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Generac Guardian 6721 16kW Generator

DISCONTINUED - AP Recommends Replacing with Generac 7035 16kW
5 Stars 9 product reviews
Average Product Review Rating: 5/5
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• Starts automatically for 24/7 continuous backup power protection
• Continuous Fuel Source from your home - LP or Natural Gas
• Digital controller with LED status and fault indicators
• Generac OHVI Engine
• All-weather aluminum enclosure

The Generac 6721 16kW Guardian Generator provides essential circuit power protection for your home, ensuring the necessities remain powered during an outage or up to whole house coverage when paired with load- shedding switches. Capable of backing up a five ton air conditioner. GENERAC OHVI® ENGINE Your Guardian Series generator might have to get you through days or weeks without utility power. The OHVI® engine, specifically designed for generator use, provides the reliability to power through the most severe outages. EVOLUTION® CONTROLLER The next generation of intuitive controllers featuring a multilingual, two-line LCD text display with color-coded, back lit buttons. CERTIFIED FOR 18" INSTALLATION TO THE HOME 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. EASY INSTALLATION When combined with a pre-wired transfer switch or Smart Switch, re-engineered connection points, and composite mounting pad that eliminates the need for a poured concrete base (unless specified by local codes), the Guardian Series 16 kW generator is easy to install. RATED FOR OPERATION IN AREAS WITH LOW NATURAL GAS PRESSURE In areas with low natural gas pressure, the Guardian Series 16 kW generator can operate on natural gas pressures of only 3.5 of water column. ALL-WEATHER ALUMINUM ENCLOSURE 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 and recommended for salt-air locations. TOOL-LESS FUEL CONVERSION Switch between natural gas and LP fuel in the field in a few seconds, without the need for any tools. TRUE POWER® TECHNOLOGY Best-in-class power quality with less than 5% total harmonic distortion means clean, smooth operation of your sensitive electronics and appliances. QUIET-TEST® MODE Thanks to Quiet-Test, your Guardian Series home standby generator runs its weekly self-test at a lower RPM for only five minutes. It's quieter than other brands, and consumes less fuel. Choose your schedule - weekly, bi-weekly or monthly. MOBILE LINK® COMPATIBLE Take advantage of Generac's Mobile Link cellular remote monitoring system and check on your generator's status using your computer, tablet or smartphone, even when you are away. Sold separately. 24/7/365 CUSTOMER SUPPORT Power outages don't always occur during normal working hours. That's why Generac's customer care call center, right here in Wisconsin, provides support any time of day or night, all year long. Generac is standing by 24/7, every minute of every day, to answer your questions. 5-YEAR LIMITED WARRANTY


6721 Specifications Sheet
6721 Owner's Manual
6721 Installation Guide
6721 Warranty

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Product Reviews

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  1. Pleased with Purchase

    4 star rating Product Review Rating: 4/5

    Posted by on Dec 17, 2015

    I really did not want to spend the money on home standby generator but was just sick of being without power a couple of times a year. last time there was power outage the basement flooded because the sump lost power even though I had back-up battery system for the sump pump. Never again. I ordered the my Generac 16kW generator on Monday and it arrived on Wednesday. Unbelievably quick delivery for something this big. No regrets on the purchase. I did not have an electrician and asked AP Electric for a recommendation on installers. They gave me 2 recommendations. I received bids from both and there was a $585 difference between the 2 bids. Selected low bid and I could not be happier with the install and the installation recommendation I received from AP Electric.

  2. Generator works like a dream

    5 star rating Product Review Rating: 5/5

    Posted by on Dec 09, 2015

    This generator is working like a dream. It has been installed for a couple of months now and works great. We did have a few questions about this generator and the customer support from AP Electric was excellent.

  3. Its a workhorse

    5 star rating Product Review Rating: 5/5

    Posted by on May 14, 2015

    This generator works great. When we had our first power outage, it started right up and powered the house. It starts every week to test itself which is a great reassurance that it will work when we need it. We don't even notice it anymore. We just love it.

  4. Automatic Insurance

    4 star rating Product Review Rating: 4/5

    Posted by on May 14, 2015

    This generator is completely automatic. It has done a great job supplying our electrical needs during power outages.

  5. I sleep soundly now

    5 star rating Product Review Rating: 5/5

    Posted by on May 12, 2015

    We live in a flood prone area. With the Generac home standby generator, I never have to worry about my basement flooding due to the sump pump not working. When we are not home, we get messages on the phone that the generator did its weekly test, or even if it had to fire up. The cost of the generator and install is nothing compared to the potential loss from a flooded basement.

  6. Safe and Secure power.

    5 star rating Product Review Rating: 5/5

    Posted by on May 06, 2015

    Has always started when needed, once during a tornado! Our utility company has a terrible service record, We should all realize one thing, YOU ARE ON YOUR OWN. This spring, after a storm, we were down for 36 hours straight. The neighbors hated us as they watched their freezers melt down. This Generac generator has been a great investment in safety and security

  7. Aluminum is better

    4 star rating Product Review Rating: 4/5

    Posted by on Apr 27, 2015

    My wife and I purchased a Generac 14kwv before they were discontinued. We didn't know that it would rust really fast because we're near salt water and the enclosure was steel. The generator was sold and when I called AP i was told that I could avoid that with aluminum. I don't know why Generac doesn't just make them all in aluminum! Regardless we bought Generac model 6721and just hope this one will last me longer. It shipped out today and shouldn't take too long to arrive.

  8. AP Helped me select BEST Generator for Me

    5 star rating Product Review Rating: 5/5

    Posted by on Apr 27, 2015

    I needed a generator for my smaller home. I was looking at the larger 22000 watt units, and that is what I called in to ask about. The rep on the phone asked me some questions, and after checking with my electrician, we decided that was too big. The 16kw Generac was the perfect generator. We paid extra for the aluminum housing. We had to order the switch separate, because my house has 100amp service. But, all is good, the generator arrived in short order after I placed the order, and after the gas and electric were installed, we are ready to go. Great Service and excellent pricing by AP

  9. Excellent Price

    5 star rating Product Review Rating: 5/5

    Posted by on Feb 19, 2015

    Submitted on August 29, 2014
    Very Fast, friendly and professional.

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