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.
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.
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.
Tell us about the application — kW, voltage, application, install timeline — and we'll respond within one business day with budgetary pricing, lead time, and any sizing notes.
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.
Component
Symptom
Typical hours
Severity
Spark plugs / ignition
Misfire under load, cylinder dropout codes, rough idle
500+
minor
Turbocharger seals
Oil in intake, blue smoke, boost pressure loss
10,000+
moderate
Fuel pressure regulator / vaporizer
Hard starting, gas pressure fault, erratic idle
8,000+
moderate
Battery (starting)
Slow crank, failed exercise
8,760+
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.
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