WEN GN400i RV-Ready 4000-Watt Open Frame Inverter Generator, CARB Compliant, Black/orange
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Availability:
In Stock.
Arrives
Jun 19 – Jun 21
Style: 4000W Inverter
Features
- Dimensions: 19.8" L x 13.8" W x 18.9" H | Weight: 66.1 lb.amperage : 26.6 amps
- Generate clean power to safely operate sensitive electronics such as phones, tablets, televisions and computers
- Parallel-ready panel allows you to connect any two WEN inverter generators for increased wattage output
- 212cc 4-stroke CARB-compliant OHV engine produces 4000 surge watts and 3500 rated watts
- Includes two 120V NEMA 5-20R receptacles, two 5V USB ports, one 120V RV-ready TT-30R receptacle
Description
Remember when you had clean and quiet portable power? The WEN 4,000-Watt Inverter Generator provides clean energy, free of voltage spikes and drops for safe use with laptops, phones, and other sensitive electronics. Our 212cc 4-stroke OHV engine produces up to 4000 surge watts and 3500 rated watts of power. Designed to mirror a pure sine wave, this generator limits total harmonic distortion to under 0.3 percent at no load and under 1.2 percent at full load, making it safe to run sensitive electronics. Our ultra-efficient 1.85-gallon tank provides over 7 hours of half-load run time. The fully-packed panel comes equipped with two three-prong 120V NEMA 5-20R receptacles, two 5V USB ports, and one 120V RV-ready TT-30R receptacle. Maximize fuel economy by engaging the eco-mode switch. This allows the generator's engine to automatically adjust its fuel consumption as items are plugged into and unplugged from the panel, preventing the unnecessary usage of gasoline. Need more energy? Easily link up two generators using a WEN Parallel Connection Kit (sold separately) in order to share wattage amongst multiple units. Low-oil and low-fuel automatic shutdown combine with the built-in overload protection and indicator lights to safeguard both your generator and your electronics from damage. And because its a WEN product, your open frame inverter generator comes backed by a two-year warranty, a nationwide network of skilled service technicians, and a friendly customer help line, all to make sure you remember WEN.
Brand: WEN
Wattage: 4000 watts
Fuel Type: Gasoline
Power Source: Gas Powered
Recommended Uses For Product: Residential, Recreational
Voltage: 120 Volts
Output Wattage: 4000 Watts
Special Feature: Portable
Included Components: Inverter generator with two 120V NEMA 5-20R receptacles, two 5V USB ports, one 120V RV-ready TT-30R receptacle See more
Color: Black/orange
Wattage: 4000 watts
Fuel Type: Gasoline
Power Source: Gas Powered
Recommended Uses For Product: Residential, Recreational
Voltage: 120 Volts
Output Wattage: 4000 Watts
Additional Features: Portable
Engine Type: 4 Stroke
Ignition System Type: Electronic
Tank Volume: 1.85 Gallons
Engine Displacement: 212 Cubic Centimeters
Total Power Outlets: 5
Current Rating: 30 Amps
Engine Power Maximum: 4 Kilowatts
Starting Wattage: 4000 Watts
Running Wattage: 3500 Watts
Frequency: 50 Hz
Runtime: 7 hours
Brand Name: WEN
Included Components: Inverter generator with two 120V NEMA 5-20R receptacles, two 5V USB ports, one 120V RV-ready TT-30R receptacle
Model Name: RV-Ready
Model Number: GN400i
UPC: 044459991694
Manufacturer: WEN
Global Trade Identification Number: 94
Manufacturer Part Number: GN400i
Unit Count: 1.0 Count
Item Type Name: 4000-Watt Open Frame Inverter Generator, CARB Compliant
Item Dimensions L x W x H: 19.8"L x 13.8"W x 18.9"H
Color: Black/orange
Material Type: Metal (Likely Steel/Aluminum), Plastic, Rubber
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Jun 19 – Jun 21
This item is non-returnable:
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
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Top Amazon Reviews
Style: 4000W Inverter
I was looking for a emergency home generator and looked high and low for one that used inverter technology. I was concerned as a neighbor bought a generator without a inverter and ruined a refrigerator and TV beyond repair. His generator was a 4000 watt unit at the same price point as the WEN. While I can’t speak for the construction the WEN appears better finished and more solid. Both weigh about the same. Both are open framed. The setup is like any new engine, read the manual. I did use Pennzoil Ultra 10/30 Synthetic oil, Premium gas with one ounce of Lucas Oil Treatment as I had good luck with the combo in my lawnmower, car and motorcycle. Absolutely no problems with set up and breaking in the WEN. There is a grounding wire tap on the control panel which I did attach to ground the generator as it was close to our main water inlet. Grounding the generator makes sense as electronics are extremely sensitive! An ounce of prevention now can save hundreds or thousands latter. My installation is in a home. I know nothing about use in RV’s or campers, but would think a ground makes sense there too. For me the WEN is an affordable and so far reliable Inverter generator! I