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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 T04073
  • Genmax GM2200i
  • Model T04073
    Model T04073

    Firman 4,000W Tri-Fuel Generator

    4000W
    Running
    67 dB
    Noise
    View details
  • Model GM2200i
    Model GM2200i

    Genmax 1,800W Gas Generator

    1800W
    Running
    58 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 T04073Genmax GM2200i
General
Product type
Generator
Generator
Fuel
Tri-Fuel
Gasoline
InverterNoYes
Parallel capableNoYes
RV readyNoNo
Running watts
Winner: Winner: 4000 W
1800 W
Starting watts
Winner: Winner: 5000 W
2200 W
Noise (lower limit)
67 dB
Winner: Winner: 58 dB
Weight
123.4 lbs
Winner: Winner: 41.9 lbs
Run time @50% load
Winner: Winner: 12 h
6 h
Run time @25% load
14 h
8 h
Fuel tank
5 gal
1 gal
Fuel gaugeYesNo
Approx. dimensions (L × W × H)
29.8 x 27.5 x 26.1
18.9 x 11.4 x 17.3
Electrical
Voltage (AC)
120/240
120
Voltage (DC)
Not available—
5
GFCI outletsYesNo
Covered outletsYesYes
Automatic Voltage RegulationYesYes
THD
11%-14% %
<3% %
Engine
Engine
223 cc OHV 4-stroke, cast iron sleeve
79.7 cc Dinking OHV 4-stroke
Alternator
Not available—
Not available—
Starting system
Recoil, Electric
Recoil
Warranty
Warranty
3 years
1 years
Power by fuel
GasolineNot available—Not available—
Running watts
4000 W
1800 W
Starting watts
5000 W
2200 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
6 h
Run time @25% load
Not available—
8 h
Natural gasNot available—Not available—
Running watts
3200 W
Not available—
Starting watts
4000 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—
PropaneNot available—Not available—
Running watts
3600 W
Not available—
Starting watts
4500 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
9 h
Not available—
Run time @25% load
Not available—
Not available—
Other
Data center
Not available—
Not available—
Indicators
true
true
Compliance
CARB, EPA, ANSI/PGMA G300-2023
EPA, ANSI/PGMA G300-2023
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
true
Not available—
UPC
840876140734
738349925141
Core / High-priority specs
Running Watts (Gasoline)
4000
1800
Running Watts (Propane)
3600
Not available—
Running Watts (Natural Gas)
3200
Not available—
Starting Watts (Gasoline)
5000
2200
Starting Watts (Propane)
4500
Not available—
Starting Watts (Natural Gas)
4000
Not available—
Runtime @ 50% Load (Gasoline)
14
6
Runtime @ 50% Load (Propane)
9
Not available—
Runtime @ 25% Load (Gasoline)
Not available—
8
AC Outlet Types
1x Duplex 120V 20A (5-20R) GFCI; 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R)
1x Duplex 120V 20A (5-20R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
223 cc OHV 4-stroke
Dinking OHV 4-stroke
Engine Displacement
223
79.7
Cylinder Sleeve
cast iron
Not available—
Engine Oil Type
Not available—
10W-30
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
Not available—
8
Runtime @ 50% Load (Gasoline)
14
6
Runtime @ 50% Load (Propane)
9
Not available—
Safety & compliance
Overload Protection System
Low oil and overload protection, CO monitoring
Low oil and overload protection, CO monitoring
Low Oil ProtectionYesYes
Carbon Monoxide MonitoringYesYes
Included equipment
Starting Components
Recoil, Electric
Not available—
Included Accessories
Oil, funnel, tool kit, propane hose, RV adapter, cover, battery, and wheel kit
Funnel and tool kit
Warranty & identification
Commercial Warranty
3
Not available—
Additional specs
Summary
The Firman T04073 is a 4,000-watt tri-fuel generator that runs on gasoline, propane, or natural gas. On gasoline, it delivers 5,000 starting watts and 4,000 running watts, enough to power a refrigerator, microwave, and multiple household circuits simultaneously. On propane, output drops to 3,600 running watts, and on natural gas it falls to 3,200 running watts. This fuel flexibility means users can switch between sources based on availability and cost, a significant advantage during extended outages or in remote locations where one fuel type may be scarce. The T04073 targets homeowners, RV owners, and job site operators who need reliable backup power without the commitment to a single fuel source. Its 5-gallon tank runs for 14 hours at 25% load on gasoline, translating to roughly one week of emergency backup if you run it a few hours per day. The unit includes a wheel kit, making it easier to position despite its 123.4-pound weight.
The GENMAX GM2200i is a 2200-watt gasoline inverter generator featuring a 79.7cc engine, CO detection, and parallel capability, designed for quiet and efficient power supply.
  • Most Powerful
    Firman T04073
    4000W running
  • Quietest
    Genmax GM2200i
    58 dB
  • Longest Runtime
    Firman T04073
    12h at 50% load
Where to buy
Prices can change. We update these automatically.
Firman T04073
Store links
No links yet.
Genmax GM2200i
Store links
No links yet.
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