SKU: 19188759521

Briggs & Stratton Fortress 48kW Liquid Cooled Standby Generator Single Phase

Sale price$10456.20 Regular price$11618.00
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Description

Briggs & Stratton Fortress 48kW Liquid Cooled Standby Generator Single PhaseBriggs and Stratton 48 kW Fortress Standby Generator Liquid cooled, emergency grade backup power that starts automatically in seconds (Auto Transfer Switch required) If you are backing up a large home, a multi building property, or a light commercial site, you need more than a typical air cooled standby generator. The Briggs and Stratton 48 kW Fortress is a liquid cooled, emergency grade standby generator built to deliver serious power with stable

Briggs and Stratton 48 kW Fortress Standby Generator

Liquid-cooled, emergency-grade backup power that starts automatically in seconds (Auto Transfer Switch required)

If you are backing up a large home, a multi-building property, or a light commercial site, you need more than a typical air-cooled standby generator. The Briggs and Stratton 48 kW Fortress is a liquid-cooled, emergency-grade standby generator built to deliver serious power with stable voltage for modern electronics, quieter 1800 RPM operation, and a warranty that takes a lot of stress out of ownership.

This is the kind of system you install once and count on when storms, outages, and grid issues show up at the worst time.


What the Fortress 48 kW does when the power goes out

With an installed automatic transfer switch (ATS), the Fortress system:

  • Detects utility power loss
  • Starts automatically within seconds
  • Transfers your building to generator power
  • Monitors utility restoration
  • Transfers back to utility power when it is stable

No manual steps. No cords. No late-night scramble.

Important: This generator requires an automatic transfer switch. Transfer switch not included.


Big, steady power for real-world loads

48,000 watts of standby output

  • Rated output: 48,000W
  • Single-phase output: 120/240V
  • Rated amps: 200A
  • Frequency: 60 Hz

That level of output is designed for larger electrical demands where you want strong coverage across critical loads and comfort loads, not just a few circuits.


Liquid-cooled 4.3L 6-cylinder engine at 1800 RPM

At the heart of the Fortress is a 4.3L industrial 6-cylinder liquid-cooled engine running at 1800 RPM.

Why that matters:

  • Lower RPM operation supports better long-run durability than high-RPM standby units
  • Liquid cooling helps maintain stable operating temps during extended outages
  • Quieter operation for its class, especially compared to high-RPM designs

This is a serious engine platform built for standby reliability.


Runs on natural gas or propane

The Fortress 48 kW can be configured for natural gas (NG) or liquid propane (LP):

  • Connect to your home’s NG supply, or
  • Connect to a properly sized LP tank

Fuel planning is a major part of any large standby setup. Here are the published consumption numbers so you can plan line sizing and storage correctly.

Fuel consumption

Natural Gas

  • 50% load: 328 ft³/hr
  • 100% load: 511 ft³/hr

Propane (LP)

  • 50% load: 3.68 gal/hr
  • 100% load: 5.82 gal/hr

Clean power for sensitive electronics

Today’s homes and businesses have a lot of expensive boards and devices that do not like unstable power. The Fortress includes a computer-friendly brushless alternator with automatic voltage regulation, helping protect:

  • Network gear (modems, routers, access points)
  • Computers and office equipment
  • Security systems and cameras
  • Smart appliances and modern HVAC controls

Clean, regulated output matters just as much as total watts.


Smarter control with the Briggs and Stratton AMF Controller (UL Recognized)

The built-in AMF controller gives you visibility and control without making things complicated:

  • Easy-to-read alpha-numeric scrolling display
  • Monitors diagnostic conditions
  • Displays fault codes
  • Simple weekly exercise-cycle scheduling

You get the confidence of knowing the unit is ready and the clarity to troubleshoot quickly if an alert appears.


Built for weather, built for service

Corrosion-resistant aluminum enclosure

The enclosure is designed to hold up in harsh climates and protect the generator from extreme weather.

Convenient service access points

Routine maintenance should not require unnecessary disassembly. Service access points are designed to reduce service time and hassle.

Pre-installed block heater

Cold starts can be where standby systems struggle. A pre-installed block heater supports easier cold-weather starting and more consistent performance.

Turnkey extras included

This unit includes:

  • Automatic battery charger
  • Block heater
  • Hour meter

Less piecing together. More ready-to-run.


