Sterlco 6017 Series, Operation And Installation Manual

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6017 Series Hot Oil Large Temperature Control Units Page 25
Figure 4
Custom Process Piping
The optimum location for venting is on the top of the overhead return piping above the unit. The
customer is encouraged to add an extra vent (Blow-Off) valve at this point. With this new Blow-
Off Valve location the return valve and internal blow-off valve should be closed completely
during venting. Otherwise air could be pulled into the piping by gravity instead of being
removed.
The frequent process disconnection scenario has the vent line connected to the process side of
the two isolation valves. This allows the disconnected process to be vented without
contaminating the rest of the piping and unit to be contaminated with air. This is accomplished
by the following steps once the process is reconnected to the unit and the isolation valves are still
closed.
Note: during this process the internal blow-off valve is closed and the return valve can be open.
1.) Open the external vent valve.
2.) Open the isolation valve that is delivering oil to the process from the unit. Leave the
isolation valve that is returning the oil from the process to the unit closed.
3.) Wait for all of the process to fill with heat transfer fluid and push the air and back to the
reservoir.
4.) Once all of the air has been replaced with fluid, and only oil is being dumped into the
reservoir; close the vent valve.
5.) Open the isolation valve that is returning the oil from the process.