Kohler · REZX Series (Industrial Gaseous)

Kohler 350REZXB

355 kW standby / 305 kW prime · LPG · Liquid-cooled

355 kW LPG industrial standby generator. Enclosed gaseous standby with Doosan engine and pilot-excited permanent-magnet alternator.

Kohler Kohler 350REZXB generator — specifications and details
Standby power
355 kW / 305 kW prime
Voltage options
120/208V, 277/480V
Frequency / Phase
60 Hz · 3-phase
Engine
Doosan D183TIC · 18.273L
Alternator
Kohler Brushless, Permanent-Magnet Pilot Exciter

Overview#

The Kohler 350REZXB is a 355-kilowatt LPG industrial standby generator in an enclosed configuration. Rated at 240-355 kW standby depending on voltage, it uses a Doosan engine paired with a brushless permanent-magnet pilot exciter alternator at 1800 RPM. This unit is EPA certified for both stationary emergency and non-emergency applications, with hurricane-rated enclosure options available.

Gaseous vs diesel at 355 kW#

At 355 kW, gaseous generators eliminate on-site diesel fuel storage requirements and SPCC compliance. LPG provides clean combustion with lower emissions than diesel and avoids fuel degradation issues. At this power level, propane consumption is substantial, requiring careful tank sizing and delivery contract planning for extended outage scenarios. Facilities with reliable propane supply chains benefit from the lower maintenance burden compared to diesel.

Our service experience#

OnPoint Generators provides installation, maintenance, and emergency service for Kohler gaseous generators throughout Northern California. The Doosan engine platform in the larger REZX units is built for the 300+ kW class, and we structure PM programs around annual ignition, fuel system, and coolant inspections with attention to the pilot exciter alternator system.

Engineering specifications

Physical

Length
147.4 in
Width
67.4 in
Height
97 in
Wet weight
9,900 lb

Fuel system & runtime

NG required pressure
7 in WC

Photos

Kohler 350REZXB — product photo

Documents & downloads

Spec sheets & manuals

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Service intervals

Manufacturer-recommended intervals for the Kohler 350REZXB under standby duty. Field intervals may differ based on load profile, ambient conditions, and fuel quality.

Oil & filter
Every 250 hours or 12 months
Coolant change
Every 3000 hours
Air filter
Every 500 hours
Spark plugs
Every 500 hours
Major overhaul
8,000 hours
Load bank test
Every 12 months

Common failure modes

What we've seen fail on this platform. Use as a service-planning reference, not a diagnostic — actual failure modes depend heavily on duty cycle and maintenance history.

ComponentSymptomTypical hoursSeverity
Spark plugs / ignitionMisfire under load, cylinder dropout codes, rough idle500+minor
Turbocharger sealsOil in intake, blue smoke, boost pressure loss10,000+moderate
Fuel pressure regulator / vaporizerHard starting, gas pressure fault, erratic idle8,000+moderate
Battery (starting)Slow crank, failed exercise8,760+minor

Frequently Asked Questions

What is the standby rating of the Kohler 350REZXB?
The 350REZXB is rated 240-355 kW standby (300-444 kVA) depending on voltage configuration, with prime ratings of 275-305 kW, operating on LPG at 60 Hz.
What fuel does the Kohler 350REZXB use?
The 350REZXB operates on LPG (propane). Natural gas and dual-fuel variants are also available in the REZX line.
What is the difference between RZX and REZX models?
RZX designates the open-frame (skid-mounted) configuration, while REZX is the enclosed (sound-attenuated or weather-protective) version. Both use the same engine-alternator package; the difference is the enclosure.

Compatible equipment

More in the REZX Series (Industrial Gaseous)

Kohler REZX enclosed gaseous gensets from 190 to 500 kW — LPG, natural gas, or dual-fuel with Doosan power.

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