A Firman 4250 portable generator shown at a three-quarter angle on a white background. The generator features a blue front panel with yellow Firman branding, a black and blue rugged housing, and a detailed yellow and black control panel on the side.
A black and blue FIRMAN portable generator shown on a bright yellow background with white feature callouts and text describing its 1.5 gallon tank, power outlets, electric start, safety features, and economy modes.
An informational product graphic for a control panel showing a labeled black and yellow electrical panel with numbered callouts and text listing components such as engine start switch, CO alert indicator light, economy control switch, LPG/NG hose connect inlet, parallel operation outlets, USB-A and USB-C output port, and 12V DC port. The background is bright yellow with a black header reading CONTROL PANEL.
A blue and black portable generator or power unit shown on a dark textured background with the word INCLUDED at the top and six yellow accessory callouts around it: tool kit, engine oil & oil funnel, battery, battery charger cable, regulator hose assembly, and adapter.
Promotional graphic for a portable generator with the headline 'WHAT WILL YOUR GENERATOR POWER?' in black text on a yellow banner. The generator is shown in black and blue with yellow branding, and white line icons above and below indicate power for portable AC, power tools, RV/camping, appliances, a smart phone, and a laptop.
A portable generator shown from the back on a bright yellow background with promotional text about a 4-year warranty. The generator is black with blue side panels, and the graphic includes a black shield icon with '4 YEAR WARRANTY' and additional support copy.
Close-up of a generator control panel with a CO Alert indicator light and explanatory text on a black background with a yellow header.
A portable generator shown on a bright yellow background with measurement lines and text indicating dimensions: 18.2 inches tall, 12.
An informational graphic with the headline 'WHAT SIZE GENERATOR DO YOU NEED?' in white text on a yellow background. Below, a large blue and black generator is shown with four numbered steps in white and yellow text explaining how to calculate generator size based on running watts and starting watts.
A Firman 4250 portable generator shown at a three-quarter angle on a white background. The generator features a blue front panel with yellow Firman branding, a black and blue rugged housing, and a detailed yellow and black control panel on the side.
A black and blue FIRMAN portable generator shown on a bright yellow background with white feature callouts and text describing its 1.5 gallon tank, power outlets, electric start, safety features, and economy modes.
An informational product graphic for a control panel showing a labeled black and yellow electrical panel with numbered callouts and text listing components such as engine start switch, CO alert indicator light, economy control switch, LPG/NG hose connect inlet, parallel operation outlets, USB-A and USB-C output port, and 12V DC port. The background is bright yellow with a black header reading CONTROL PANEL.
A blue and black portable generator or power unit shown on a dark textured background with the word INCLUDED at the top and six yellow accessory callouts around it: tool kit, engine oil & oil funnel, battery, battery charger cable, regulator hose assembly, and adapter.
Promotional graphic for a portable generator with the headline 'WHAT WILL YOUR GENERATOR POWER?' in black text on a yellow banner. The generator is shown in black and blue with yellow branding, and white line icons above and below indicate power for portable AC, power tools, RV/camping, appliances, a smart phone, and a laptop.
A portable generator shown from the back on a bright yellow background with promotional text about a 4-year warranty. The generator is black with blue side panels, and the graphic includes a black shield icon with '4 YEAR WARRANTY' and additional support copy.
Close-up of a generator control panel with a CO Alert indicator light and explanatory text on a black background with a yellow header.
A portable generator shown on a bright yellow background with measurement lines and text indicating dimensions: 18.2 inches tall, 12.
An informational graphic with the headline 'WHAT SIZE GENERATOR DO YOU NEED?' in white text on a yellow background. Below, a large blue and black generator is shown with four numbered steps in white and yellow text explaining how to calculate generator size based on running watts and starting watts.
01/01
Certification: Certification cETL Certification EPA
Model: wt03473

Tri Fuel Inverter Portable Generator 4250/3400 Watt
Electric Start 120V CO Alert
$1,119.99 USD
Free Shipping on all Generators
SERIES Whisper
TYPE Inverter

The FIRMAN WT03473 Tri-Fuel Portable Inverter Generator delivers clean, reliable power with the flexibility to run on gasoline, propane (LPG), or natural gas (NG). Producing up to 4,250 starting watts and 3,400 running watts on gasoline, this compact inverter generator is a versatile choice for RV travel, camping, tailgating, and portable power needs. Clean inverter power helps support both demanding appliances and sensitive electronics with dependable performance.

Weighing just 52 lbs., the WT03473 is designed for easy transport, storage, and power on the go. Its 1.6-gallon gasoline tank provides up to 8 hours of runtime at 50% load, giving you extended operation without the bulk of a larger generator.

For greater power flexibility, the WT03473 is parallel-capable, allowing you to connect a second compatible unit when additional output is needed. An included L5-30P to TT-30R adapter also makes this portable inverter generator RV-ready without requiring an additional adapter purchase.

FIRMAN CO Alert technology adds an extra layer of safety by continuously monitoring carbon monoxide levels and automatically shutting the generator down if unsafe levels are detected. Compact, lightweight, and fuel-flexible, the WT03473 combines tri-fuel capability, clean inverter power, and RV-ready convenience for adventures, backup power, and everything in between.

The WT03473 comes with an LPG/NG Regulator Assembly, a Battery Charger Cable, an Adaptor L5-30P to TT-30R, Engine Oil, an Oil Funnel, and a Tool Kit

**This product is not certified to ship to California.

LEGENDARY FIRMAN ENGINEERING

  • 145cc FIRMAN Engine
  • Starting Watts: 4250(Gas), 3750(LPG), 3300(NG)
  • Running Watts: 3400 (Gas), 3000(LPG), 2650(NG) 
  • 120 volts
  • Electric Start
  • Recoil Start
  • Low oil shut-off

PERFORMANCE IN A LEAGUE OF ITS OWN

  • 1.5-gallon tank
  • Up to 8 hours of run time at 25% load
  • Weight: 52 lbs
  • 64dB ¼ load 

FEATURES YOU EXPECT FROM FIRMAN

4-year warranty 

New CO alert technology

Multi-featured control panel with covered outlets

Turbo Mode

Super Eco Mode


  • (1) 5-20R 120V 20A
  • (1) L5-30R 120V 30A TWISTLOCK
  • (1) DC Power Port/Plug 8.3A/12V
  • (1) USB-A 5V 3A 9V 3A 12V 2.5A
  • (1) USB-C 5V 3A 9V 3A 12V 2.5A
ENGINEERED IN THE USA

FIRMAN generators are made to endure every condition from cold winter nights to hot summer days to everything in between.

Industry-Leading Warranty

New FIRMAN generators are backed by a 3-year warranty. Refurbished generators have a limited 90 day warranty

Customer Support

Our skilled technicians located in Peoria, AZ are available 7 days a week to provide the support you need when you need it most. 

4250/3400

Gasoline

3750/3000

Liquid Propane

3300/2650

Natural Gas

1.5 Gallon Gas Tank

Up to 8 Hours Run Time

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Manuals

WT03473 Manual English

download

WT03473 Manual Spanish

download

WT03473 Manual French

download

WT03571 Quick Start Guide English

download

WT03473 Quick Start Guide Spanish

download

WT03473 Quick Start Guide French

download

Watch

CO ALERT OVERVIEW

@FIRMANpowerequipment
Image of a Woman holding a handle to an Inverter Generator and walking towards a pick up truck and trailer cart.
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A man shows off his FIRMAN Accessories and Inverter Generator collection.
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A FIRMAN generator is sitting on the bed of a white pick up truck. The truck is parked against a concrete wall.
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