Guardian QuietSource Liquid Cooled 22KW - 48KW Standyby Generators

Guardian QuietSource 22 – 48 kW Standby Generators

22 - 48 Quietsource

GUARDIAN QuietSource generators are ideal for applications that require ultra-quiet operation and exceptional fuel economy. With larger and more powerful liquid-cooled engines that run at 1800 RPM under full load and our exclusive Whisper-Test feature, QuietSource generators are the quietest in the industry. In addition, these larger engines achieve greater power output with less effort, resulting in significantly reduced fuel consumption both during exercise and under full load.

QuietSource models also come standard with all aluminum enclosures for superior protection against salt air and other corrosive environments. Aluminum enclosures, combined with Guardian’s superior paint system, keep QuietSource generators looking like new for years… even in coastal areas.

  • High Displacement, Low Speed, Liquid-Cooled Engine: Provides ultra-quiet operation and exceptional fuel economy
  • Gray, Aluminum Enclosure: Superior corrosion protection for coastal communities
  • Whisper-Test: Low speed exercise feature makes QuietSource the quietest generators on the market
  • Superior Paint: Tough, textured powder coat paint finish for unmatched durability and all weather protection
  • UL Listed: For safety and certified power ratings
  • Clean Burning Fuel: Natural gas or LPV
Model Number 5638 5639 5420 5640 5421 5642
Rated Power (LP / NG) 22/22 27/25 35/35 36/35 45/42 48/45
Rated Amps @ 60 Hz          
240 V, 1Ø 92/92 113/104 145.8/145.8 150/146 187.5/179.2 200/188
Surge Watts - 240V, 1 Ø 37,920 48,960 54,000   77,040  
Surge Amps 158 204 225   321  
Engine 2.4L/4 Cyl. 2.4L/4 Cyl. 4.2L/V-6 2.4L/4 Cyl. 4.2L/V-6 4.2L/V-6
Alternator RPM 1800 1800 1800 1800 1800 1800
Enclosure Aluminum Aluminum Aluminum Aluminum Aluminum Aluminum
Whisper Test Yes Yes Yes Yes Yes Yes
Sound Level (dBA @ exercise) 61 62 60 58 60 60
(dBA @ normal operation) 70 75 65 64 65 65
Dimensions (L” x W” x H”) 62.2×29x33.5 62×29x34 77×34x45 77×34x45 77×34x45 77×34x45
Compatible Transfer Switches RTS RTS RTS RTS RTS RTS
Unit Weight (lbs.) 895 1255 1683 TBD 1703 1740
Full Spec Sheet Spec Sheet Spec Sheet Spec Sheet Spec Sheet Spec Sheet Spec Sheet