Sterlco Royal Series Compact Temperature Control Unit - Manual (Page 36)

Page 36 Royal Series Water Temperature Control Units
TCU systems provide temperature control on processes by
directly heating the process water and injecting cooling water
into the process water.
When the unit is energized, the pump starts and a one minute
vent sequence opens the cooling/vent valve to remove any air
trapped in the process piping.
If the cooling water supply pressure is insufficient, the low
cooling water pressure cutout switch (set at 16 psig, 10 psig
differential [110.32 kPa/1.10 bars, 68.95 kPa/0.69 bars
differential]) opens, the
LOW WATER PRESSURE indicator
lights, and the unit does not operate until the pressure is 16 psig
(110.32 kPa/1.10 bars) or more. You need at least 16 psig
(110.32 kPa/1.10 bars) for the best cooling capacity and to
prevent water boiling in the process circuit at high
temperatures, particularly at the pump suction.
After venting, the microprocessor controller monitors the TO
PROCESS RTD probe, cycling open the cooling/vent valve to
discharge warm water or energizing the immersion heater to
maintain the process set temperature.
5-5 Checking Motor Rotation Direction
Check for correct pump rotation direction by looking at the top of
the motor. Press the
START button and the STOP button, and note
the direction that the motor turns. Rotation should be clockwise
when viewed from the motor end.
Note: Make sure that a qualified electrician performs the
following steps.
To change rotation direction:
1. Disconnect and lock out power at the fused disconnect.
2. Reverse any two incoming leads at the power terminal
blocks.
3. Do not switch leads at the motor or motor starters.
5-6 Shutting Down the Temperature Control Unit
Cool the unit down by selecting a set point of zero ( 0 ). Let the
unit stabilize at one temperature close to the incoming water
temperature, then press the
STOP button. Now press the VENT
button to relieve any remaining pressure in the system.