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20kW1 Fortress Standby Generator

20kW1 Fortress Standby Generator

A perfect fit for any home, the 20kW1 Fortress standby generator powers all of a home's electrical needs easily and automatically. Keep your family safe, comfortable and free from the stress that comes with power outages.

20

kW

993cc

Displacement

3600

RPM

6 Year

Limited Warranty

Features

InfoHub™ Wireless Monitoring

Lets you monitor your generator's status on your computer, tablet or smartphone sending maintenance reminders so your generator is always ready for the next power outage. Sold separately. Click here for more information.

Symphony® II Power Management

Manages the distribution of power to your selected appliances automatically. Load management ensures the generator won't overload and shutdown so your family can continue with its daily routine. Transfer switch and modules sold separately.

Commercial Vanguard™ Engine

Our in-house state of the art equipment to enhance part control which makes the Vanguard™ Engine one of the best in the industry. For the dirty demanding environments, this engine is built to last.

Best in Class Warranty

Covers parts, labor and travel for the full-length of the warranty.2

Assembled and Engineered in the USA

With domestic and foreign parts.

Corrosion Resistant Durable Enclosure

Made from automotive-grade galvanneal steel to resist rust. Its advanced powder coat paint process results in years of protections against chips and abrasions.

Flexible Placement Options

With the ability to install your generator as close as 18 inches from your home.3

Low Idle Mode

Scheduled weekly test mode that runs at a low RPM for fewer disturbances and less fuel consumption. (Only on model #s 040587, 040589, 040609)

Superior Customer Support

Our product is backed by our nationwide dealer network and call center experts. Complete our web form below or visit the customer support portal to get your questions answered.

Financing Solution

We have partnered with Synchrony Bank to provide financing solutions that fit your needs. Special financing4 is available on qualified Briggs & Stratton Standby Generators only with the Standby Power Credit Card. 

1 This generator is rated in accordance with UL (Underwriters Laboratories) 2200 (stationary engine generator assemblies) and CSA (Canadian Standards Association) standard C22.2 No.100-14 (motors and generators).

2 See operator's manual or BRIGGSandSTRATTON.com for complete warranty details.

3 Installations must strictly comply with all applicable codes, industry standards, laws, regulations and provided installation manual. Running engines give off carbon monoxide, an ordorless, colorless, poisonous gas, so it is important to keep exhaust gas away from any windows, doors, ventilation intakes or crawl spaces. The installation manual contains specific instructions related to generator placement in addition to NFPA 37, including the requirement that carbon monoxide detectors be installed and maintained in your home or business.

