WEN GN400i Generator Review

In an era where everything is connected, power outages can present a considerable problem.

They can not only force you to endure the winter cold, make you unable to work, but can also risk your health, especially if you rely on a device such as CPAP. 

Thankfully, a portable generator like the  Wen GN400i  generator can keep you safe and connected when power problems come your way.


These fantastic pieces of equipment ensure that medical equipment and tools operate safely. At all times, your freezers and refrigerators remain functional, and that your cooling and heating systems remain working as well.

Generators also prove handy when camping, tailgating, or working at any remote place. Even a relatively small portable power generator can provide electrical energy for lights, your power tools, small appliances while camping outdoors.

You can also use a portable generator to power and run standard construction and building tools such as drills, saws, air compressors as well as paint sprayers. When preparing yourself for the inevitable power outage, you have every reason to have a portable generator at your disposal.

WEN GN400i 4000 Watt Inverter Generator

This reputable brand has been producing consistently reliable open frame generators for decades, and this could well be the reason why this particular device is a highly sought-after generator. Whether you are looking to power a large worksite, cabin, or your home during an emergency, the Wen GN400i power generator can handle it.


As skilled service technicians for portable generators, we will provide you with an extensive review of this incredible machine. At a glance, the Wen GN400i  boasts nearly everything any homeowner would want from a top-notch portable inverter generator.


This generator guarantees adequate power when you need it. It provides stable power that’s is free from drops and voltage spikes. This makes it safe to use with your mobile phones, laptops, and any other sensitive electronics of yours.

WEN GN400i Engines

Its astounding 212cc four-stroke OHV engines provide up to 4,000 surge watts and 3,500 rated watts power. The 1.85-gallon tank guarantees at least seven hours of efficient and uninterrupted hours of half-load runtime.


The generator’s control panel is equipped with two 5V USB ports, two three-prong 120V NEMA 5-20R receptacles as well as a single 120 RV-ready TT-30R receptacle. Its highly compact design and the included mobility kit ultimately make this powerhouse a fantastic generator to have on hand just in case you face an electricity crisis in the future.



The WEN 4000-watt open frame inverter generator offers clean energy, free from voltage spikes and drops for safe use with mobile phones, laptops, and other sensitive electronics.


This excellent 212cc four-stroke OHV engine produces up to 4000 surge watts and 3500 rated watts of energy. the generator is specifically designed to mirror a typical pure sine wave. It significantly reduces total distortion to below 0.3% at no load and under 1.2% at full load, making you safely operate sensitive electronics.


Its ultra-efficient 1.85-gallon fuel tank offers more than seven hours of uninterrupted power. In contrast, the fully-packed panel comes equipped with 2 3-prong 120V NEMA 5-20R receptacles, 2 5V USB ports, and one 120V RV-ready TT-30R receptacle. maximize fuel economy by the economy-mode switch.


The economy-mode switch allows the generator’s engine to automatically adjust its fuel usage as devices are plugged into and subsequently unplugged from the panel. This effectively makes the generator fuel-efficient by preventing unnecessary usage of gasoline.


Need more clean power? Seamlessly connect up two wen inverter generators using the device’s Wen parallel connection kit to have an increased wattage output amongst multiple units.


Low-fuel and low-oil automatic shutdown function holistically with the built-in overload protection and indicator lights to safeguard the generator and the connected electronics from damage. And because this generator is from the WEN, you can rest assured that a two-year warranty covers the device for added peace of mind.



  • It features an electric start.
  • Parallel-ready panel to allow connection of any compatible inverter generators for increased wattage.
  • Wheel kit included.
  • Inverter technology.
  • Quiet operation.
  • Relatively affordable.
  • The generator has a highly lightweight design.
  • It has sufficient power output for any home application.
  • Open frame inverter technology.
  • Seven hours of run time.


  • No weather protection

Features and Specifications of WEN GN400i

  • Product dimensions: 19.8 by 13.8 by 18.9 inches.
  • Product weight: 66.1 pounds.
  • Manufacturer: WEN.
  • Wattage: 4000 starting /3500 running watts.
  • Fuel type: Gasoline.
  • Fuel tank capacity: 1.85 gallons.
  • Outlets: 2 120-V AC, 1 30-amp RV outlet, 1 12-V DC, 2 USB ports.
  • Engine: 2122cc four-stroke OHV.
  • Starting method: Manual recoil/Electric.


Power and Runtime

As already mentioned, a 212cc OHV four-stroke engine powers this fantastic portable inverter generator. It delivers 120 V and operates on gasoline, providing a running wattage of 4000 watts. What’s more, thanks to the included parallel kit included, you can easily double the power output by connecting the generator to a similar compatible generator.


It is imperative to note that the 4000 watt open frame inverter generator features an eco-mode switch that enables the engine to operate at a relatively RMP when the electrical energy demand is less than 25% of the rated output.


Thus, despite being among the most affordable power generators, the Wen product boasts arguably the lowest THD, Total Harmonic Distortion specifications, at less than 1.2% at full load.


The 1.85-gallon gas tank holds more than enough fuel to keep the equipment running for up to seven hours at a 50% rated load. This is equally a remarkable 6.6 kilowatt-hours per single gallon. Boasting one the best fuel consumption rates and an equally relatively affordable price, the  WEN GN400i  a strong option. 



If you are going to camp outdoors, you will not bring a bulky generator with you! Instead, you would prefer lightweight and portable equipment that is easy to transport from one point to another. And the WEN GN400i doesn’t disappoint when it comes to weight and portability concerns.


