Firman WH03662OF - 3650/4500W Dual Fuel Open Frame Inverter Generator With Electric Start
The Firman WH03662OF is a portable open frame dual fuel inverter generator with a rated wattage of 3,650 W and a starting wattage of 4,500 W. (Read full specs)
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Amazon | Price history for the Firman WH03662OF |
|---|
| Highest Price $1,259.99 Lowest Price $1,155.51 Current Price $1,259.99 |
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Description
Zoom on the Firman WH03662OF
In short, the Firman WH03662OF is a portable inverter generator adequately designed for:
- RV travellers looking for even more independence
- People occasionally participating in sporting competitions, open-air performances and outdoor festivals
- Homeowners who want to be able to use the most necessary devices in their household, even during a blackout
- Camping and tailgating hobbyists looking for a portable power source
In the forthcoming sections, you'll delve into its power characteristics, the various outlets it offers, its overall portability, and the additional features it boasts.
Power & Run Time
The Firman WH03662OF
The dual-fuel technology of the Firman WH03662OF allows for an output of 120V and provides superb power and versatility. If gasoline-powered, the device provides a running wattage of 3,650W and a starting wattage of 4,500W. If propane-powered, it gives 3,300 rated watts and 4,100 starting watts. Furthermore, its parallel capability (parallel kit not included) allows power output to increase when connected to another similar or compatible unit, ensuring expanded energy capacity and reliability for various applications.
With a noise rating of 69 dBA (less noisy than background music), the inverter generator features a standard recoil pull-rope starting mechanism, but also a hassle-free and practical electric starter (battery included).
With a fuel capacity of 6 gallons, the WH03662OF can operate for up to 25 hours using gasoline (fuel consumption around 0.24 GPH), or for up to 19 hours (on a 20 lbs tank - propane consumption around 0.25 GPH) using propane.
With a <3% Total Harmonic Distortion (THD), the WH03662OF delivers a clean sine wave—essential for safeguarding your delicate electronics when plugged into its AC outlets.
Outlets
The control panel is equipped with the following 4 AC outlets:
Moreover, it presents 3 DC outlets: there's two 5V USB ports (USB-A) with which charging of electronics like mobile phones and tablets is made convenient and a 12V 8A (cigarette lighter style) receptacle with which you may charge your batteries with ease.
For RV owners with a 50-amp service, this Firman unit is RV-ready, boasting a 14-50R outlet.
Important note: The 14-50R outlet is normally 120/240V. However, this unit does not produce 240V. This outlet is here for your convenience, but should only be used to power 120V appliances. In addition, since the generator provides a maximum of 3650 running watts, it will not be possible to draw the full 50 amps from the outlet.
Portability
At L24.5 x W24.1 x H23 in, the traditional open frame structure of the Firman WH03662OF ensures stability while facilitating convenient maintenance access to components and promoting air cooling. The featured design is ideal for the outdoors and all tough environments.
While the generator is considered to be technically 'portable' (in the sense that you can move it), manually lifting and transporting it may be challenging, due to its high weight of 119 lbs. Nevertheless, the restricted maneuverability is counteracted by its set of wheels (⌀9") and its folding handle, enabling easy shifting once the generator is set in place.
Features
The WH03662OF's control panel
The control panel of the WH03662OF is equipped with a convenient meter, providing voltage, frequency, and lifetime hours data, aiding in monitoring its status and activity.
In addition to this info, the device's light indicators will illuminate to indicate if the generator is ready, the oil level is too low and the generator is on overload.
Equipped with a built-in fuel gauge, the inverter generator facilitates swift gas level checks.
As for its security measures, the device features an overload protection (circuit breaker) and an automatic low oil shut-off, letting you use it with a peace of mind.
The WH03662OF also benefits from Firman’s CO Alert carbon monoxide shutdown, which automatically shuts down the engine when harmful levels of carbon monoxide accumulate around the generator or a CO Alert fault occurs.
Beyond the standard documentation and an owner's manual (opens in a new tab) to assist with setup, the Firman WH03662OF ships with supplementary accessories: propane hose, tool kit, battery charging cables, oil, funnel and RV adapter.
The Firman WH03662OF versus other generators
The following charts are provided to give you an idea of how some of the key specs of the Firman WH03662OF compare to inverter generators of similar power (between 3500 and 4500 W).
- With a weight of 119 lbs, the Firman WH03662OF sits in the heavier end of the spectrum among inverter generators rated from 3500 to 4500 watts. if you wish to prioritize weight, the WEN 56432iX is one of the top contenders in its power category, weighing only 52.9 pounds.
- When comparing it to devices with a similar running wattage, this inverter generator's lowest noise level of 69 dBA puts it alongside the noisier units. If you value reduced noise levels, the Westinghouse iGen5000DF could be worth considering. It's one of the quietest generators in its power range, rated at 52 dBA.