Specs

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Model
040547
Running kW (LP)*
20
Running kW (NG)*
18
Running Amps (LP)*
83.3
Running Amps (NG)*
75.0
Engine Brand
Briggs & Stratton
Engine Displacement (cc)
993
Voltage (V)
120/240V AC, Single Phase, 1.0 pf
NG Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 187 ft3/hr
LP Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 2.31 gal/hr
Length (in)
48
Width (in)
34
Height (in)
31
Weight (lbs)
500
Warranty (Product)***
6 Year Parts, Labor & Travel Limited Warranty
Weekly Exerciser
Yes
Battery Charger
Yes
Model
040573
Running kW (LP)*
20,000
Running kW (NG)*
18,000
Running Amps (LP)*
83.3
Running Amps (NG)*
75
Engine Brand
Briggs & Stratton
Phase
1-Phase
Engine Displacement (cc)
993
Voltage (V)
120/240 V, Single Phase
NG Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 2.31 gal/hr
LP Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 187F3/hr
Length (in)
49.2
Width (in)
31.7
Height (in)
30.6
Weight (lbs)
443
Warranty (Product)***
6 Years
Weekly Exerciser
Yes
Battery Charger
Yes
Model
040587
Running kW (LP)*
20
Running kW (NG)*
18
Running Amps (LP)*
83.3
Running Amps (NG)*
75.5
Engine Brand
Vanguard®
Phase
1-Phase
Circuit Breaker Amps
100
Frequency (Hz)
60
Engine Displacement (cc)
993
Voltage (V)
120/240
Enclosure Materials
Steel
Sound Level (dBA) at 7 Meters
Low Idle Mode - 64 No Load - 67
NG Fuel Consumption at 50% Load** (BTU/hr)
150,000
LP Fuel Consumption at 50% Load** (BTU/hr)
152,000
Length (in)
50.5
Width (in)
32.9
Height (in)
31
Weight (lbs)
486
Warranty (Product)***
6 Year
Weekly Exerciser
6 Exercise Length Option
Battery Charger
Included
Model
040589
Running kW (LP)*
20
Running kW (NG)*
18
Running Amps (LP)*
75.5
Running Amps (NG)*
83.3
Engine Brand
Vanguard®
Phase
1-Phase
Circuit Breaker Amps
100
Frequency (Hz)
60
Engine Displacement (cc)
993
Voltage (V)
120/240
Enclosure Materials
Aluminum
Sound Level (dBA) at 7 Meters
Low Idle Mode - 64 No Load - 67
NG Fuel Consumption at 50% Load** (BTU/hr)
150,000
LP Fuel Consumption at 50% Load** (BTU/hr)
152,000
Length (in)
50.5
Width (in)
32.9
Height (in)
31
Weight (lbs)
440
Warranty (Product)***
6 Year
Weekly Exerciser
6 Exercise Length Options
Battery Charger
Included
Model
040592
Running kW (LP)*
20,000
Running kW (NG)*
18,000
Running Amps (LP)*
83.3
Running Amps (NG)*
75.0
Engine Brand
Briggs & Stratton
Phase
1-Phase
Engine Displacement (cc)
993
Voltage (V)
120/240V AC, Single Phase
NG Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 187 ft3/hr
LP Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 2.31 gal/hr
Length (in)
49.2
Width (in)
31.7
Height (in)
30.6
Weight (lbs)
443
Warranty (Product)***
10 Year Parts, Labor & Travel Limited Warranty
Weekly Exerciser
Yes
Battery Charger
Yes
Model
040609
Running kW (LP)*
20
Running kW (NG)*
18
Running Amps (LP)*
75.5
Running Amps (NG)*
83.3
Engine Brand
Vanguard®
Phase
1-Phase
Circuit Breaker Amps
100
Frequency (Hz)
60
Engine Displacement (cc)
993
Voltage (V)
120/240
Enclosure Materials
Aluminum
Sound Level (dBA) at 7 Meters
Low Idle Mode - 64 No Load - 67
NG Fuel Consumption at 50% Load** (BTU/hr)
150,000
LP Fuel Consumption at 50% Load** (BTU/hr)
152,000
Length (in)
50.5
Width (in)
32.9
Height (in)
31
Weight (lbs)
440
Warranty (Product)***
10 Year
Weekly Exerciser
6 Exercise Length Options
Battery Charger
Included
Model
040573
040547
040573
Running kW (LP)*
20,000
20
20,000
Running kW (NG)*
18,000
18
18,000
Running Amps (LP)*
83.3
83.3
83.3
Running Amps (NG)*
75
75.0
75
Engine Brand
Briggs & Stratton
Briggs & Stratton
Briggs & Stratton
Engine Displacement (cc)
993
993
993
Voltage (V)
120/240 V, Single Phase
120/240V AC, Single Phase, 1.0 pf
120/240 V, Single Phase
NG Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 2.31 gal/hr
50% Load = 187 ft3/hr
50% Load = 2.31 gal/hr
LP Fuel Consumption at 50% Load** (BTU/hr)
50% Load = 187F3/hr
50% Load = 2.31 gal/hr
50% Load = 187F3/hr
Length (in)
49.2
48
49.2
Width (in)
31.7
34
31.7
Height (in)
30.6
31
30.6
Weight (lbs)
443
500
443
Warranty (Product)***
6 Years
6 Year Parts, Labor & Travel Limited Warranty
6 Years
Weekly Exerciser
Yes
Yes
Yes
Battery Charger
Yes
Yes
Yes
Phase
1-Phase
1-Phase

*NG = Natural Gas; LP = Liquid Propane.
**Fuel consumption rates are estimated based on normal operating conditions. Generator operation may be greatly affected by elevation and the cycling operation of multiple electrical appliances - fuel flow rates may vary depending on these factors.
***See Operator's Manual or BRIGGSandSTRATTON.com for complete warranty details.

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