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Firman H05751 vs Sportsman GEN7500DF

Firman H05751 vs Sportsman GEN7500DF

Compare two dual-fuel 7,500W-class generators: Firman runs quieter with longer runtime and 3-year warranty, Sportsman offers slightly more power.

  • Firman H05751
  • Sportsman GEN7500DF

Comparison Overview

The biggest real-world difference is comfort and support: the Firman H05751 is rated at 74 dB with a 3-year warranty, while the Sportsman GEN7500DF is louder at 80 dB and comes with a 1-year warranty. If you expect longer outages or frequent use, those two factors can matter as much as raw wattage.

On power, they are close. The Firman delivers 5700 running watts and 7125 starting watts, and the Sportsman bumps that to 6000 running watts and 7500 starting watts. That extra headroom can help with higher-starting loads like a well pump or larger air compressor, but it is not a night-and-day jump.

Both are dual-fuel, non-inverter open-frame style units, so expect traditional generator sound and power quality that is better suited to tools and basic home circuits than sensitive electronics. Weight is essentially the same (about 194 lb), so plan on wheels and a fairly permanent storage spot.

If you value quieter operation, longer run time at 50% load, and longer warranty coverage, the Firman is the easier fit, while the Sportsman makes sense if you want the slightly higher wattage and can live with more noise and shorter runtime.

Key takeaways

  • Firman H05751 runs at 74 dB and includes a 3-year warranty.
  • Sportsman GEN7500DF delivers 6000 running watts and 7500 starting watts.
  • Firman H05751 provides 12 hours runtime at 50% load (manufacturer rating).
  • Sportsman GEN7500DF provides 9 hours runtime at 50% load (manufacturer rating).
  • Both are dual-fuel, non-inverter open-frame generators weighing about 194 lb.

Best use cases

Choose the Firman H05751 if you want a more livable generator for home backup and longer runs. Its 74 dB rating is still not “quiet,” but it is noticeably easier to tolerate than an 80 dB unit when it is running for hours. At 12 hours at 50% load, it is also better suited to overnight use or stretching fuel during an outage. The 3-year warranty is a practical advantage if you expect to use it season after season. This is a good match for powering essentials through a transfer switch (fridge, lights, furnace fan) and for job site tools where you want solid output without pushing the generator hard all day.

Choose the Sportsman GEN7500DF if your priority is squeezing out a bit more capacity for demanding starts. With 6000 running watts and 7500 starting watts, it gives you a little more cushion for loads that surge, like a well pump, sump pump, or a larger compressor, especially if you are trying to run multiple circuits at once. The tradeoffs are real: it is rated at 80 dB, which can feel harsh in a neighborhood or near a campsite, and its 9 hours at 50% load means more frequent refueling during longer outages. The 1-year warranty also makes it a better fit for occasional, need-it-when-it-counts use rather than heavy, frequent operation.

For RVs and camping, neither is ideal since both are non-inverter and heavy, but if you must choose, the Firman’s lower noise is typically easier to live with.

Verdict & recommendation

If your priority is a generator that is easier to live with during longer outages, the Firman H05751 is the more balanced pick thanks to 74 dB noise, 12 hours at 50% load, and a 3-year warranty. If your priority is maximizing starting and running capacity in this size class, the Sportsman GEN7500DF’s 7500 starting watts and 6000 running watts can be worth it for tougher motor starts.

Both are heavy, open-frame, non-inverter dual-fuel generators, so the decision mostly comes down to whether you value quieter, longer-running ownership (Firman) or a small bump in power (Sportsman). Pick the one that best matches your typical loads and how long you expect it to run at a time.

