Generator entity · Inverter (portable)

Firman WT05571 Tri Fuel Inverter

Tri-fuel inverter with the fullest outlet panel in this index: 5,500 W running / 6,850 W starting on gasoline (5,000 W propane, 4,500 W natural gas running), 120/240 V with TT-30R, L14-30R, AND 14-50R, CO Alert shutdown, PGMA G300-2023 and CSA certified — 59.6 kg.

brand: Firman family: Whisper Series (WT) fuel: Gasoline + Propane (LPG) + Natural gas confidence: medium updated: Jul 8, 2026

Outdoor use only. Fuel-burning generators produce carbon monoxide and must never run indoors, in garages, or near openings — regardless of CO-shutdown features. This unit: automatic co shutdown present (CO Alert). Home-circuit connection requires a proper transfer switch installed by an electrician; never backfeed an outlet. Follow the manufacturer's manual.

Machine summary · generator · firman-wt05571

brand
Firman
model_name
WT05571 (Whisper Series Tri Fuel Inverter)
generator_type
inverter_portable
fuel
gasoline+propane+natural_gas
running_watts
5500
starting_watts
6850
voltage
120/240V
co_shutdown
present
rv_outlet_present
true
weight_kg
59.6
confidence_level
medium
source_last_checked
2026-07-08
json_export
/generators/firman-wt05571.json

Overview

Firman's WT05571 is the rare tri-fuel inverter: gasoline, propane, or natural gas through a digital inverter, with per-fuel running watts published for all three (5,500 / 5,000 / 4,500 W). Its natural-gas STARTING watts conflict between Firman's own sources (page 5,500 vs manual 5,600) and are stored as unresolved. The panel is the most complete here: a manual-designated TT-30R RV receptacle, L14-30R and 14-50R for 240 V work, a GFCI 5-20R duplex, 60 W USB-C, and 12 V DC. CO Alert shuts the engine down on CO buildup (Firman's manual explicitly says it does not replace CO alarms), with PGMA G300-2023 and CSA C22.2 No. 100-14 conformance stated. THD is null: the manual's spec table appears to transpose power factor and THD, so no clean numeric exists. Runtime is 14.5 h at 1/4 load — fuel unlabeled by Firman but implied gasoline (the 5.3 gal onboard tank), flagged accordingly.

Variant note: WT05571F refurbished variant excluded. Firman's T07571 (7,500 W tri-fuel conventional) was REJECTED from this index on the CO-shutdown gate — no CO Alert documented. Related CO Alert models: T07573, WT06073, T06373.

Data note: NG starting-watts conflict (page 5,500 vs manual 5,600) left unresolved: startingWattsByFuel omits natural_gas, both values preserved in provenance. THD null: manual prints 'Power Factor: <3%' and 'THD: 1' — apparently transposed; no clean official numeric exists. The 14.5 h @ 1/4 load runtime lacks an explicit fuel label (implied gasoline onboard tank) — runtimeByFuelAndLoad left null, headline field kept with the caveat. Noise (67 dB @ 1/4 load) lacks a distance basis. Weight (131.4 lb = 59.6 kg) not explicitly labeled dry. Overload behavior per manual: warning above ~5,710 W; receptacle cutoff in 10 s above ~5,950 W, 2 s above ~6,050 W. Two units parallel to 11,000 W total.

Specifications

Running and starting watts are never collapsed; every runtime figure carries its fuel and load basis; THD is shown only when officially stated numerically. Core values' original claims and sources are in the provenance table. The final group is computed from the fields above and marked as derived.