think it’s a steal! Thinking of buying another so as not to stress out a single unit in long periods of use. Addendum: It’s been over a year and half now and the WEN is still doing its thing without problem. I installed an Hour Meter and accumulated 247 hours. I’ve changed the oil every 48 hours, installed a magnetic drain plug and a new spark plug if it look fouled. I still use Lucas Oil Treatment one ounce at each oil change. I bought a second WEN and now run them in parallel without any problems. The pair can run a 12,000btu a/c, full size refrigerator and a 1000 what microwave. I do turn the a/c to fan when using the microwave as not to stress the generators. No failures, starts with one or two pulls, very little smoke and have not noticed any change in noise levels. It’s easier to move two 60+ pound generators than one 8,000 watt unit. My volt meter shows a steady output. With load shows 6,700 watts steady and peak of 7,250 watts in parallel and 3,320 watts as a single unit steady state.
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Reviewed in the United States on June 11, 2022 by alan fenick
Style: 8750W + Electric Start
WEN GN875i open frame inverter generator Unit is loud. WEN technical/customer service support is available in The States via an 800 telephone number from the owner’s manual though wait queue on my four calls averaged twenty minutes. No ticket number was assigned. However, that didn’t seem to be a problem on subsequent calls. Perhaps my telephone number was logged and used to identify me and access my previous conversations. NOTE: WEN uses an automated system to field your call offering the option of holding, noting the number of people queued in front of you, or leaving your telephone number for a call back. The convenience of leaving a call back number could be outweighed by the slower response of the call back, which in my case was well over 24 hours, depending on your circumstances. Product and return knowledge varied from excellent to poor depending on the representative I spoke to. The first unit arrived on time enclosed in a plastic bag inside of a single walled corrugated cardboard carton lined on all six sides with ¾” foam. The carton had a puncture and resulting 2” tear. Total wt. of the shipment was 147 lbs. per the FedEx label. I found the packaging to be inadequate. The tubular frame was bent near a wheel axle mount point resulting in the axle tracking about 15° off center. I used a couple of 4x4’s two screws and a bottle jack to return the frame to its original position, leaving only a dent and scuff mark from the impact that caused the damage. I found tipping the unit on its side facilitated the removal of the shipping brackets. Final assembly, i.e., axles, wheels, feet, handle and connecting the ground terminal wire to the battery was straight forward using only the supplied tools and owner's manual. After engine break in – 30W oil, no load, one hour run time: The engine coughed and died each time a larger load demand was called for, e.g., well pump and miter saw, though it had no problem with the fridge compressor or lights, tv, ceiling fans, etc. After diagnosing the trouble as a potentially bad carburetor stepper motor, WEN support told me to contact Amazon to make return arraignments. However, when I pulled up my order on Amazon I found requests for return directed me to the seller, WEN, as Amazon does not allow product with oil and/or gasoline to be sent to them (even residual amounts). A call back to WEN had me going back and forth with one of their tech/svc people. He telling me he had no way of helping with a return since Amazon made the sale. Me telling him that Amazon clearly states they do not allow items with gas and or oil in them to be sent to any of their facilities and to contact the seller. He telling me Amazon puts that up to deter returns, but if I actually spoke to an Amazon representative they’d give me a return code to use. Me telling him (again) Amazon clearly states, for safety reasons, they do not allow this type of product sent to them. He putting me on hold. He coming back on the line and offering me the option of sending the unit to WEN outside of Chicago or to carry it to a local -to me- authorized WEN repair outfit. I chose the former. He emailed me a return label. Unfortunately, I did not realize that I needed to contact the carrier for pickup, thinking that the creation of the label notified the carrier (FedEx Ground) of the need for a pickup. Another call to WEN cleared this up for me. Exactly one week later, WEN tech/svc called telling me they did not have the parts necessary to repair the unit I had sent them, but offered to either cannibalize a new unit to make the repairs or to simply send a new unit. I chose the latter. A week later, the replacement unit arrived. Again, there was a puncture through the carton, but only minor cosmetic damage was the result. The oil fill plug was not threaded back into the engine tightly enough at the factory, causing residual oil to coat a good portion