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Please see replacement Item# 54317. Generac Guardian Air-Cooled Standby Generator — 22kW (LP)/19.5kW (NG), 200 Amp Service-Rated Automatic Transfer Switch, Model# 6551

Item# 45335
Please see replacement Item# 54317. Generac Guardian Air-Cooled Standby Generator — 22kW (LP)/19.5kW (NG), 200 Amp Service-Rated Automatic Transfer Switch, Model# 6551

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Please see replacement Item# 54317. Generac Guardian Air-Cooled Standby Generator — 22kW (LP)/19.5kW (NG), 200 Amp Service-Rated Automatic Transfer Switch, Model# 6551

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  • Includes 200-Amp service-rated automatic transfer switch
  • Generac OHVI® engine is designed to run for extended periods, ensuring reliable, uninterrupted power
  • Generac's Evolution Controller features a dual-line, improved multilingual LCD display for easy monitoring and management of generator functions, built-in hour meter and external at-a-glance indicator lights
  • Install as close as 18in. to home as certified by NFPA standards or directed by local codes
  • True Power™ technology provides clean, smooth operation of sensitive electronics and appliances

See full description

  • Description

  • Key Specs

  • Reviews

  • Q & A

  • Accessories

  • Warranty

  • Compare

Product Summary

This Generac Guardian Series Standby Generator protects your home automatically 24/7. Runs on natural gas or liquid propane (LP) fuel, and sits outside just like a central air conditioning unit. No refueling, no manual starting and no extension cords. Delivers power directly to your home’s electrical system, backing up your entire home or just the most essential items. Add even greater convenience with a Mobile Link (not included), Generac’s cellular remote monitoring system. Tool-less fuel conversion, external main circuit breaker, system status LED, and external GFCI outlet. Mobile Link and remote monitoring systems available, sold separately. Not intended for use as primary power in place of utility or in life-support applications. Read the owner's manual in its entirety before using this product.

What's Included

  • (1) 22kW generator, Model# 6551
  • (1) 200 Amp service-rated automatic transfer switch
  • (1) Pre-attached composite mounting pad

Downloads

Product Manual
Additional Product Info

Features + Benefits

  • Includes 200-Amp service-rated automatic transfer switch
  • Generac OHVI® engine is designed to run for extended periods, ensuring reliable, uninterrupted power
  • Generac's Evolution Controller features a dual-line, improved multilingual LCD display for easy monitoring and management of generator functions, built-in hour meter and external at-a-glance indicator lights
  • Install as close as 18in. to home as certified by NFPA standards or directed by local codes
  • True Power™ technology provides clean, smooth operation of sensitive electronics and appliances
  • Quiet-Test™ weekly self-test mode runs at lower RPM, is quieter and consumes less fuel
  • Sturdy, corrosion-resistant aluminum enclosure
  • Tool-less fuel conversion with swivel-action fuel selector dial allows for easy switching between natural gas and LP fuels
  • Mobile Link™ compatibility for adding Mobile Link wireless remote monitoring system to receive status updates using your computer, tablet or smart phone
  • Battery required, not included
  • 24/7 Generac customer care support 365 days a year
  • Engineered and built in U.S.A.
  • 5-year limited warranty

Key Specs

AttributeSpecification

item#

45335

Brand

Generac

Manufacturer's Warranty

5 year limited warranty

Ship Weight

556.0 LB

Voltage

120/240

Rated Kilowatts LP

22

Rated Kilowatts NG

19.5

Max. Amps

91.7

Fuel Type

Multi-Fuel

Engine Brand

Generac
AttributeSpecification

Engine Model

OHVI V-Twin

Engine Displacement

999 cc

Noise Level

66 dB

Enclosure Material

Aluminum

Battery Required

Yes

Battery Included

No

Transfer Switch Amps

200

Auto Shutdown

Yes

Engine Cooling

Air

Dimensions L x W x H (in.)

48 x 25 x 29

Reviews

Questions & Answers

29 Reviews This action will navigate to reviews.

Questions

1–10 of 15 Questions  
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  1. what size propane tank is required

    1. The manual says that at least a 250 gallon propane tank is required.

      Helpful?

    2. The size of propane tank utilized in a configuration featuring Generac’s Guardian Series automatic standby generators should be no smaller than 250 gallons.

      Helpful?

    3. This Generac Guardian Air-Cooled Standby Generator has a required fuel pressure for liquid
      propane vapor of 10-12 in water column (19-22 mm mercury). You would want to go with at least a 300 gallon tank. The primary regulator for the propane supply is not included with the generator. Please see the owner's manual for more details.

      Helpful?

  2. Which side does exhaust blow out when facing front asin picture?

    1. Exhaust comes out the left side when facing the generator. I turned mine away from the house to limit the noise of the engine in the home.

      Helpful?

    2. Left side when facing the front of the unit.

      Helpful?

    3. When facing the front of the unit the exhaust will blow out the left side of the generator’s enclosure.

      Helpful?

  3. how long can this generator run with unlimited supply of propane? can it function for a week without additional maintanence? thanks

    1. Oil change is recommended seasonally under ordinary duty but a change every 200 hours is expected. My neighbor has one than ran 10 days straight in 2012 after the straight line 80 mph winds took out the power here. These machines are built for long service but a shutdown and oil change should be done according to manufacturers recommendations.

      Helpful?

    2. Generac's automatic standby generators should not run continuously for any longer than 24 hours. After 24 hours of operation, the unit will need to be shut down so that maintenance-related tasks can be performed.

      Helpful?

  4. battery for generator

    i just got model #6551 gen. what kind of battery does it need and what is your part # for it?

    1. After speaking with a Representative from Northern, I went to my local auto supply store and purchased a Group 26R 12 Volt 540CCA battery.

      Helpful?

    2. This Generac Guardian Air-Cooled Standby Generator requires a Group 26R 12 volt battery with a minimum of 525 CCA (cold cranking amps.) We do not have a battery at this time that meets the CCA.

      Helpful?

  5. Are there padeyes on the top for lifting or must it be forklifted from bottom?

    1. Must be forklifted

      Helpful?

    2. The generator has to be fork lifted from the bottom.

      Helpful?

  6. NG filtration/water trap for this NG generator application

    Can you recommend a Natural Gas filtering system (with integral water trap) for this generator's NG supply line, that will allow the NG flowrates needed when the gen set is at "full load."

    1 answer

    1. The Generac Guardian Generator when hooked up to a utility supplied Natural Gas supply line would not require a filtering system. Generac does not recommend use of a Natural Gas well supply line.

      Helpful?

  7. What happens after 24 hours

    It states that the generator should not run continuously over 24 hrs. In certain circumstances, the power has been lost for over 4 days. How do you operate the generator in this situation.

    1 answer

    1. Generac recommends the generator be shut down every 24 hours for a routine maintenance check. Once the maintenance check and any necessary services or repairs are done, the generator can be returned to use.

      Helpful?

  8. will the 200 amp automatic transfer switch have a breaker installed in it.

    1 answer

    1. The 200 AMP service rated transfer switch included with Generac's 22kw automatic standby generator, model number 6551, is not a circuited switch, it does not feature circuit breakers.

      Helpful?

  9. is mounting pad included?

    1 answer

    1. The mounting pad is included with this generator.

      Helpful?

  10. What type oil is suppied when the unit is shipped?

    1 answer

    1. This generator will ship out with SAE 30 oil.

      Helpful?

Warranty

Manufacturer's Warranty

5 year limited warranty