Vahterus Plate - General Shut down; Start-Up and Shut down of Steam Applications

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Tobegintheheatexchangerprocess,followstepsa–f,startingrstonthecoldside.
Then repeat for the hot side.
a) Closetheinletshut-ovalve.
b) Opentheoutletshut-ovalve.
c) Open the vent valve, if the heat exchanger is provided with one; otherwise vent
from the nearest vent valve to the heat exchanger in the pipework.
d) Start the pump.
e) Slowly open the inlet valve according to the instructions.
f) Close the vent valve when all the air has been removed from the system. If the
heat exchanger is working properly, it can used on an ongoing basis.
Openable model:
When the openable model is being started up, always check the bolts and tighten them
if necessary.
4.3 General shut down
Iftheheatexchangerprocessistobehalted,followstepsa-dbelow,startingrston
the hot side. Then repeat for the cold side.
a) Slowly close the inlet valves.
b) Switchothepumps.
c) Close the outlet valves.
d) Drain and vent the heat exchanger.
Graduallydecreasetheowonthehotsideuntilitstopscompletely.Thenclosethe
cold side.
NB
Valves must be set to open gradually. Sudden opening and closing of the valves will
subject the exchanger to thermal shock and may cause material fatigue. In steam ap-
plications,neverleavethehotsideonwhentheliquidsideisturnedo.Turnthesteam
OFF rst and ON last. In steamprocesses, it must be noted that cooling water side
pressure must be higher than steam pressure in the condensate side controlled unit.
If pressure is lower, cooling water can evaporate and there is a risk of plate damage.
4.4 Start-up and shut down of steam applications
Itisnecessarytoventairofromtheheatexchangerbeforestartingtheoperation.The
following procedure should be followed:
Air venting process
1. Closetheinletshut-ovalve.
2. Opentheoutletshut-ovalve.
3. Open the vent valve, if the heat exchanger is provided with one; otherwise, vent
from the nearest vent valve to the heat exchanger in the pipeline.