Deaerator Troubleshooting
Symptom
High O²
Possible Causes
- Air in-leakage
- Insufficient stabilization period
- Trays not installed properly and in place
- Not steady state conditions
- O2 inlet not in accordance with specified designed conditions
- Spray valves not installed correctly
- Water inlet temperature too low
- Improper venting
- Incorrect testing
- Operation outside of design conditions
Comments or Possible Solutions
- Loose fittings
- Shut scavenger off
- Remove chemical interferences
- Verify design conditions
Symptom
Excessive Pressure Fluctuation
Possible Causes
- Steam PRV improperly sized or calibrated
- Improperly sized downcomer and equalizer
- Inlet steam pressure too high or too low
- Excessive inlet temperature variation
- Heater flooding
Comments or Possible Solutions
- Check size and calibration
- Keep within design range
- Check all valve and control settings
Symptom
Low Outlet Temperature
Possible Causes
- Incorrect Thermometer reading
- Insufficient steam flow
- Incorrect steam/water ratio
- Spray valves or internals malfunctioning
- Heater flooding
- Inlet flow piped incorrectly
Comments or Possible Solutions
- Check calibration
- Check steam supply
- Check for restrictions
- Check Pipe and valve sizing
- Check heat and mass balances
- Check spray valves, trays, etc.
- Check all valve and control settings
- Check all inlet flows and temperatures
Symptom
Water Hammer
Possible Causes
- Inlet flows mixing just prior to Deaerator inlet
- Improper pipe design
- High inlet velocities
Comments or Possible Solutions
- Mix flows farther upstream of Deaerator
- Check and/or redesign
- Keep within HEI
Symptom
High CO2
Possible Causes
- High CO2 at inlet
- High pH
- Improper venting
Comments or Possible Solutions
- Verify CO2 design condition
- Lower pH
- Review vent system
Symptom
Tray Upsets
Possible Causes
- Tray hold down not secure
- Turbine trip
- Flashing
Comments or Possible Solutions
- Install correctly
- Gradual increase/decrease of controlled flows
Symptom
Unexpected Storage Tank Level Excursions
Possible Causes
- Malfunctioning level control system
- Malfunctioning overflow or improper boiler feed pump operation
- Pressure fluctuations
Comments or Possible Solutions
- Check setting and system operation
- Check overflow level and boiler feed pump operation
- See pressure fluctuations above
Symptom
Water Out of Vent
Possible Causes
- Cracked vent welds
- Improper vent piping
- Water carryover
Comments or Possible Solutions
- Repair or redesign
- Should be as short and as vertical as possible
- Reset vent flow
Symptom
Iron Oxide in Deaerator
Possible Causes
- Condensate or system corrosion
- Frequent shutdowns
- High O2
Comments or Possible Solutions
- Keep positive pressure on Deaerator
- See High O2 section above