of the unit. Although the handle is shipped inside of bubble wrap it is put in an opening between the engine and inverter. I’m assuming, sharp edges inside of the unit cut the foam on the handle in two places. The same damage occurred in the original shipment as well. Two cuts on the foam handle. This time I tested the generator after engine break in but before putting the wheel kit, feet and handle on by spinning up a miter saw that draws 18 AMPS at start up. The engine and generator performed flawlessly. I subsequently put the wheels and handle on, grounded the unit and plugged it into a Reliance 10 circuit 7500W transfer switch (excellent product btw) and have run the fridge, well pump, three ceiling fans, a blender, basement, kitchen and bedroom lights and an air fryer simultaneously. When demand is called for the engine and generator immediately respond. I couldn’t be more pleased. The unit is loud, reading 82dB at 20’ using an uncalibrated freeware app on my iPhone. As to packaging, UPS Small Parcel and FedEx Ground have a 150 lb. weight limit which suggests more robust packaging is not an option (GNi875 shipping weight +/- 147 lbs) for WEN, unless they ship via a more expensive mode. The tech/svc person I dealt with said that one in ten of the GN875i units were being damaged in transit; so chronic a problem that they were offering credits up to $100.00 on units that arrived damaged. I’m on the East Coast in the USA the unit shipped from California, so my units probably experienced more transfers than most do.
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Reviewed in the United States on November 18, 2021 by John
Style: 4000W Inverter
FUNCTION- Pros: I bought this for my RV and for backup power in case of a power outage. The gn400i has a lot of bang for the buck. At 4000 peak/3500 rated watts, it should service my purpose well. Love having the 30 amp receptacle. Love the fact it is an inverter generator. It seems to run strong, pushing a 1500 watt heater without missing a beat....and that was in eco mode. This generator is also very economical. My 7+ hours of run time was on a 2/3-3/4 full tank. A full 1.85 gallons should last a long time. At 66lbs it is also light enough to move around. I can lift it into the bed of a truck with ease. Cons: While perfect for an RV, it's a little weak for running a household. I'll be plugging and unplugging a whole bunch during an outage. NOISE- Let's address the elephant in the room Pros: At least it isn't as loud as a Harley??? If you have an RV, then you know the a/c's are extremely loud and will drown out almost anything. I don't think noise will be an issue except maybe with a neighbor. I also have a long extension cord, so I can move the generator far away from the RV to reduce noise. Cons: This generator is LOUD. Period. I read somewhere that it was rated at 67dba. Where? It isn't in the manual. When I first started this thing, my first thought was there is no way this is in the 60's. According to my phone app, it was over 80dba next to the unit and between 72-76dba at about 20 feet. There is very little difference in noise between eco/regular mode. MAINTENANCE/BREAK-IN- Pros: This open frame generator is SO much easier to work on than my last Champion 2000 inverters. Everything is more accessible. Even with the panels off on the Champions, space was very limited for you hands. Wen was very thoughtful when designing the GN400i for service. Oil changes are easy....keep reading to see why that is important. And the fact they include an elevation kit and a handy dandy funnel is a real plus, too! Cons: After prepping the unit with Mobil 1 5w-30, I ran for 30 minutes and did an oil change. The magnetic dipstick was caked with shavings and the oil itself was black with lots of metallic specks. I've had motorcycles, atvs, lawn mowers and 3 other generators. I've never seen oil that dirty. I ran another 4-5 hours and changed the oil again. Again, it was black but at least without the metallic specks. After 7 hours, the oil looks decent but the dipstick is still coming out black. I'll likely change oil again at 10-15 hours. All this to say, if you buy one of these plan on 3-4 oil changes during the initial break-in to flush the engine prior to regular use. EDIT: After sitting unused for 6 months (Sep 2021), fired right up. Runs one of my 15k btu a/c's in my 5th wheel just fine (one unit, won't run both). Still happy. EDIT2: First Power Outage since I purchased. Pulled the generator out after sitting another year in storage (Oct 2022). Started on the 5th pull. Purred like a kitten while running my 2 refrigerators. EDIT3: Dry camping trip coming up. Got out to make sure it would fire up. Started on 2nd pull. (April 2023). Strongly recommend Stabil and running the fuel out of the carb. Put about 30 hours on it. Ran like a champ! Edit: Feb 2025. Haven't had much reason to use the genny over the past 22 months. Decided I would run it a while this morning. Started on the 5th pull. Running a space heater. Purring like a kitten.
