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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
  • Ford FG28KVTWTCO
  • Model H03655
    Model H03655

    Firman 3,650W Dual-Fuel Generator

    3650W
    Running
    67 dB
    Noise
    View details
  • Model FG28KVTWTCO
    Model FG28KVTWTCO

    Ford 20,000W Tri-Fuel Generator

    20000W
    Running
    99.7 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 H03655Ford FG28KVTWTCO
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Tri-Fuel
InverterNoNo
Parallel capableNoNo
RV readyYesYes
Running watts
3650 W
Winner: Winner: 20000 W
Starting watts
4550 W
Winner: Winner: 28000 W
Noise (lower limit)
Winner: Winner: 67 dB
99.7 dB
Weight
Winner: Winner: 112 lbs
557 lbs
Run time @50% load
Winner: Winner: 14 h
10.8 h
Run time @25% load
Not available—
Not available—
Fuel tank
5 gal
17.17 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
25.7 x 21.8 x 21.6
39.7 x 27.5 x 45.2
Electrical
Voltage (AC)
120V 60 Hz
120/240V 60 Hz
Voltage (DC)
Not available—
Not available—
GFCI outletsNoYes
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
25 %
Not available—
Engine
Engine
208 cc OHV 4-stroke, cast iron sleeve
999 cc OHV V-Twin
Alternator
Not available—
Not available—
Starting system
Recoil
Electric, Remote
Warranty
Warranty
3 years
3 years
Power by fuel
GasolineNot available—Not available—
Running watts
3650 W
20000 W
Starting watts
4550 W
28000 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
10.8 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, ANSI/PGMA G300-2023
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
Floating
true
UPC
840876136553
814726029418
Core / High-priority specs
Running Watts (Gasoline)
3650
20000
Running Watts (Propane)
3300
Not available—
Starting Watts (Gasoline)
4550
28000
Starting Watts (Propane)
4100
Not available—
Runtime @ 50% Load (Gasoline)
14
10.8
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120V 30A (TT-30R)
2x Duplex 120V 20A GFCI; 1x 120V 30A (L5-30R); 2x 120/240V 30A (L14-30R); 2x 120/240V 50A (14-50R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
208 cc OHV 4-stroke, cast iron sleeve
OHV V-Twin
Engine Displacement
208
999
Cylinder Sleeve
cast iron sleeve
Not available—
Engine Oil Type
Not available—
SAE 10W-30
Runtime & fuel system
Runtime @ 50% Load (Gasoline)
14
10.8
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection
Low Oil ProtectionYesNo
Carbon Monoxide MonitoringYesYes
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
Oil, funnel, tool kit, key fob, natural gas hose with NPT adapter, propane hose, battery, and wheel kit
Warranty & identification
Residential Warranty
3
Not available—
Commercial Warranty
3
3
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 Ford FG28KVTWTCO is a 20,000-watt tri-fuel generator built for whole-home backup, commercial job sites, and stationary power delivery. It runs on gasoline, propane, or natural gas, eliminating single-source fuel dependency. At 557 pounds with a 39.7 x 27.5 x 45.2 inch footprint, this is a semi-permanent installation that demands dedicated storage and logistical planning.
  • Most Powerful
    Ford FG28KVTWTCO
    20000W running
  • Quietest
    Firman H03655
    67 dB
  • Longest Runtime
    Firman H03655
    14h at 50% load
Where to buy
Prices can change. We update these automatically.
Firman H03655
Store links
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Ford FG28KVTWTCO
Store links
No links yet.
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