- With up to 25 hours of runtime at 25% load, the WH03662OF provides a one of the highest run times when compared to similarly powerful inverters.
- The run time is important, but also hugely depends on the capacity of the fuel tank and doesn't mean much if we don't talk about fuel consumption as well. This inverter generator doesn't excel in fuel efficiency when compared to others of its kind: it consumes approximately 0.24 GPH at a 25% load. If gasoline efficiency is at the top of your list, you may want to have a look at the Champion 201319, which has great fuel efficiency, with a gas consumption of only 0.16 gallons per hour.
Price comparison
As you can see from these interactive charts, when compared to other 3500-4500W dual fuel inverter generators, the Firman WH03662OF is on the average side of the price range.
Therefore, this generator nicely fits in the expected budget for this kind of product.
The bottom line
- In the expected price range
- Dual fuel
- CO Alert technology
- Several accessories included
- RV adapter included
- Electric start
- Parallel capable
- Inverter
- High run time
- No 240V output
- No remote start
- On the heavy side (119 lbs)
- On the noisy side (69 dBA)
- Low fuel efficiency
Do you own the Firman WH03662OF and agree (or disagree) with these strengths and weaknesses?
Let us know and write your own review.
Features and Specifications
| Inverter | Yes |
|---|---|
| Parallel capable | Yes, cable not included |
| RV ready | No |
| Fuel | Dual Fuel (gasoline/propane) |
| Engine | 208 cc OHV 4-stroke, cast iron sleeve |
| Starting system | Recoil, Electric |
| Warranty | 3 years |
| Voltage | AC: 120V 60 Hz, DC: 12V |
| Gasoline | Propane | |
|---|---|---|
| Running watts | 3,650 W | 3,300 W |
| Starting watts | 4,500 W | 4,100 W |
| Running amps | 30.4 amps | 27.5 amps |
| Peak amps | 37.5 amps | 34.2 amps |
| Run time @50% load | Unknown | Unknown |
| Run time @25% load | 25 h | 19 h |
| GFCI outlets | No |
|---|---|
| Covered outlets | Yes |
| Automatic Voltage Regulation | Inverter |
| AC outlets |
|
| DC outlets | 2x 5V USB port (USB-A) 1x 12V 8A (cigarette lighter style) |
| Data center | VFT |
| Indicators | Low oil, overload and output ready |
| Fuel tank | Steel, 6 gal |
| Fuel gauge | Yes |
| Weight | 119 lbs |
|---|---|
| Approx. dimensions (L x W x H) | 24.5 x 24.1 x 23 in |
| Noise (lower limit) | 69 dBA |
| THD | < 3% |
| Compliance | CARB, EPA, ANSI/PGMA G300-2023 |
| Security | Low oil and overload protection, CO monitoring |
| Spark arrestor | Yes |
| Neutral | Floating |
| Accessories included | Oil, funnel, tool kit, propane hose, RV adapter, battery charging cables, battery, and wheel kit |
| Country of origin | China |
| Series | Whisper, Hybrid |
| UPC | 840876136621 |
We've taken extra care to research and verify each of the specifications above. That said, occasional mistakes or omissions are still possible. If you spot any missing or inaccurate information, feel free to suggest a correction so we can address it.
About FIRMAN Power Equipment
Founded in 1999, Firman Power Equipment is a company with a short, but established history in the power equipment industry. Based in Arizona, the company offers an immense range of products, including power tools, automotive equipment, storage utilities, work wear, but most importantly, a wide selection of generators of all sizes, designs and outputs. Interestingly, Firman is a wholly owned subsidiary of the China National Machinery Industry Corporation - a somewhat well renowned company in China and acts as a de facto distributor of their products in the US.
Warranty Information
The Firman WH03662OF is covered under a warranty for up to 3 years. This warranty may be limited and may not cover all parts of the generator.
For more information about the warranty of Firman generators, please consult Firman's warranty policies (opens in a new tab). Alternatively, you can also contact their Customer Support: 1-844-FIRMAN1 (844-347-6261).
Questions & Answers
What can it power?
| Item | Running Watts | Starting Watts | |
|---|---|---|---|
| At home | Refrigerator (energy star) | 192 | 1192 |
| Hair dryer | 1800 | 1900 | |
| Washing machine | 900 | 1650 | |
| Cell phone charger | 20 | 20 | |
| Total | 2912 W | 3912 W | |
| For camping | Radiant heater | 1300 | 1300 |
| RV refrigerator | 180 | 600 | |
| RV AC (11,000 BTU) | 1010 | 1600 | |
| Blender | 400 | 850 | |
| Cell phone charger | 20 | 20 | |
| Total | 2910 W | 3500 W | |
| For work | Grinder | 1400 | 2500 |
| Demolition hammer | 1260 | 1260 | |
| Electric fence (25 miles) | 250 | 250 | |
| Total | 2910 W | 4010 W |
Couldn't find the right answer for you? Ask your own question.
