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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 USACountry 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

  • ItemStandby Generator
  • Engine Cooling MethodAir
  • kW11 LP/10 NG
  • Voltage120/240
  • Height29"
  • Width25"
  • Length48"
  • Enclosure MaterialSteel
  • Fuel TypeNatural Gas
  • Engine BrandGenerac OHVI
  • Engine Size530cc
  • Engine RPM3600
  • Amps @ 120/240V, 1 Phase50
  • NG Consumption @ Half Load102.4
  • LP Consumption @ Half Load42.9
  • Hz60
  • Sound Level dBA63
  • Warranty5 yr.
  • Automatic Volts RegulationYes
  • Battery IncludedNo
  • 12VDC Battery ChargerYes
  • Battery Requirements525 CCA
  • Engine (Block Heater)Yes
  • Fault Indicator LightsYes
  • Fuel NPT Pipe Connection Sz.Varies
  • High Temp. AlarmYes
  • Low Oil Pressure AlarmYes
  • Min. Gas Pressure @ Generator (In WC)11 to 14
  • Over Crank ProtectionYes
  • Phase1
  • Power Factor1
  • Repeat of Exercise Cycle7 Days
  • Run Time Hour MeterYes
  • Main Circuit BreakerYes
  • Over SpeedYes
  • IncludesComposite Mounting Pad, Flexible Fuel Line Connector
  • StandardsUL2200, CSA, NEMA MG1-22, EGSA
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Compliance and Restrictions

  • Hazardous material - Engines



Rated 4.9 out of 5 by 110reviewers.
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
Rated 5 out of 5 by Its all about being prepared. We purchased a generator last year. we have only had a couple of times that we needed to use it, but when the time comes and your generator kicks in you know you made the right decision. Its just like the power is still on.We liked the peace of mind so much that this year we purchased one for our son.All my neighbors have been asking questions and I have been happy to tell them what I know. I recommend the generac generator. September 10, 2015
Rated 5 out of 5 by Love it so far We had our first power failure about three weeks ago and it was the first real test for my generator and it passed with flying colors. It was a little noisy but at least I had lights and air conditioning for the four hours we were out. Two of my neighbors came over to at least be able to watch TV and have a cold one or two and it was fun to be the only guy on the block with lights. Glad I invested in this and I hope it lasts a good long time as I'm sure it will. It looks pretty good too on the side of my house and not an eyesore. You'll be glad you invested in one of these I can assure you. Ken at the Jersey Shore. September 10, 2015
Rated 5 out of 5 by 11kw generator I purchased the 11kw generator to run a 1500sq ft house and my garage during a power outage. We have several power outages in this area throughout the year and a generator was a must-have item on my list for my new home. My generator transfers flawlessly in seven seconds when the power goes out. It is so unnoticeable that I did not even know my power was out one day until I went outside and heard the generator running! I have propane that runs my heat, on-demand water heater, stove, and dryer. I still need electricity to run all the propane items except the stove. I was very worried about a power outage during the winter because I have no backup heat. The generator has come on numerous times since purchased one year ago and life went on with no problems. I LOVE THIS GENERATOR! September 10, 2015
Rated 5 out of 5 by Generac Guardian 11kW wouldn't be without it! having had portable generators in the past and what it takes to get them out, set up and running, I really enjoy the peace of mind I now have with having my Generac stand-by generator in place at always at the ready! Makes me almost want the power to go out, just kidding. My wife works from home doing telephonic nursing, and she needs to have electric power as well as internet to be able to do her job from her home office. We went with the 11,000 watt unit, so we were able to do a full transfer of our entire panel box. We can now rest assured as far as electricity goes, we should never be without it. For reliability, ease of use, dependability, and sheer quietness of the machine when it runs, I would never want to live without one now! I am very satisfied with not only my purchase, but the reliability I have read about and heard from friends and neighbors who already had a Generac in place when I was thinking about getting a unit for myself! The appearance of the machine doesn't take away at all from my landscaping, which also is a plus in my book! Thank you Generac for easing my mind when it comes to power outages. I am constantly spreading the word about your product to friends, family members and co-workers. September 10, 2015
Rated 5 out of 5 by Why did it take me so long to own on these Genrators I purchased my 11w Generac Generator last year 2014 and I'm so happy with my decision. While I haven't had a major power outage yet. It's really nice to know it's there when the power go out for an hour or so because there's no interruptions. It's a great investment! Nettie September 10, 2015
Rated 5 out of 5 by My generac 11KW with SE rated whole house switch review I had been looking for a generator like this for some time, found out they were on sale so went up to my local store and placed an order as this was not in stock. What is nice about this generator configuration is that the switch goes in between the meter can and your load center instead of putting up the sub panel with breakers. What this means is you do not have to pick and choose which circuits you want to keep and which ones you can lose. As with all generators however, you are limited on what you can run at one time based on the amp draw of your load compared to how many amps your generator will put out.Installation: I opted to do the installation myself, I do not recommend this for the average purchaser as it was rather involved and quite frankly, could kill you if you don't know what you're doing. Be sure to read all instructions that come with generator and switch as recommended clearances should be adhered to as well as recommendations for pipe size and lengths of run. Upon inspecting the area I wanted to set the generator, I went with a poured concrete pad for my site location, I prefer concrete over the gravel bed option. After delivery, I had a friend help set generator on pad as this is about 400lbs. I sized the gas line as required and put in appropriate shut off. I made the electrical connections as required by code, this is the lengthy part of the process and is also the one that can kill you dead. I made sure to use arc flash gear as you expose yourself to live power directly from the utility while doing it, even though your meter is pulled. Based on my location, I purchased the optional cold weather kit. Installation of that was a breeze, simple plug and play.Start up: Again, this process was easy, you will need to go online or call for an activation code when prompted by the user interface on the generator. This will also allow you to register your generator. After going through the start up process, which in itself was easy, I did run into one snag that I expected prior to installation. When I tested the generator to start up and power my home, my central AC unit was set to call for air so when the switch transferred over to emergency power, there was too much of a load and the generator want into fault mode as it is designed to do. Again, I will say read your instructions as this is explained in them, there is a set of contacts inside the switch housing that are for the AC, you need to intercept the thermostat wire and run it through the AC contacts. Upon start up, if the switch measures to much of a start up load, it will open up those contacts allowing the generator to start up, balance out the load and then will close allowing the AC to start up normally.Overall, I am extremely pleased with this unit. For the first time in 12 years since I built my home, I am actually looking forward to a power outage! September 2, 2015
  • 2015-10-03T19:58:37.323-05:00
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There is a 3/4" NPT on inlet. Adapter supplied.

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  • 2015-10-03T19:55:56.168-05:00
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