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Compare Generators Side-by-Side

Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.

  • Firman H03655
  • Sportsman GENMAX1500
  • Model H03655
    Model H03655

    Firman 3,650W Dual-Fuel Generator

    3650W
    Running
    67 dB
    Noise
    View details
  • Model GENMAX1500
    Model GENMAX1500

    Sportsman 900W Gas Generator

    900W
    Running
    65 dB
    Noise
    View details
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
Generator Specifications Comparison
SpecificationFirman H03655Sportsman GENMAX1500
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Gasoline
InverterNoNo
Parallel capableNoNo
RV readyYesNo
Running watts
Winner: Winner: 3650 W
900 W
Starting watts
Winner: Winner: 4550 W
1500 W
Noise (lower limit)
67 dB
Winner: Winner: 65 dB
Weight
112 lbs
Winner: Winner: 45 lbs
Run time @50% load
Winner: Winner: 14 h
8 h
Run time @25% load
Not available—
Not available—
Fuel tank
5 gal
1 gal
Fuel gaugeYesNo
Approx. dimensions (L × W × H)
25.7 x 21.8 x 21.6
16 x 14 x 16
Electrical
Voltage (AC)
120V 60 Hz
120
Voltage (DC)
Not available—
12
GFCI outletsNoNo
Covered outletsYesNo
Automatic Voltage RegulationYesNo
THD
25 %
Not available—
Engine
Engine
208 cc OHV 4-stroke, cast iron sleeve
72 cc 2-stroke
Alternator
Not available—
Not available—
Starting system
Recoil
Recoil
Warranty
Warranty
3 years
1 years
Power by fuel
GasolineNot available—Not available—
Running watts
3650 W
900 W
Starting watts
4550 W
1500 W
Running amps (120V)
Not available—
Not available—
Running amps (240V)
Not available—
Not available—
Peak amps (120V)
Not available—
Not available—
Peak amps (240V)
Not available—
Not available—
Run time @50% load
14 h
8 h
Run time @25% load
Not available—
Not available—
PropaneNot available—Not available—
Running watts
3300 W
Not available—
Starting watts
4100 W
Not available—
Running amps (120V)
Not available—
Not available—
Running amps (240V)
Not available—
Not available—
Peak amps (120V)
Not available—
Not available—
Peak amps (240V)
Not available—
Not available—
Run time @50% load
Not available—
Not available—
Run time @25% load
Not available—
Not available—
Other
Data center
Not available—
Not available—
Indicators
false
false
Compliance
EPA, ANSI/PGMA G300-2023
EPA
Security
Not available—
Not available—
Spark arrestorYesNo
Neutral
Floating
Not available—
UPC
840876136553
27077805444
Core / High-priority specs
Running Watts (Gasoline)
3650
900
Running Watts (Propane)
3300
Not available—
Starting Watts (Gasoline)
4550
1500
Starting Watts (Propane)
4100
Not available—
Runtime @ 50% Load (Gasoline)
14
8
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120V 30A (TT-30R)
1x Duplex 120V 20A (5-20R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
208 cc OHV 4-stroke, cast iron sleeve
2-stroke
Engine Displacement
208
72
Cylinder Sleeve
cast iron sleeve
Not available—
Runtime & fuel system
Runtime @ 50% Load (Gasoline)
14
8
Safety & compliance
Overload Protection System
Low oil and overload protection
Not available—
Low Oil ProtectionYesNo
Carbon Monoxide MonitoringYesNo
Included equipment
Starting Components
Oil, funnel, tool kit, propane hose, and wheel kit
Not available—
Included Accessories
Oil, funnel, tool kit, propane hose, and wheel kit
Tool kit and battery charging cables
Warranty & identification
Residential Warranty
3
Not available—
Commercial Warranty
3
Not available—
Additional specs
Summary
The Firman H03655 is a 3,650-watt dual-fuel generator built around a 208 cc OHV 4-stroke engine with a cast iron sleeve. Running on gasoline, it delivers 4,550 starting watts and 3,650 running watts. Switch to propane and output drops to 4,100 starting watts and 3,300 running watts. This power level runs a refrigerator, microwave, window air conditioner, or multiple power tools simultaneously. The dual-fuel flexibility means you can operate on whichever fuel is available, a practical advantage during extended outages or when propane storage is more convenient than gasoline. At 67 dB at quarter load, the H03655 operates quietly enough for residential neighborhoods without disturbing neighbors. The 5-gallon tank delivers 14 hours of runtime at 50 percent load on gasoline, translating to roughly one full day of moderate use before refueling. The RV-ready configuration and included wheel kit position this unit as a go-anywhere power source for camping, job sites, and home backup scenarios.
The Sportsman GENMAX1500 is a portable 2-cycle gasoline generator offering 1,500 surge watts and 900 running watts, suitable for powering common household appliances and power tools.
  • Most Powerful
    Firman H03655
    3650W running
  • Quietest
    Sportsman GENMAX1500
    65 dB
  • Longest Runtime
    Firman H03655
    14h at 50% load
Where to buy
Prices can change. We update these automatically.
Firman H03655
Store links
No links yet.
Sportsman GENMAX1500
Store links
No links yet.
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