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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Description
Zoom on the Firman WH03662OF
In a nutshell, the Firman WH03662OF is a portable inverter generator mostly geared towards:
- RV travellers who wish to upgrade their experience to another level
- People occasionally participating in outdoor fairs, festivals or events
- 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 following paragraphs, we shall explore the power characteristics, available outlets, portability, and any additional features of the device.
Power & Run Time
The Firman WH03662OF
The Firman WH03662OF, equipped with dual-fuel technology and delivering 120V, ensures both power and versatility. Running on gasoline, it delivers a running wattage of 3,650W and a starting wattage of 4,500W. On propane, it provides 3,300 running watts and 4,100 starting watts. In addition, the device is parallel capable (parallel kit not included) and thus, can be linked to a similar or compatible unit for added power.
Featuring a noise rating of 69 dBA (less noisy than background music), the inverter generator is equipped with both a conventional pull-start mechanism and a user-friendly and efficient electric starter (battery included) for starting.
The WH03662OF, with a fuel capacity of 6 gallons, reaches a run time of up to 25 hours utilizing gasoline (fuel consumption around 0.24 GPH). Alternatively, it can reach a run time of up to 19 hours (on a 20 lbs tank - propane consumption around 0.25 GPH) with propane.
The WH03662OF produces a clean sine wave: thanks to a <3% Total Harmonic Distortion (THD), your sensitive electronics can be safely plugged in the AC outlets.
Outlets
The control panel includes the following 4 AC outlets:
Additionally, it features 3 DC outlets: there's two 5V USB ports (USB-A) allowing you to conveniently charge electronics such as mobile phones and tablets and a 12V 8A (cigarette lighter style) receptacle providing easy battery charging capabilities.
If your RV requires a 50-amp service, consider this Firman unit RV-ready, as it includes 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 standard open frame design of the Firman WH03662OF delivers stability alongside easy maintenance access to components and good air cooling. The design is ideal for rough environments and demanding outdoor use.
While weighing 119 lbs, the generator is classified as 'portable,' indicating its mobility, albeit its heftiness may limit portability in specific situations. Despite the restricted maneuverability, its set of wheels (⌀9") and its folding handle provides a solution, allowing for convenient shifting once the generator is positioned on the ground.
Features
The WH03662OF's control panel
The WH03662OF's status and activity may be monitored conveniently via the control panel, as it features a convenient meter, which displays voltage, frequency and lifetime hours.
In addition to this info, when the generator is ready, the oil level is too low and the generator is overloaded, you will be informed by the featured light indicators.
The inclusion of a built-in fuel gauge in the inverter generator streamlines gas level checks for quick and convenient assessments.
As far as security is concerned, the generator can be used with a peace of mind, as it features an automatic low oil shut-off and an overload protection (circuit breaker).
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.
Apart from the typical documentation and an owner's manual (opens in a new tab), which lets you start it right away, the Firman WH03662OF also is packed along with the following accessories: oil, RV adapter, propane hose, funnel, battery charging cables and tool kit.
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).
- As its dry weight is 119 pounds, the Firman WH03662OF is one of the heavier of the inverters which can generate 3500 to 4500 running watts. If weight is an important consideration for you, the Genmax GM4600iAEFIC stands out as one of the top contenders in this power category, with a dry weight of 58.4 pounds.
- When compared to devices able to produce a similar running wattage, this inverter generator and its lowest emitted noise of 69 dBA is on the noisier side. If you value reduced noise levels, the Westinghouse iGen4500DF could be worth considering. It's one of the quietest generators in its power range, rated at 52 dBA.
- As the WH03662OF features an autonomy of up to 25 hours at 25% load, it has one of the highest run times in comparison to the other inverter generators of its power range.
- While the run time is an important parameter, it is dependent on the fuel tank's capacity and thus, doesn't say much on its own unless we consider fuel consumption as well. Compared to similar devices, this inverter generator is less fuel-efficient than most: it burns around 0.24 gallons of gasoline per hour at a 25% load. If you wish to get a unit of similar power, but with one of the best fuel efficiency, you could consider the Champion 201319, which has an impressively low fuel consumption of 0.16 GPH.
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 expensive side of the price range.
While certainly not the cheapest of its kind, purchasing it would most likely also mean enjoying the reliability of a high-end product.
The bottom line
- Dual Fuel
- CO Alert technology
- Several accessories included
- RV adapter included
- Electric start
- Parallel capable
- Inverter
- High run time
- On the expensive side
- No 240V output
- No remote start
- On the heavy side (119 lbs)
- On the noisy side (69 dBA)
- Low fuel efficiency
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 |
| 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 |
Unlike many websites, we did our best to research each of the specs above. That being said, we are not immune to making the occasional mistake or omission. Should you notice any missing or incorrect values, don't hesitate to suggest improvements so we can address the issue.
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.