Output
AttributeValue
Running (rated) watts 5,500 W
Starting (peak) watts 6,850 W
Running watts by fuel Gasoline: 5,500 W · Propane (LPG): 5,000 W · Natural gas: 4,500 W
Starting watts by fuel Gasoline: 6,850 W · Propane (LPG): 6,250 W
Voltage 120/240V
Frequency 60Hz
Total harmonic distortion Not numerically stated
240V support Yes
Fuel & runtime
AttributeValue
Fuel Gasoline + Propane (LPG) + Natural gas
Fuel tank (gasoline) 5.3 gal
Runtime — Gasoline, 25% load 14.5 h
Fuel notes NG supply: 7–11 inches water column; consumption 19.8/39.9/78 ft³/h at no/half/full load. LPG consumption 0.8/3/5.3 lb/h. The 14.5 h @ 1/4 load runtime is not fuel-labeled by Firman (implied onboard gasoline tank; LPG/NG run from external supply). Economy Control (Eco Mode) reduces consumption and noise at light loads. Noise distance basis unpublished.
Engine & operation
AttributeValue
Engine displacement 322 cc
Noise 67 dBA (at 1/4 load)
Start method recoil, electric
Parallel capable Yes
Inverter technology Yes
Receptacles
AttributeValue
Receptacles 2 × 5-20R (one duplex, 120V 20A GFCI), 1 × TT-30R (120V 30A RV (not GFCI protected), max 22.9A), 1 × L14-30R (120/240V 30A twist-lock (22.9A / 5,500 W)), 1 × 14-50R (120/240V (22.9A / 5,300 W single unit; 45.8A in parallel operation)), 1 × USB-C (PD 3.1, 60 W), 1 × 12V DC (8.3A / 100 W)
RV outlet (30A RV receptacle) Yes
TT-30R present Yes
L14-30R present Yes
GFCI outlets Yes
Covered outlets Yes
Safety & compliance
AttributeValue
CO shutdown Automatic CO shutdown present (CO Alert)
Low-oil shutdown Yes
Overload protection Yes
EPA certified Yes
CARB compliant Yes
CSA/ETL listing CSA C22.2 No. 100-14
PGMA compliant Yes
Physical
AttributeValue
Weight (dry) 59.6 kg (131.4 lb)
Dimensions (L × W × H) 698.5 × 541 × 574 mm
Wheel kit included Yes
Handle fixed
Type Inverter (portable) · Cart style
Derived (computed, not sourced)
AttributeValue
Watts per kg 92.3 W/kg
Portability band mid

Use cases

  • RV power via the manual-designated TT-30R with 5,500 W of inverter output
  • Home backup with three fuel paths including household natural gas
  • Transfer-switch setups via L14-30R / 14-50R at 240 V
  • Long outages: NG supply removes tank limits entirely

Cross-category fit flags (stored for future battery-vs-generator pages, not yet used for ranking): RV suitable · camping not suitable · home backup suitable · apartment use: no · sensitive electronics: medium · noise class: moderate.

Strengths and weaknesses

Strengths

  • Tri-fuel inverter — the only unit in this index combining both traits
  • TT-30R, L14-30R, AND 14-50R on one panel
  • CO Alert with PGMA G300-2023 and CSA C22.2 No. 100-14 conformance stated
  • CARB and EPA emissions conformance stated in the manual
  • 60 W USB-C and 12 V DC on board; 3-year warranty

Weaknesses

  • Natural-gas starting watts conflict between Firman's own sources (5,500 vs 5,600) — stored unresolved
  • THD unpublishable: the manual's spec table appears to transpose power factor and THD
  • Runtime figure is not fuel-labeled by Firman
  • 14-50R delivers only 22.9 A / 5,300 W from a single unit despite the 50 A receptacle form
  • 59.6 kg — wheeled, not carried

Comparisons featuring this generator

High-Output Dual & Tri-Fuel Home-Backup Generators: DuroMax XP13000EH vs Westinghouse iGen11000TFc vs WGen9500DF vs Champion 201412 vs DuroMax XP9000iH vs Firman WT05571

Six high-output 120/240 V multi-fuel generators for whole-house backup through a transfer switch — 5,500–10,500 W running, dual- and tri-fuel, conventional and inverter. They separate on output, fuel flexibility, power quality (only the inverters offer clean THD), and one critical safety point: five have CO-shutdown, one documents that it does not.

RV-Ready Generators: WEN DF360iX vs Champion 201531 vs Westinghouse iGen5000DFc vs Firman WT05571 vs Honda EU2200i Companion

Five generators with genuine RV receptacle evidence — a TT-30R (or, for the Honda, a Honda-marketed L5-30R) on the panel, not just 'RV Ready' marketing. They span 1,800–5,500 W running, single- to tri-fuel, and 21.5–59.6 kg, all with documented CO-shutdown.

Where to buy

Merchant links are scaffolded but not yet active. When live, some will be affiliate links; merchant relationships never affect indexed specifications or verdicts.

Sources and provenance

Core specifications — including all safety fields — come from official manufacturer sources only, with the exact claim text preserved per field. Safety-related fields carry the strictest rules: CO-shutdown status is never inferred from marketing. See the methodology for the full policy.

