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EG4 FlexBOSS21 Hybrid Inverter

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input
$3,599.99 - $3,599.99
$3,599.99
$3,599.99 - $3,599.99
$3,599.99
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EG4 FlexBoss21 Manual & Spec Sheet

View Manual HERE
View Spec Sheet HERE

EG4

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input

The EG4 FlexBOSS21 is a split-phase, all-in-one hybrid inverter designed for residential and small commercial applications. With a 21kW usable PV (DC) input, it delivers high power output, providing 12kW of AC power during non-sunlight hours and a full 16kW AC with solar PV input. This powerful and versatile inverter can pass through up to 90 amps of utility power from the grid at 120/240 VAC.

An enhanced version of EG4's flagship 18kPV inverter, the FlexBOSS21 is optimized to work seamlessly with EG4's GridBOSS MID (power gateway). Together, the FlexBOSS21 and GridBOSS reduce installation costs by eliminating unnecessary components and cutting installation time. This combination offers an unmatched solution for customers seeking efficient, cost-effective, and scalable solar power systems.

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input
Lowest Price Guarantee
Authorized EG4 Dealer
Genuine EG4 Equipment
10-Year Warranty Coverage
Free Shipping
0% APR Financing via Affirm

Why the EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input

PV Input

21kW max usable, 24kW max input. V3.1

Continuous AC Output

16kW @ 240V, 13.8kW @ 208V

Nominal Output Voltage

120/240V | 120/208V | 240V

Includes

1 x 90A Breaker (Compatible only with the EG4 FlexBOSS21) & Smart Port Breakers Rated at 30A, 40A, 60A, and 80A.

Operate off-grid, with grid support, or sell excess power

Operate off-grid, with grid support, or sell excess power back to the grid.

Supports up to 600V DC, allowing reduced cable

Supports up to 600V DC, allowing reduced cable sizes.

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input Specifications

PV Input 21kW max usable, 24kW max input. V3.1
Continuous AC Output 16kW @ 240V, 13.8kW @ 208V
Nominal Current 50A
Nominal Output Voltage 120/240V | 120/208V | 240V
Continuous Output Power 12000VA
Dimensions 30.4×22.3×11.2 in.
Weight 88 lbs
Your Satisfaction with EG4 is Guaranteed 10-Year Limited Warranty

Documentation & Downloads

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input Spec Sheet (PDF)

Lowest Price Guarantee

Find it cheaper at another authorized EG4 dealer? Call us before you order and we will take care of you.

Authorized EG4 Dealer

This is genuine EG4 equipment, sold and supported by Renewable Outdoors as an authorized dealer. Coverage: 10-Year per the manufacturer terms stated for this product.

Help From People Who Sell These Every Day

Call (303) 876-7654. We would rather spend ten minutes sizing your system correctly than process a return later.

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input: Frequently Asked Questions

What's covered under the warranty?
EG4 backs the FlexBOSS21 16kw AC Hybrid Inverter with a 10-Year warranty per the manufacturer's terms stated for this product. As your retailer, Renewable Outdoors can also help you navigate a warranty claim — call us at (303) 876-7654.
What is the power output of the FlexBOSS21 16kw AC Hybrid Inverter?
The FlexBOSS21 16kw AC Hybrid Inverter is rated at 12000VA (Continuous Output Power). Check the spec table above for the full electrical ratings before pairing it with other equipment.
What voltage does the FlexBOSS21 16kw AC Hybrid Inverter run on?
The FlexBOSS21 16kw AC Hybrid Inverter operates at 120/240V | 120/208V | 240V (Nominal Output Voltage). Make sure the rest of your system is built for the same voltage before ordering.
How big and heavy is the FlexBOSS21 16kw AC Hybrid Inverter?
The FlexBOSS21 16kw AC Hybrid Inverter has dimensions of 30.4×22.3×11.2 in. and a weight of 88 lbs. Plan your mounting and placement around those figures.
Is this genuine EG4 equipment?
Yes. Renewable Outdoors is an authorized EG4 dealer, and this product is genuine EG4 equipment.
Does Renewable Outdoors offer financing or price matching?
Yes. We offer 0% APR financing options through Affirm at checkout, and the FlexBOSS21 16kw AC Hybrid Inverter is backed by our Lowest Price Guarantee — if you find it cheaper at another authorized EG4 dealer, call us at (303) 876-7654 before you order and we will take care of you.

Customer Reviews

Overall rating: 5.0 / 5 from 3 reviews.

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