Last updated March 1, 2026

  • Model H05751
    Model H05751

    Firman 5,700W Dual-Fuel Generator

    5700W
    Running
    74 dB
    Noise
    View details
  • Model GEN7500DF
    Model GEN7500DF

    Sportsman 6,000W Dual-Fuel Generator

    6000W
    Running
    80 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 H05751Sportsman GEN7500DF
General
Product type
Generator
Generator
Fuel
Dual-Fuel
Dual-Fuel
InverterNoNo
Parallel capableNoNo
RV readyNoYes
Running watts
5700 W
Winner: Winner: 6000 W
Starting watts
7125 W
Winner: Winner: 7500 W
Noise (lower limit)
Winner: Winner: 74 dB
80 dB
Weight
194.5 lbs
Winner: Winner: 194 lbs
Run time @50% load
Winner: Winner: 12 h
9 h
Run time @25% load
Not available
Not available
Fuel tank
8 gal
6.2 gal
Fuel gaugeYesYes
Approx. dimensions (L × W × H)
30.2 x 27.5 x 26.3
30.8 x 26.5 x 27
Electrical
Voltage (AC)
120/240V 60 Hz
120/240V 60 Hz
Voltage (DC)
Not available
12V
GFCI outletsYesYes
Covered outletsYesNo
Automatic Voltage RegulationYesYes
THD
25 %
Not available
Engine
Engine
Firman Max-Pro Series OHV 4-stroke, cast iron sleeve
389 cc OHV 4-stroke
Alternator
Not available
Not available
Starting system
Recoil, Electric
Recoil, Electric
Warranty
Warranty
3 years
1 years
Power by fuel
GasolineNot availableNot available
Running watts
5700 W
6000 W
Starting watts
7125 W
7500 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
12 h
9 h
Run time @25% load
Not available
Not available
PropaneNot availableNot available
Running watts
Not available
5400 W
Starting watts
Not available
6700 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
Not available
5 h
Run time @25% load
Not available
Not available
Other
Data center
Not available
Not available
Indicators
false
false
Compliance
CARB, EPA
EPA
Security
Not available
Not available
Spark arrestorYesNo
Neutral
true
Not available
UPC
840876157510
27077078343
Core / High-priority specs
Running Watts (Gasoline)
5700
6000
Running Watts (Propane)
Not available
5400
Starting Watts (Gasoline)
7125
7500
Starting Watts (Propane)
Not available
6700
Runtime @ 50% Load (Gasoline)
12
9
Runtime @ 50% Load (Propane)
Not available
5
AC Outlet Types
2x Duplex 120V 20A (5-20R) GFCI; 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R)
2x Duplex 120V 20A (5-20R) GFCI1x 120V 30A (TT-30R)1x 120/240V 30A (L14-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
Max-Pro Series OHV 4-stroke
OHV 4-stroke
Engine Displacement
439
389
Cylinder Sleeve
cast iron sleeve
Not available
Engine Oil Type
Not available
SAE10W-30
Runtime & fuel system
Runtime @ 50% Load (Gasoline)
12
9
Runtime @ 50% Load (Propane)
Not available
5
Safety & compliance
Overload Protection System
Low oil and overload protection
Low oil and overload protection
Low Oil ProtectionYesYes
Included equipment
Included Accessories
Oil, funnel, tool kit, propane hose, battery, and wheel kit
Tool kit, propane hose, battery charging cables, and wheel kit.
Warranty & identification
Commercial Warranty
3
Not available
Additional specs
Summary
The Firman H05751 is a 5,700-watt dual-fuel generator that bridges residential backup and jobsite work. At this wattage, you can run a refrigerator, sump pump, and several household circuits simultaneously, or power mid-range tools like circular saws and air compressors, but not both at once. The dual-fuel design lets you switch between gasoline and propane depending on fuel availability, which matters during emergencies when one source may be scarce. At 194.5 pounds with an included wheel kit, this is a stationary or two-person portable unit. The 8-gallon tank delivers 12 hours at 50% load, meaning one full day of moderate use before refueling.
The Sportsman GEN7500DF is a dual-fuel generator capable of delivering 7,500 surge watts and 6,000 running watts, suitable for powering RVs, household appliances, and power tools.
  • Most Powerful
    Sportsman GEN7500DF
    6000W running
  • Quietest
    Firman H05751
    74 dB
  • Longest Runtime
    Firman H05751
    12h at 50% load
Where to buy
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Firman H05751
Store links
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Sportsman GEN7500DF
Store links
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