The Firman W03661OF is a portable open frame 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 W03661OF
In summary, the Firman W03661OF is a portable inverter generator especially useful 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 sure of their ability to power their fridges, cooking tools, heating and lighting equipment during power failures
- Tailgating and campground aficionados with the desire of enjoying power anywhere they go
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 W03661OF
Running on gasoline, the Firman W03661OF operates with a 208 cc OHV 4-stroke engine, delivering 120V, with a running wattage of 3,650W and a peak wattage of 4,500W. Additionally, as the generator is parallel capable (parallel kit not included), it can be linked to a second unit for more power.
At a noise rating of 69 dBA (less noisy than background music), the inverter generator is started via a classic hand-operated recoil starting mechanism.
With its 6 gallons fuel tank, the W03661OF can operate for up to 25 hours when fully fueled (with fuel usage averaging around 0.24 GPH).
With a <3% Total Harmonic Distortion (THD), the W03661OF delivers a clean sine wave—essential for safeguarding your delicate electronics when plugged into its AC outlets.
Outlets
The control panel features 4 AC outlets as follows:
Additionally, it offers 3 DC outlets: there's two 5V USB ports (USB-A) designed for hassle-free charging of various electronic devices such as smartphones and tablets, ensuring uninterrupted usage and a 12V 8A (cigarette lighter style) receptacle providing easy battery charging capabilities.
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
Measuring L24.5 x W24.1 x H23 in, the classic open frame build of the Firman W03661OF delivers stability and easy maintenance access to components, facilitating air circulation. The design is ideal for rough environments and demanding outdoor use.
Despite its weight of 106 lbs, the generator is considered 'portable,' signifying its capability to be moved, albeit its heaviness may hinder easy transport. Nevertheless, it can still be moved quite conveniently with the help of its set of wheels (⌀9") and its folding handle, once it is placed on the ground.
Features
The W03661OF's control panel
The control panel of the W03661OF includes a convenient meter, showing voltage, frequency, and lifetime hours metrics, helpful for the monitoring of its status and activity.
In addition to this info, the device’s light indicators will display if the generator is ready, the generator is on overload and the oil level is too low.
The inverter generator allows for a quick, easy and convenient assessment of its gas level, as it is equipped with a built-in fuel gauge.
As for its security measures, the device features an automatic low oil shut-off and an overload protection (circuit breaker), letting you use it with a peace of mind.
The W03661OF 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 W03661OF also is packed along with the following accessories: tool kit, battery charging cables, oil, RV adapter and funnel.
The Firman W03661OF versus other generators
The following charts are provided to give you an idea of how some of the key specs of the Firman W03661OF compare to inverter generators of similar power (between 3500 and 4500 W).
- At a weight of 106 pounds, the Firman W03661OF places in the expected weight range of the inverter generators in the 3500-4500 rated wattage range. In terms of weight, one of the champions in their power range is the Genmax GM4600iAEFIC, standing at just 58.4 lbs.
- When compared to other units producing a similar running wattage, this inverter generator and its lowest emitted noise of 69 dBA stand out for being on the louder side. If noise emissions are important to you, one of the least noisy generators of this power range is the Westinghouse iGen4500DF with only 52 dBA.
- Compared to inverters of similar power, the W03661OF stands out with one of the highest run times, lasting up to 25 hours at 25% load.
- Run time is a key metric, but it's dependent on the generator's fuel tank capacity. Therefore, discussing fuel efficiency is necessary for a complete understanding. 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. To prioritize fuel savings, we advise considering the Champion 201319, which stands out for its gasoline efficiency, consuming just 0.16 gallons per hour.
Price comparison
As you can see from these interactive charts, when compared to other 3500-4500W inverter generators, the Firman W03661OF 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
- CO Alert technology
- Several accessories included
- RV adapter included
- Parallel capable
- Inverter
- High run time
- Decent weight (106 lbs)
- No 240V output
- No electric start
- On the noisy side (69 dBA)
- Low fuel efficiency
Features and Specifications
| Inverter | Yes |
|---|---|
| Parallel capable | Yes, cable not included |
| RV ready | No |
| Fuel | Gasoline |
| Engine | 208 cc OHV 4-stroke |
| Starting system | Recoil |
| Warranty | 3 years |
| Voltage | AC: 120V 60 Hz, DC: 12V |
|---|---|
| Running watts | 3,650 W |
| Starting watts | 4,500 W |
| Running amps | 30.4 amps |
| Peak amps | 37.5 amps |
| Run time @50% load | Unknown |
| Run time @25% load | 25 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 | 106 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 |
| Security | Low oil and overload protection, CO monitoring |
| Spark arrestor | Yes |
| Neutral | Floating |
| Accessories included | Oil, funnel, tool kit, RV adapter, battery charging cables, and wheel kit |
| Country of origin | China |
| Series | Whisper |
| UPC | 840876136614 |
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 W03661OF 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 | AC (10,000 BTU) | 1500 | 2200 |
| Refrigerator (energy star) | 192 | 1192 | |
| Vacuum cleaner | 1075 | 1175 | |
| Laptop | 150 | 150 | |
| Total | 2917 W | 3917 W | |
| For camping | RV AC (11,000 BTU) | 1010 | 1600 |
| RV refrigerator | 180 | 600 | |
| Electric grill | 1650 | 1650 | |
| Set of 5 LED light bulbs | 55 | 55 | |
| Cell phone charger | 20 | 20 | |
| Total | 2915 W | 3505 W | |
| For work | Grinder | 1400 | 2500 |
| Demolition hammer | 1260 | 1260 | |
| Drain cleaner | 250 | 250 | |
| Total | 2910 W | 4010 W |
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