Compared to its conventional open frame portable generators, this particular device weighs substantially less, offering easy maneuverability. Moreover, at only 66.1 pounds, the WEN GN400i has a highly lightweight design, another of its major selling points.


It is also worth noting that the design of this generator is an open frame, with the dimensions of 19.8 by 13.8 by 18.9 inches, providing stability and support and providing the possibility of raising it above the ground. However, despite its robust and rugged design, the WEN GN400i open frame generator has also been crafted with harsh environments and demanding outdoor use in mind.


Inverter Technology

In case you didn’t know, inverter technology is arguably the latest advancement as far as portable power generators are concerned. Smaller, quieter, and lightweight inverter generators use highly innovative technology to transform DC power into AC power with high frequency safely.


The process of changing electrical energy from DC to AC significantly eliminates any power fluctuations usually associated with traditional generators.


One of the significant benefits of inverter generators is they are fuel-efficient. An inverter generator can automatically adjust the engine’s speed, ensuring the generator only produces the exact amount of power needed for the job.


Thanks to its clean and quiet portable power, an inverter generator is safe to run sensitive electronics, including mobile devices, laptops, TVs, and computers parallel ready panel. Inverter generators are also revered for their somewhat lower carbon emissions, making them eco-friendly.



Unlike the other conventional power generators that are difficult to operate, the WEN 4000 Watt Inverter generator offers ease of usability. The control panel features light indicators that notify you anytime you have low oil and fuel levels than expected. The light indicators also let you know when the generator is overloaded and when the generator is ready for use.


Also, thanks to the built-in fuel gauge, the inverter generator allows users to promptly, conveniently, and almost effortlessly examine the gas levels. In addition, the fuel shutoff feature at its disposal turns off the fuel flow, allowing the generator to consume any remaining fuel from its carburetor before ultimately shutting off automatically.


This adds to its already remarkable efficiency and helps prevent any build-ups and blockages caused by stale fuel inside the generator. It helps significantly reduce maintenance and repairs while extending the unit’s lifespan.


The 4000-watt open frame inverter generator features overload protection, a low fuel automatic shutdown, automatic low oil shutoff, allowing you to operate and use the device with peace of mind. The WEN GN400i also comes with a detailed user manual intended to enable you to know and understand nearly everything you need to know regarding how to operate and use the device.



When purchasing a power generator, quiet operation is a great feature you would want to overlook. Unfortunately, one major issue with other generators of this caliber is how loud they can get. And this makes them somehow annoying to use, especially when you need quiet equipment for RV, camping, or even home use.


Thankfully, because of its impressive pure sine wave technology, the WEN GN400i is relatively quieter. And even at higher loads, its modern engine will operate at the lowest side of noise rating. With a noise rating of 76 decibels, this inverter generator is less noisy than a normal conversation.



As already mentioned, WEN has a reputation for manufacturing top-notch generators that feature excellent and performance-oriented features. And this particular one is its typical product. It is not only packed with lots of great features but is also relatively affordable.


The WEN is almost half as cheap as some of its immediate competitors but guarantees better performance. At below $500, the WEN GN400i open frame inverter generator is genuinely a bargain considering the features and the level of performance it brings on board.



We have already explained that this incredible device is designed with user-friendliness and safety in mind. First and foremost, it features a 212cc power engine that will automatically shut down when it runs low on either fuel or oil.


On the other hand, flipping its on/off button cuts the flow of fuel to the engine. This results in the consumption of the remaining fuel inside the device’s carburetor, implying that you won’t have clogged jets when you pull the generator out of storage.


The WEN 4000-watt open frame inverter generator has a control panel that houses the choke lever and a display that indicates overloads, low oil, and active loads. You can activate the eco-mode. The generator will automatically adjust its engine speed to match the current load, significantly minimizing fuel consumption.


Finally, The WEN GN400i generator  is both CARB-compliant and EPA-approved. It also has a spark arrester, making it suitable for use in forested places.




Also Read: Best Dual Fuel Generators [2022]

WEN GN400i Frequently Asked Questions (FAQs)

Are WEN generators any good?

WEN is a highly reputable American power tool and equipment producer that has been in operation for more than six decades. The company, WEN Products, was established in 1951 and prides itself in developing modern chainsaws, soldering devices, and wet sharpeners through its thorough research in random orbital technology.


However, the company expanded its production line to include all sorts of power tools such as drills, presses, and inverter power generators. Despite being reasonably affordable, WEN generators come packed with all the features homeowners need from a high-end power generator.


They are highly efficient and performance-oriented products that you won’t regret spending your hard-earned dollars on.


What can I power with this generator?

This generator is a highly versatile device that has enough energy for any hand tool. With 4000 watts available, it will have no problem powering even a four battery quick-charge station along with lighting and a few ac-powered devices. And because it has an inverter, the Wen GN400i generator can also be used to safely power household electronics.


How loud is the WEN generator?

At 67 decibels, this generator functions quietly and is less noisy than a normal conversation.


Which generator is better, WEN or Generac?

It is worth noting that these two are inverter generators and feature nearly the same features in terms of performance. However, in terms of power, this particular generator is slightly more powerful.


Wattage Demands

ApplianceStarting WattsRunning Watts
Furnace (1/4 HP)1000600
Sump Pump (1/3 HP)1300800
Washing Machine22501150
Window AC 13K BTU28001800
Well Pump21001000

Conclusion on WEN GN400i

The WEN GN400i  is lightweight, easy to use and comes equipped with nearly every essential feature you would want for powering your necessary devices.


The WEN GN400i  lacks the run time of its competition.. However, it’s an affordable option that can provide stable power for most electronics and small to medium size home appliances. 


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