Generac GP3500iO Portable Generator Review

Generac GP3500iO Portable Generator is a reliable and powerful inverter generator in the skin of a conventional generator. Its PowerRush Technology provides a 50% more starting capacity to support tools and motor-driven appliances. Its True Power Technology delivers stable and clean power, and it is reasonably quiet and light in weight. Also, GP3500iO comes with a 3-year limited warranty.

Generac GP3500iO portable power station


Generator Type: Generac GP3500iO is a gas-powered open frame inverter generator. It is an RV-ready unit, so it is highly suitable for powering your recreational vehicles. But, you can also use it at home, office, or a construction site. Moreover, it is widely used by campers and tailgaters.

Portable: It is 25% lighter than generators of its kind. Its open-frame design, lightweight, and compact size make it a portable machine. If you need to move the generator, two persons can easily carry and move it.

Its weight is 74.3 pounds, and it is 19.3 inches in length, 16.9 inches wide, and 16.4 inches in height.

Emissions: It is a CARB (California Air Resources Board) compliant generator. It means Generac GP3500iO is an environmentally friendly unit that strictly follows the emission standards set by CARB.

Starting Mechanism: A simple pull-start mechanism turns on the generator quite easily.

PowerDial: It is a simple and easy-to-use dial featuring three operation settings, including Choke, Run, and Off.

Choke helps the carburetor to extract more fuel than the incoming airflow to smoothly start the cold engine. At run setting, the generator slowly eliminates the use of choke to run normally. And the off function shuts down the fuel supply so that the engine can run with the remaining fuel in the carburetor and then shut off automatically.

PowerRush Technology: Generac GP3500iO is featured with an Advanced PowerRush Technology that gives over 50% more starting capacity for tools and motor-driven appliances.

It has a 212cc, 4-stroke Generac OHV engine, which offers 3500 starting watts and 3000 running watts.

True Power Technology: Its True Power Technology provides clean and stable power with minimal levels of harmonic distortion. It comes with a less than a 3% THD (Total Harmonic Distortion) rating. This THD rating allows you to freely power your sensitive electronics such as smartphones, computers, laptops, and others.

Parallel Capability: It is also a parallel capable generator that allows you to double the output power by connecting another GP3500iO with the help of a parallel kit. But the parallel kit doesn’t come with the generator, so you have to purchase it separately.

Tank Size and Runtime: The fuel tank capacity of this unit is 2.37 gallons. It consumes 0.22 gallons of gasoline per hour to give 11 hours of runtime at a 25% rated load and 8 hours of runtime at 50% rated load.

Economy Switch: This inverter generator also comes with an economy switch. It saves fuel, increases the lifespan of the engine, and reduces noise levels. It auto-adjusts the engine speed to match the requirement of the load applied.

Operational Sound: Generac GP3500iO is 50% more quieter that makes it suitable for use in noise-sensitive environments.

Power Outlets: It is equipped with three AC outlets and two DC outlets.

The AC outlets include two 120 Volt 20 Ampere (5-20R) household outlets and one 120 Volt 30 Ampere (TT-30R) RV-ready outlet.

The DC outlets include two 5 Volt USB ports that you can use to power your electronic devices.

Hour Meter: The power panel also features an hour meter that shows the lifetime run hours of the generator.

Indicator Lights: Three indicator lights showing the generator is ready to use, it is low on oil, and it is under extra load.

Safety Features: It comes with overload protection and automatic low oil shutdown features.

Warranty: Generac GP3500iO has a 1-year limited commercial warranty and a 3-year limited residential warranty.

What Comes Inside the Box? Things that come with this generator include a user manual, engine oil, tool kit, and an oil funnel. 

Generac GP3500iO vs. Champion 100302 vs. Westinghouse iGen4200



  Generac GP3500iO Champion 100302 Westinghouse iGen4200
Peak/Rated Watts 3500W/3000W 4000W/3500W 4200W/3500W
Tank Size 2.37 gal. 2.9 gal. 2.6 gal.
Runtime 11 hrs (1/4 load) 17 hrs (1/4 load) 18 hrs (1/4 load)
Noise Not Mentioned  64 dBA 60 dBA
Starting Mechanism Recoil Recoil Recoil
Weight 74.3 lbs. 81.6 lbs. 82 lbs.

My Opinion:

Pros: Generac GP3500iO is a powerful RV-ready inverter generator. It is light in weight, quiet for its power, and has a sturdy framework for easy carrying. It produces clean output power so that you can run your sensitive electronics. The availability of both AC and DC outlets makes it versatile. Also, GP3500iO is easy to use and maintain.

Cons: It doesn’t come with wheels, and its runtime is relatively low.


Is Generac GP3500iO a transfer switch ready unit?

No, it is not a transfer switch ready unit. It doesn’t feature the L14-30R outlet that makes the generator transfer switch ready.

Can you draw power from both AC and DC outlets at the same time?

Yes, you can draw power from both the 5-20R AC outlets and USB ports at the same time.

Can you connect GP3500iO in parallel with GP2200i?

No, you cannot connect GP2200i with GP3500i to generate more power. It can only be connected with the same GP3500iO.

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