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Generac Synergy 6055 20kW Generator with 200A SE Transfer Switch

DISCONTINUED - AP Recommends Replacing with Generac 7040 20kW
5 Stars 10 product reviews
Average Product Review Rating: 5/5
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PATENTED G-FLEX™ TECHNOLOGY Allows the Generac Synergy home standby generator to vary its speed based upon electrical demand. It will run slower, and quieter, when you use less electricity. And during its weekly exercise, you’ll hear only about as much sound as if you were riding in a luxury car. The Synergy also consumes less fuel when electricity demand is light, saving you money. And G-Flex technology delivers electricity with less than 2.0% total harmonic distortion (THD), lower than IEEE standards for utility power, to properly power modern electronics and sensitive appliances.

Your Generac Synergy generator might have to get you through days, or weeks, without utility power. Generac’s OHVI® Engine is specifically designed for generator use, provides the reliability to power through the most severe outages.

The next generation of intuitive controllers featuring a multilingual, two-line LCD text display with color-coded, back lit buttons.

Check on your generator’s status even when you are away with Mobile Link cellular remote monitoring. Use your computer, tablet, or smartphone. Downloadable app available for iOS® and Android™. Comes standard with Generac Synergy.

Third-party certified to NFPA standards to be installed as close as 18” from the home’s exterior wall, provided it is located away from doors, windows, and fresh-air intakes, and unless otherwise directed by local codes.

Our durable powder-coat finish helps make the sturdy aluminum enclosure perfect for all weather conditions. It’s also able to withstand 150 mph winds.

The Generac Synergy runs on natural gas and LP fuel, and easily converts during installation without the need for tools.

G-Flex™ technology allows the Generac Synergy to run at a very low speed during its periodic exercise. You’ll hear about as much sound as you would riding in a luxury car. Select weekly, bi-weekly or monthly for just 5 minutes.



6055 Specifications Sheet
6055 Owner's Manual
6055 Warranty

Product Videos

Generac Synergy 6055 Home Standby Generator Introduction 02:33
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Product Reviews

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  1. Awesome

    5 star rating Product Review Rating: 5/5

    Posted by on Apr 07, 2016

    We ordered the Synergy 20kw with natural gas and LOVE it! Had to use it twice already! It started up and ran like a dream for 6 hrs and then 1 hr. It has the mobile link and we get status updates daily. So happy it came with the link and aluminum case since we live about 15 miles from the ocean. This product was worth every penny. We would highly recommend it.

  2. Significant Upgrade

    5 star rating Product Review Rating: 5/5

    Posted by on Dec 04, 2015

    Replaced a 2005 Generac Centurion 15kw, Enclosure base rusted to pieces. Aluminum housing eliminates that and much less noise. Advanced technology for lower rpm / load applied, along with Load Management in SE Transfer Switch is impressive.

  3. Very Pleased

    5 star rating Product Review Rating: 5/5

    Posted by on Dec 03, 2015

    Great 22kW generator. Purchased the Generac 6055 because of the aluminum enclosure so I never have to worry about rust. It has been installed for about 3 months now and performs perfectly. Fast shipping from AP Electric.

  4. Perfect

    5 star rating Product Review Rating: 5/5

    Posted by on Oct 14, 2015

    The Generac 6055 20kw generator is a fantastic generator. Not only did I buy one but my father bought one as well. We are both very pleased with our purchase. Great service by AP Electric I might add as well.

  5. On the way

    5 star rating Product Review Rating: 5/5

    Posted by on Aug 04, 2015

    It's about time they brought the aluminum enclosure back. About a year ago I was interested in getting the 5875 Generac generator and then it was gone. Next thing I know the 20kw is only offered in steel and I sat there going why the hell would they do that? I assumed it was to save money. Glad to have it back now. The 6055 Generac synergy generator appears to be just as good as the generator it replaced. Still air-cooled so that's a plus with idle. Happy that I waited all this time to finally get my backup generator. Not much happening in Iowa right now, but that could change any moment. Waiting patiently for this 20kw generator to arrive at my home.

  6. About the same

    4 star rating Product Review Rating: 4/5

    Posted by on Aug 03, 2015

    I'm not seeing a big difference between this 20kw Generac Synergy series generator and the 20kw Generac Guardian series generator other than the aluminum enclosure and the price. Is that the only difference between the two? I'm going to assume that there is and that's why I've decided to purchase it. I'd rather have a current model generator like the 6055 then purchase the previous model and risk not having support for it. Looking forward to having the protection of an automatic generator at my residence.

  7. Brand New

    5 star rating Product Review Rating: 5/5

    Posted by on Jul 16, 2015

    You proved me wrong AP Electric. The internet is filled with scammers/con artists so I was 100% sure that the Generac 6055 synergy generator that we were going to receive was a refurbished generator. With no tax and free shipping I just couldn't see it shipping all the way to Wyoming and being brand new. You must get good deals on the 20kw air-cooled generators, but either way I'm content. All the reviews I'm seeing say it's a great machine and I have faith in Generac. Wish it was steel so I could have saved a little money since it's only an emergency back up generator and won't be used every single day. If I have any other comments I'll update this when the generator is received.

  8. 6055 synergy

    5 star rating Product Review Rating: 5/5

    Posted by on Jul 16, 2015

    I bought this just a moment ago so this is more of a preview. Don't really see a lot of differences between this 6055 20kw Generac generator and the 6729 20kw Generac generator. The aluminum enclosure seems to be about it. I don't mind paying the extra since rusting won't be an issue. Thanks for the great service AP.

  9. Honest company

    5 star rating Product Review Rating: 5/5

    Posted by on Jul 13, 2015

    My original plan was to buy the Generac model 6729 20kw generator. I live in Florida and want to get an air-cooled home standby generator as a backup before a storm hits my area. I spoke with Dom and he recommended aluminum vs the steel cabinet on the generator I was looking at. He suggested this Generac 6055 20kw generator to be a better fit. I researched some to find out that steel would have been horrible since I'm right on the coast. The salt water would have destroyed the steel in no time. I'm so appreciative because your company could have just sold me any 20kw generator, but you took the time to make sure it was exactly what I needed.

  10. Generac Synergy 6055

    5 star rating Product Review Rating: 5/5

    Posted by on Jul 11, 2015

    You guys (or girls) put this up just in time. I kept hearing about the Generac new 20kw synergy generator and you didn't have it up. I looked several times and some of your competitors did, but not you. I don't know why I looked one last time I just wanted to check. You finally offer it! I've ordered parts from you in the past on my older 20kw generator and wanted to keep all my needs with AP. My previous 20kw generator was a champ and then I moved so I'm getting another one. Looks like this air-cooled generator will hold up just fine. I had considered a portable until I found out there can't be made automatic. I'd prefer to go with a home standby Generac generator like this 20kw.

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