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Reviewed in the United States on March 3, 2021 by JB
Style: 4500W Dual Fuel + CO Alarm + Electric Start
We bought this generator for my husband’s mobile detailing setup, and it has been working great. It has strong, steady power and starts quickly with the electric start. The build quality feels solid, and the wheels make it easy to move when needed. Assembly was simple and everything was ready to use right away. I added photos and a video to show how it runs. The noise level is reasonable for this size, and the generator handles all of his detailing equipment without any issues. It feels durable, has good capacity, and the features are very straightforward. A dependable, well-made generator that works exactly as expected.
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Reviewed in the United States on November 22, 2025 Reviewed in the United States on November 22, 2025 by Enia
Style: 8750W + Electric Start
For the Wen GN875i - As of Nov. 2024 they seem to have resolved packaging issue and mine arrived undamaged. The manual is pretty good. I added one quart of 5W-30 Synthetic and that seemed to fill it up. The manual said the starting battery needed to be connected and it was at the terminals but there is a plug tie-wrapped and tucked up inside that I missed so when the electric start didn't work I thought it was because the battery was dead. Later, when I looked closer, getting ready to charge it I saw the plug. Once connected it worked. The generator is very easy to start if you follow the procedures printed on the card attached to the unit. After filling with non-ethanol gas, opening fuel flow, turning on the run switch and giving it choke, it almost started the first pull. It started and ran non-stop on the second pull. Not sure how they made it so easy to pull-start. I didn't really need the electric start. I have never broken in a small gas engine on any other gas-powered equipment but I followed break-in procedures for this 13 HP 420cc engine using two space heaters, a box fan and an electric charcoal starter. No load the first hour, then small loads the second hour, then varied loads totaling less than half the rated power. During the first hour there were regular pops/sputters that I think was caused by fuel blowing past the piston rings and backfiring in the exhaust. The backfires subsided in the second hour and it was running very smooth after 4 hours. The purpose of the break-in is to properly seat the piston rings. I am glad I ordered the WEN magnetic oil dip-stick for $10 to use for the break-in. It collected a blob of fine metal powder during the 8-hour first run. Eco-Mode was good for smaller loads but the engine ran at full rpm with Eco on or off with a 40%+ load. A full tank of gas (4.2 gallons?) lasted more than 7 hours with light-medium loads. Changing the oil was easy but I had to set it up on wood blocks to get it high enough to flow into a small container. At 135 pounds it is very heavy but the wheels and handle that you attach to the generator (assembly required) allow it to be moved around without any problem even going up a step at a doorway. There is no way one average person could dead lift this into a truck or trunk of a car but a ramp would work for a pickup. I compared this unit to the same size inverter generator at Harbor Frt. and they appear VERY similar in overall construction and features. Maybe the same factory? The WEN was $300 less and I feel like it was a great value. You can tell that it was designed and manufactured with quality in mind. Haven't tried near maximum loads yet but I am optimistic.