Field-level provenance (19 entries, checked 2026-07-08)
FieldNormalized valueRaw claimSourceConfidence
runningWatts 5500 Running watts 5500W (GAS), 5000W (LPG), 4500W(NG) Official product page — Manual spec table agrees: 'Running Watts* 5500(GASOLINE)/5000(LPG)/4500(NG)'. high
startingWatts 6850 Starting watts 6850W (GAS), 6250W (LPG), 5500(NG) Official product page — Gasoline figure; manual agrees on GAS/LPG. high
runningWattsByFuel {"gasoline":5500,"propane":5000,"natural_gas":4500} Running Watts* 5500(GASOLINE)/5000(LPG)/4500(NG) Official manual (PDF) — All three fuels numerically published; page identical. high
startingWattsByFuel {"gasoline":6850,"propane":6250} Starting Watts 6850(GASOLINE)/6250(LPG)/5600(NG) Official manual (PDF) — CONFLICT on NG: manual 5,600 vs page 5,500 — NG omitted from the normalized map, both values preserved here per the conflict rule. medium
voltage 120/240V Rated AC Voltage 120/240V Official manual (PDF) — Page: '120/240 AC Volts'. high
receptacleSummary {"5-20R":2,"TT-30R":1,"L14-30R":1,"14-50R":1,"USB-C":1,"12V DC":1} (1) 5-20R 120V 20A DUPLEX GFCI / (1) TT-30R 120V 30A TWISTLOCK / (1) L14-30R 120V/240V 30A TWISTLOCK (22.9A/240V/5500W) / (1) 14-50R 120V/240V 50A (22.9A/240V/5300W) / (1) USB-C (3.1/5A/5/9/12/15/20V DC/60W) / (1) 12V DC Power Port/Plug (8.3A/12V DC/100W) Official product page — Manual confirms each receptacle by NEMA code; 14-50R limited to 22.9A single-unit (45.8A in parallel). high
rvOutletPresent true 9. 120V, 30A RV – NEMA TT-30R (not GFCI protected) Official manual (PDF) — Manufacturer explicitly designates the TT-30R as the RV receptacle. high
fuelTankCapacityGal 5.3 Capacity Fuel Tank 5.3 U.S. Gallons (20L) Official manual (PDF) high
runtimeAt25LoadHours 14.5 Up to 14.5 hours of run time at 1/4 load Official product page — Load basis explicit; fuel NOT labeled by Firman (implied onboard gasoline tank, since LPG/NG use external supply) — runtimeByFuelAndLoad left null per policy. medium
noiseDb {"quarter_load":67} 67dB ¼ load Official product page — Load basis stated; measurement distance not stated anywhere official. medium
totalHarmonicDistortion Power Factor: <3% ... Total Harmonic Distortion(THD): 1 Official manual (PDF) — Values appear transposed in the manual spec table (power factor 1 and THD <3% would be expected); no clean official numeric — null per policy, suitability capped at medium. low
coShutdown present CO Alert automatically shuts down the engine when harmful levels of carbon monoxide accumulate around the generator or a CO Alert fault occurs. Official manual (PDF) — Manual section 'CO Alert(TM) Carbon Monoxide (CO) Shutdown System'; also warns 'CO Alert DOES NOT replace carbon monoxide alarms.' high
weightKg 59.6 Weight: 131.4 lbs Official product page — 131.4 lb × 0.453592 = 59.6 kg; not explicitly labeled dry. medium
dimensionsMm {"l":698.5,"w":541,"h":574} measures 22.6"H x 21.3"D x 27.5"W, weighs 131.4 lbs. Official product page — Converted ×25.4, mapped l=27.5"W, w=21.3"D, h=22.6"H from the page's H×D×W ordering. medium
engineSizeCc 322 322cc FIRMAN engine Official product page high
warrantyYears 3 FIRMAN Three (3) Year Limited Warranty Official manual (PDF) — Separate 2-year federal/California emissions warranty also in manual. high
pgmaCompliant true complies with PGMA (Portable Generator Manufacturers' Association) standard ANSI/PGMA G300-2023, Safety and Performance of Portable Generators. Official manual (PDF) — Same footnote cites CSA C22.2 No. 100-14 certification. high
carbCompliant true Designed, built, and equipped so as to conform with all applicable regulations adopted by the Air Resources Board and US EPA Official manual (PDF) — From the manual's California/Federal emissions control warranty statement. medium
parallelCapable true two WT05571 units can be paralleled to 11000 W total Official manual (PDF) — FIRMAN parallel kit required; 14-50R reaches 45.8A in parallel operation. high

All sources used

entity: generator/firman-wt05571 source_last_checked: 2026-07-08 confidence_level: medium methodology: /methodology/