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Standby Generator, 11 kW, 29 In H

Price $3,581.00 / each

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  • Item # 21AC90
  • Mfr. Model # 6439
  • UNSPSC # 26111604
  • Catalog Page # 1397
  • Shipping Weight 435.0 lbs.
Country of Origin USA Country of Origin is subject to change.
Note: Product availability is real-time updated and adjusted continuously. The product will be reserved for you when you complete your order. More

Technical Specs

  • Item Standby Generator
  • Engine Cooling Method Air
  • kW 11 LP/10 NG
  • Voltage 120/240
  • Height 29"
  • Width 25"
  • Length 48"
  • Enclosure Material Steel
  • Fuel Type Natural Gas
  • Engine Brand Generac OHVI
  • Engine Size 530cc
  • Engine RPM 3600
  • Amps @ 120/240V, 1 Phase 50
  • NG Consumption @ Half Load 102.4
  • LP Consumption @ Half Load 42.9
  • Hz 60
  • Sound Level dBA 63
  • Warranty 5 yr.
  • Automatic Volts Regulation Yes
  • Battery Included No
  • 12VDC Battery Charger Yes
  • Battery Requirements 525 CCA
  • Engine (Block Heater) Yes
  • Fault Indicator Lights Yes
  • Fuel NPT Pipe Connection Sz. Varies
  • High Temp. Alarm Yes
  • Low Oil Pressure Alarm Yes
  • Min. Gas Pressure @ Generator (In WC) 11 to 14
  • Over Crank Protection Yes
  • Phase 1
  • Power Factor 1
  • Repeat of Exercise Cycle 7 Days
  • Run Time Hour Meter Yes
  • Main Circuit Breaker Yes
  • Over Speed Yes
  • Includes Composite Mounting Pad, Flexible Fuel Line Connector
  • Standards UL2200, CSA, NEMA MG1-22, EGSA
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Compliance and Restrictions

  • Hazardous material - Engines


This standby generator is designed to run quietly, withstand highly corrosive environments, and stand up to severe weather conditions. It provides options for additional features to address individual applications, such as advanced controls for instant monitoring. An RTS Series transfer switch, available separately, is required for use with this generator. Local permits for gas piping, concrete foundation, electrical inspection, and approval are necessary for installation.


Rated 4.9 out of 5 by 115reviewers.
Rated 5 out of 5 by Great product...peace of mind. After two major storms in our area over two years, plus many minor outages on our area over decades, we finally invested ina Generac. While we are actually in progress of getting the transfer switch replaced (under warranty), we've been very happy with it and can now rest knowing we will be covered in any future storms. November 12, 2015
Rated 5 out of 5 by This is an automatic turn on generator which is good for me since I am 70 years old and don't want to have to deal with power outages manually I have a peace of mind having had this Guardian Series Generac whole house generator installed. Thankyou November 10, 2015
Rated 4 out of 5 by This product is what we've been looking for in a Generator. Before purchasing this product we did some research, but found Generac was the one for us. The staff was very knowledgable, courteous and answered all of our questions. On the day of installation Jason, Charlie and Exavier were on time, installation was very quick, as everyone knew exactly what they were doing. The day of the weekly test, it performed beautifully. This gives us such peace of mind. We would highly recommend you to anyone we know that wants a generator. October 6, 2015
Rated 5 out of 5 by This generator is perfect for a rural home. We lived in our home that we built 20 years ago... for 20 winters... and several power outages... and worried about frozen pipes and heat and water unavailability each season.I finally decided the purchase of a Generac generator (11 KW) would be WELL worth it!The unit looks great, is quiet, was installed very professionally, and I CAN SLEEP at night in the winter!!Anyone who lives in a rural setting, who experiences occasional power outages, would be much happier if they invested in one of these units. The piece of mind is priceless. October 3, 2015
Rated 5 out of 5 by Works great! Have had my generator for just over a year now and have had 2 outages. My Generac kicked on without hesitation and kept the lights on for my wife while I was out of town for the wknd.It's comforting knowing that she doesn't have to worry while I'm gone. September 30, 2015
Rated 5 out of 5 by Peace of Mind Our neighbor routinely experiences power outages. I finally got fed up wheeling out our portable gas generator to hook up to our sump pump & refrigerator. Having this 11KW Generac generator gives us peace of mind, & the ability to be away from home without having to worry about power outages. September 29, 2015
Rated 5 out of 5 by Looks good, runs good! When needed, it came through without any interruption. September 11, 2015
Rated 5 out of 5 by A Lifesaver during power outages. Two weeks ago, during a tremendous 11PM thunderstorm, our entire neighborhood lost power for over three hours. We, however, had lights, internet, TV, and basically an entire house of power thanks to Generac. The comfort factor in knowing we don't have to worry about being in the dark again is worth every penny. This is perhaps the greatest improvement we ever made to our house in the 22 years we've been here. Great product! September 11, 2015
  • 2015-11-27 T19:20:37.299-06:00
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There is a 3/4" NPT on inlet. Adapter supplied.

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