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Reviewed in the United States on November 14, 2024 Reviewed in the United States on November 14, 2024 by S. Grant
Style: 8750W + Electric Start
Thought the reviews with the bent frame were anomalies, but sure enough, I got a slightly bent frame, otherwise everything else looks good. I contacted WEN to tell them their factory is bending frames then boxing the generator. They told me to contact Amazon about either a return or a possible discount. I did and they were fantastic. Offered a very generous discount or a return with a pickup at the house, I would not have to cart it back to UPS. I opted for the discount. I haven't even turned it on yet, but I can say the machine is sleek and compact. Looking forward to putting it through it's paces of engine breaking in to finally back feeding my house panel to see it I can support a whole house operation. I will edit this review as I get more info. Amazon CS rocks. Update, I put the unit through a 5 hour break in. Replaced the break in oil with 5-30 full synthetic. Put in an NGK iridium spark plug. Then I powered the house and tried to start the 4 ton AC unit and it would not bring it up to speed. The generator overload kick out after about 10 seconds. I really wanted this to work, so with the bent frame issue I considered returning it because of this to get a bigger unit. Amazon said that if you put oil and fuel in it they could not take a return. Warranty through the company was an option. So I decided with the discount I received for the bent frame, I bought and installed a soft start for the AC compressor. The generator easily started and ran the AC unit on top of an already base load of about 2000 watts. I had it loaded to about 6800 watts and it ran flawlessly. I love the compact footprint. Fits under my workbench with a cover on it. I also decided to get a propane conversion kit. Runs on propane without a hitch, also to 6800 watts. All in all this unit is a great buy compared to other inverter units of the same size, and if you get a bent frame, if it's not too bad you can work the bend out with a pry bar and have extra cash from a discount for gas or a nice cover. The cover I got for this is very well made with great customer support. Links below to the cover and propane kit. https://www.amazon.com/Motor-Snorkel-Generator-Conversion-Generators/dp/B01M4RZMIS/ref=sr_1_1?crid=3LKYPGTYGL9WD&keywords=motor+snorkel+tri+fuel+conversion+kit&qid=1666237249&qu=eyJxc2MiOiIxLjg5IiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ%3D%3D&sprefix=motor+snorkel+%2Caps%2C89&sr=8-1&ufe=app_do%3Aamzn1.fos.18630bbb-fcbb-42f8-9767-857e17e03685 IGAN cover https://www.amazon.com/gp/product/B0817FJRJD/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 I'm just a regular person, I received no compensation for this review.
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Reviewed in the United States on October 9, 2022 Reviewed in the United States on October 9, 2022 by Bob S
Style: 8750W + Electric Start
I’ve had this generator since 2021. It’s been great. No issues other than the starter switch went out a few months back. Ordered a new one from WEN and easily replaced it. I highly recommend this generator.
Reviewed in the United States on May 5, 2026 by Gary
Style: 4000W Inverter
Living in rural PG&E territory, unfortunately, so a generator is now a good thing to have in case of emergencies. I was looking quite awhile for a 4000-ish peak watt generator and stumbled across this incredible deal and purchased right away. One good tip for generator noobs: read the manual and follow the proper maintenance, startup and shutdown procedures. If you don't, you'll run into issues in the future. Once you know the tips, startup and shutdown is a cinch. One nice thing is it comes with a sparkplug socket, a wrench, a funnel, and high elevation carb kits. You can tell they took care in ensuring people use their products properly to get the most value out of them. I have not used this for an actual power outage, but I tested it on a couple things. I hooked up a chest freezer, a window AC unit, and our gas furnace all at once. Noticed no bog down whatsoever. It seems this will work great in a pinch. I would recommend you buy the RV adapter with a split that way you have more plugs to distribute the amps being pulled. They add up quickly. The weight of this is great. You can carry it by the frame for short distances or could put it on a hand truck no problem since it's pretty small. It is heavy enough where my wife would not be able to carry though and if it's hot you probably don't wanna move with for awhile. Cons: I don't think this is as quiet as advertised. With the Eco mode it becomes a little quieter, but with a lot of watts running it's nearly as loud as a traditional generator. I wish the fuel tank were a little larger as well to be able to get 10 hours out of it. I have seen reviews of people getting more than 7 hours though, so we'll see. A smaller tank does make it lighter though. Conclusion: no, this is not as nice as a Honda generator which would cost 4x what this one costs. If that's your expectation, buy a Honda. You know what you want. It does seem well built though, and if you take of it, it will take care of you. It's the best value for an inverter generator I have seen anywhere! Buy it, and if you hate it, empty your savings account on a Honda so you can brag to your buddies around the beer keg.🤣
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Reviewed in the United States on November 17, 2019 by Josh