Sound level and physical specs

  • Noise level: 67 dB at 7m
  • Weight: 1,635 lbs
  • Dimensions: 91 in L x 39.4 in W x 41 in H
  • Enclosure: Aluminum
  • Cooling: Liquid-cooled
  • Circuit breaker size: 200A
  • UL listed: Yes
  • CARB compliant: Yes
  • Made in USA: Yes
  • Grade type: Emergency

Requirements (do not skip these)

To install and operate as designed:

  • Automatic transfer switch required (not included)
  • Requires 775 CCA starting battery (not included)
  • Concrete mounting pad required (not included)

This is a heavy, high-output standby generator. A professional installation is standard for safety, code compliance, and proper fuel delivery.


Warranty

  • Consumer warranty: 6 years
  • Commercial warranty: 2 years

The 6-year coverage includes parts, labor, and travel, which is a major advantage for a generator in this size class.


Best fit uses

The Fortress 48 kW is a strong fit for:

  • Large homes with significant electrical demand
  • Properties with multiple critical systems (security, networking, pumps, refrigeration)
  • Light commercial buildings that need reliable standby power
  • Farms and ranches that cannot afford downtime

Bottom line

The Briggs and Stratton 48 kW Fortress is a high-capacity, liquid-cooled standby generator built for automatic backup power, clean output for sensitive electronics, and long-term confidence backed by an industry-leading warranty. If you want a serious standby system that starts fast and runs steady, this is the right tier of equipment.

Resource

Manuals:

Generator Sizing Chart

Spec Sheet

Product Manual

Controller Manual

Warranty 

Energy Systems Central is an authorized dealer of BAS Energy Systems.

Warranty Document

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 19188759521

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C
Lake Worth, US
★★★★★ 5
My puppies favorite bone to chew
I’ve bought at least a half a dozen of puppy bones for my doggie to try, the majority being from Nylabone, and the others from hartz. Her first bone was a pink puppy Nylabone xsmall sise. She definitely must have liked that one but unfortunately I felt like I had to take it away from her too soon, she was teething more then, but even so, thought it was unsafe when I saw little pieces come off and her trying to chew them. I really like these the best, though I don’t think I’ll be ordering any more at least not until she finishes her new ones. I don’t know what flavor she likes more, it might even be a color thing, but I think she prefers the orange ones which are peanut butter flavored. These are really ideal for toy breeds. My pup is still growing, she’s almost 7 months now, but unsure when she will stop growing, for reference she is a chocolate sable yorkiepoo, not sure of how much she weighs right now, but would estimate she weighs around 5.5-6 pounds. These are perfect for her, and I feel like they out live the other ones I’ve gotten, or she just has more interest in them. I bought a second package on subscribe and save (or possibly on my first and forgot I had a new order and didn’t return), but didn’t open the new package until recently as I felt the first pack were starting to look a bit knawed off, but in the middle there was still plenty of chew left. Oddly, she has prefered the old orange one vs the brand new orange one despite them being the exact same toy and flavor. I think she just hasn’t broken it in yet and I overloaded her with too many toys! I also got them for a great price, for some reason I noticed that the price increased nearly double of what I paid, and now they habe decreased a bit but still are about $2 more than what I paid. She loves all toys, and has many plush kinds. She still teeths, so when she is extra hyper and such, I feel like the bone helps occupy her for a moment. All in all I’d reccomend these out of any puppy bones to chew for toy breeds!
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Reviewed in the United States on April 2, 2022
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J CASSIN
Battle Creek, US
★★★★★ 4
Nice chew toy
Puppy likes but for me to hold so she can chew is a little difficult.
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Reviewed in the United States on May 8, 2026
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Amazon Customer
Belleville, US
★★★★★ 5
Love nylabones
Nylabbones did it again. The pugs love these. They're so cute and tiny. Perfect for their lithe selves. They're still safe and soft and very chewable.
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Reviewed in the United States on November 16, 2025
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Anoni Miss
Belleville, US
★★★★★ 3
Not safe, easily chewed bits off
Mixed feelings. My puppies love them and love to chew on them but also chewed the edges off pretty quickly. I had to take away the first one after only a couple days of intermittent chew so it’s really not durable or long lasting. I don’t feel this is safe for a 12 week old puppy which is super small and can be a choking hazard.
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Reviewed in the United States on October 6, 2025
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Pooh
New York, US
★★★★★ 5
Very Small
These are tiny! Just perfect for my little dogs but one was lost within the first few minutes so I had to order another. I'm not so sure how safe it is for the fur children to chew on non-edible, non-digestible plastics but they seem to really like them.
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Reviewed in the United States on September 28, 2025

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