Problems on this page:
Clean steam quality failing tests
Hits OEE: Quality
Symptoms: Condensate samples fail conductivity, endotoxin or non-condensable gas tests.
Feed water quality poor
Check the feed water from the purified water system.
Separator or demister not removing droplets
Check the separator and the steam velocity in the generator.
Non-condensable gases not removed from the feed
Check the degassing of the feed water.
Sample point or cooler contaminated
Clean and sanitise the sample cooler and its line.
Prevention: Clean steam sampled at the points and frequency the quality plan sets.
Pressure not holding at the user points
Hits OEE: Availability
Symptoms: Steam pressure drops when autoclaves or SIP cycles draw steam.
Plant steam supply to the generator low
Check the plant steam pressure and control valve on the heating side.
Generator undersized for simultaneous users
Check whether several users are drawing steam at the same time and schedule them.
Feed water pump not keeping level
Check the feed pump and the level control.
Heat exchanger fouled on the plant steam side
Check the plant steam condensate removal and the exchanger.
Prevention: Clean steam pressure trended with the user cycles.
Wet steam at the user points
Hits OEE: Quality
Symptoms: Users find wet steam, wet loads or condensate in the lines.
Steam traps on the clean steam lines failing closed
Test the traps on the distribution.
Lines not sloped or not insulated
Check the slopes and the insulation of the distribution.
Level in the generator too high
Check the level control so water is not carried over.
Demand surge pulling water over
Check the start-up sequence of the users.
Prevention: Dryness tested at the user points on the schedule the quality plan sets.
Generator tripping on alarms
Hits OEE: Availability
Symptoms: The generator stops on level, pressure or conductivity alarms.
Conductivity sensor dirty or drifting
Clean and calibrate the conductivity sensor.
Level sensor fault
Check the level sensors against the sight glass.
Safety valve or pressure switch fault
Have the safety devices tested by qualified staff; never bypass them on a pressure vessel.
Feed water supply interrupted
Check the purified water loop pressure.
Prevention: Alarm history reviewed weekly.
Scaling or rouging inside
Hits OEE: Availability
Symptoms: Inspection finds scale or rouge, and steam quality or capacity falls.
Feed water hardness or silica too high
Check the pretreatment of the feed water.
Blowdown not done on schedule
Check the blowdown setting and valve.
Rouge from the stainless system
Plan derouging and passivation with a specialist.
Operating temperature higher than design
Check the operating pressure setting.
Prevention: Internal inspection and rouge assessment on the schedule the site sets.
Heating side control unstable
Hits OEE: Performance
Symptoms: Clean steam pressure swings even with steady demand.
Plant steam control valve hunting
Tune the pressure control loop and check the valve for stiction.
Condensate not draining from the heating side
Check the steam trap on the heating side, since flooded tubes lose heating surface.
Pressure transmitter fault
Check the pressure transmitter against a calibrated gauge.
Valve actuator air supply unstable
Check the instrument air pressure and dryness at the valve actuator.
Prevention: Pressure trend reviewed weekly.
Energy use too high
Hits OEE: Performance
Symptoms: The generator uses more plant steam for each kilogram of clean steam than it used to.
Blowdown set more often than needed
Check the blowdown interval against the feed water quality.
Insulation damaged or wet
Repair the insulation on the generator and the distribution.
Traps on the clean steam lines passing live steam
Test the traps and repair those passing steam.
Generator kept at full pressure while no one draws steam
Use a standby pressure during long breaks where the validation allows it.
Prevention: Plant steam use per kilogram of clean steam recorded monthly.
Feed water pump faults
Hits OEE: Availability
Symptoms: The feed water pump trips, leaks or cannot keep the level in the generator.
Mechanical seal leaking
Replace the seal with a type suited to hot purified water.
Cavitation from low suction pressure
Check the purified water loop pressure at the pump suction.
Motor or drive fault
Check the motor and its drive for faults.
Air trapped in the pump after maintenance
Vent the pump before restarting it.
Prevention: Feed pump condition checked weekly.
Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.
Related equipment guides: steam boiler · autoclave · reverse osmosis system · steam trap · distillation column
Stop the same fault coming back
Recurring clean steam generator stops usually trace to a cause you cannot see by hand. The partner we recommend is Fabrico: it tracks OEE and downtime live from PLCs, IoT sensors or AI cameras; where cameras are fitted, the video of a stop sits next to its machine data so the cause can be reviewed; and a technician opens the work order from the stop in the same system. Data is hosted in the AWS EU region, and Fabrico and the company behind it hold ISO/IEC 27001, ISO/IEC 20000-1 and ISO 9001.
Book a Fabrico demo
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Related tools: full troubleshooting directory · OEE calculator · downtime cost · MTBF / MTTR · glossary
Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover