPM 3600 RPM
LP Consumption 50% Ld 68 Cubic Feet/Hour
LP Consumption 100% Ld 116 Cubic Feet/Hour
NG Consumption 50% Ld 205 Cubic Feet/Hour
NG BTU/Hour @ 50% Ld 205000
NG Consumption 100% Ld 300 Cubic Feet/Hour
NG BTU/Hour @ 100% Ld 300000
Enclosure Aluminum
Low Oil Shutdown/Alert Yes
Oil Cooler Yes
Lubrication System Automotive-Style
Engine Governor Electronic
Operational Volume (dB) 65.0
Overload Protection Yes
Exerciser Flexible


Fuel Supply Hose Included, 1', Flexible
Cold Weather Kit Included
Maintenance Kit Add @ Checkout
Mounting Pad Add @ Checkout


Warranty 5 Year Or 2000 Hour (limited)


Built In United States

Other Information

Weight (Lbs.) 540
Unit Dimensions 53.0"Lx43.0"Wx34.7"H
Agency Compliance CARB (California), EPA, UL
California Destination-Operators-Buyers Warning Click Here For California Proposition 65 Warning

Generator Details

Watts (LP Standby) 20,000
Watts (NG Standby) 18,000
Voltage 120, 240
Rated Amps @ Min Volt 166.6
Rated Amps @ Min Volts (NG) 150.0
Rated Amps @ Max Volt 83.3
Rated Amps @ Max Volt (NG) 75.0
Frequency 60 Hz
Phase Single-Phase
Poles 2
A/C Ton Rating 2 @ 5 Tons
Voltage Regulation +/-1.25%
Frequency Regulation 0% No Load To Full Load
Total Harmonic Distortion Less Than 5%
Circuit Breakers 100 Amp
Continuous Battery Charge Yes
Control Panel Display Yes, Wired In-Home LCD Display, Maintenance Reminder, Complete Gen-Set Monitoring And Protection, Proprietary Eletronic Control
Load Management Automatic Load Management @ Generator

Transfer Switch

Transfer Switch Add @ Checkout

No Accessories for this product.

Free Freight Included With Every Order

  • Shipments < 150 lbs. Will Be By FedEx Or UPS To Garage Or Front Door
  • Shipments > 150 lbs. Will Be By Extes-Express, RL Carriers, Or Other To Curbside At Truck Deck Height
  • Free Standard Freight To Lower 48 States
  • Free Standard Freight Does Not Include Service To Alaska, Hawaii, Or Destinations Outside The United States. Contact Us To Make Other Accommodations For Shipments Outside The Lower 48 States.
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