Boiler feed pumps start up & shutdown procedure


                 Start-up Pre-check lists

  • Ensure Boiler feed pump is not in permit for maintenance works
  • Ensure all the maintenance activities on pumps are completed
  • Ensure equipment are normalized from electrical & mechanical side
  • Ensure Boiler feed pump is free from obstacles
  • Ensure enough lighting or illumination is available there
  • Ensure pump coupling is well guarded by robust coupling guard
  • Ensure Pumps local field instruments like pressure gauges, switches, vibration sensors, DP gauges are healthy
  • Ensure coupling is free to rotate

Starting procedure:

Start permissive (interlocks)

  • Ensure deaerator level is normal
  • Ensure feed pumps suction valves is open
  • Ensure cooling water line & outlet valves to bearings & mechanical seals are open and also water is circulating through the lines.
  • Ensure bearing temperatures are normal
  • Ensure bearing vibration showing DCS is zero
  • Ensure there is no alarm exists for strainer DP (differential pressure)
  • Ensure suction pressure is normal
  • Ensure discharge valve of the pump is closed
  • Ensure minimum recirculation valve or ARC valve is in open condition
  • Ensure balance leak off line valve to deaerator is open (In some valves are not provided to balance leak off line)

Start-up sequence

  • Take clearance from electrical & field person to start the pump
  • After getting the clearance from both the team, start the pump by giving minimum set point 80% if it is VFD driven.
  • Once the pump started, ensure pump will attain minimum 40% RPM in just 10 seconds (in case of journal bearing pumps).For non-journal bearing pumps speed ramp up time is not recommended specifically.
  • During speed ramp up check bearing vibrations & temperatures are normal.
  • Ensure pressure in the discharge pressure gauge is increasing slowly & has reached rated pressure at rated speed.
  • Then check the vibration, bearing temperatures & sound from pump.
  • Check & ensure the correctness of balance leak off line pressure
  • Wait for stabilization of the pump, once the pump attained rated parameters, check the motor current, temperature & vibrations & ensure they are within permissive limit.

Also recheck pump bearings vibration, temperatures & any abnormal sound from pump.

Pump normal shutdown procedure

  • For VFD driven pumps reduce the pump speed to 80% (for start delta driven pumps speed cannot be reduced)
  • Close the pump’s discharge valve
  • Then stop the pump

Do not’s for Boiler feed pumps

  • Do not rotate the pump in reverse direction, reverse direction leads the seize of pump
  • Don not run the pump if its suction water temperature is more than design/required
  • Do not operate the pump at less than 80<% load for long time to avoid damage to the bearings
  • Do not close the auto recirculation line valve
  • Do not close the balance leak off line valve (if provided)
  • Do not stop the pump with discharge valve open
  • Do not throttle the suction valve of the pump at lower load, can throttle discharge valve


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