EG4 FlexBOSS21
EG4 FlexBOSS21
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EG4 FlexBOSS21 Hybrid Inverter | 48V Split Phase | 21kW PV Input
The EG4 FlexBOSS21 is a split phase, all-in-one, hybrid inverter designed for the residential and small commercial markets. With a 21kW usable PV (DC) input, the FlexBOSS21 provides high power output, generating 12kW of AC power during non-sunlight conditions and a full 16kW AC with solar PV gain. It is a powerful and versatile inverter which can feed-through 90 Amps of utility power from the grid at 120/240 VAC.
The FlexBOSS21 is an enhanced cousin to EG4’s flagship 18kPV inverter that has been designed to optimally work with EG4’s GridBOSS MID (power gateway). The combination of FlexBOSS21 and GridBOSS significantly reduces installation expenses by replacing unnecessary components and reducing installation time. This makes the FlexBOSS21-GridBOSS combination an unbeatable choice for customers looking to build powerful, cost-effective and scalable solar systems.
Versatile and Powerful Hybrid Inverter
The EG4 FlexBOSS21 is a versatile 48V split-phase, hybrid inverter/charger that offers the same dependable power as the 18kPV with enhanced flexibility. Powerful enough to start a 5-ton AC unit, the FlexBOSS21 supports 21kW of PV input. Capable of paralleling up to 10 units together, the FlexBOSS21 has an impressive total output of 160kW continuous when using pv input. Three MPPTs give users optimal control over their solar needs, while the updated EG4 monitoring software allows for convenient total remote management, complete with mobile notifications and remote setting. Seamless interaction with GridBOSS gives users control over their entire Energy Storage System (ESS).
Key Features:
- Flexible Power Options: Operate off-grid, with grid support, or sell excess power back to the grid.
- High PV Input Voltage: Supports up to 600V DC, allowing reduced cable sizes.
- Smart Connectivity: Remote access with Wi-Fi and closed-loop communication with compatible batteries.
- Safety-First Design: Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications.
Specifications:
- Input Voltage Range: 120/240VAC; 120/208VAC (Split-phase)
- Output Power: 16kW continuous when using pv input, with a peak surge capacity of 24kW
- Dimensions: 29.5 x 20.5 x 11.2 inches
- Weight: 88 lbs
- Warranty: 10-year standard warranty, covering all major components
Why Choose EG4 FlexBOSS21? The FlexBOSS21 combines efficiency, durability, and innovation, making it a top choice for those seeking robust energy solutions. Its advanced monitoring and safety features provide reliable power and peace of mind for residential or commercial installations.
Elevate Your Energy Solutions Today: Explore the potential of the EG4 FlexBOSS21 Hybrid Inverter and enhance your energy management system.
Important Breaker Information for Pairing with the EG4 GridBoss
Each EG4 GridBoss unit includes:
-
70A Breaker:
Compatible only with the EG4 18kPV Hybrid Inverter. -
Smart Port Breakers:
Rated at 30A, 40A, 60A, and 80A.
Please Note:
- You must purchase a 90A Breaker for use with the EG4 FlexBoss21 Hybrid Inverter.
- You must purchase a 50A Breaker separately for use with the EG4 12kPV Hybrid Inverter.
- A 125A Breaker (sold separately) can be used with either the Smart Port or Gen Port.
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I almost NEVER leave a 5 star review. They are reserved in my world for places that do something EXCEPTIONAL. Kyle A. And the crew at Cabin Depot are a group of those exceptional people. They patiently worked with us as we developed our off grid setup and provided not only fair prices, but wonderful follow-up with my installation and operational questions as our system came together. Thank you and we look forward to a continued relationship.
I purchased a drolet myriad III wood stove from cabin depot. Customer service was great, delivery was fast and they replied to all of my questions very quickly. When I received the wood stove I unboxed it while the driver was here (as suggested by the company). Everything was perfect and the driver from midland transportation was very accommodating.
A+ thank you very much!
I’ve taught customer service to many organizations in my professional career. I’m now long retired and still find excellent customer service difficult to come by!
The Cabin Depot, and especially Kyle Aubin, are exceptional examples of customer support and service!! My only regret was not reaching out sooner!
I would have saved myself significant time, lessened aggravation, and a happier installation of my EG46000XP and generator backup.
Lyle’s patience and response time, his pleasantness and professionalism, will contribute significantly to me looking first to them for future sales and service!
Recently added a EG4 LL battery to my existing system.
Cabin Depot was great to deal with, shipping was around a week., which is pretty good considering it was shipped across Canada.
Only delayed by 1 day but that was a UPS thing.
This battery was added to 3 existing EG4 Lifepower batteries.
Everything worked no issues at all., only thing was the communication ports are in different locations and the supplied cables are too short to reach,
No big deal.
All in all very happy and would order again
Propane stove came on time in perfect condition, super easy install, helpful customer service, very competitive price!! Just a good company. We will be buying more off grid supplies from this fantastic group of professionals!!
I was so impressed last year when I called from Alberta - searching for the right equipment (hot water on demand and propane heater… and I have to say I am impressed again - today was just a special order thermocouple to have as a spare - the service you provided for a 35 dollar part was above and beyond.

