Page 16
– Bulletin 100-50-5.2
Refer to Appendix I - Wiring Diagram for sensor locations.
Mount the Pressure Transducer
1. Position the suction return gas pressure access port near
the outlet of the heat exchanger.
2. Verify that the pressure range matches the expected sys-
tem operating pressure (i.e 0-150 psig, 0-300 psig, etc).
3. Install transducer on access port at 12 o’clock, minimiz-
ing distance from temperature sensor. Check for leaks.
4. For safety, ensure Schrader core is installed in access
fitting (only if ¼” SAE is used).
Use caution when re-
moving Schrader cap to avoid contacting expanding
refrigerant.
5. Connect pressure transducer cable to transducer.
6. Route and secure transducer cable away from hot surfaces
and high power A/C voltage lines.
7. Attach wires to the Subcool Control.
8. Ensure pressure range and type (i.e gauge or absolute) are
configured properly in the Subcool Controller, See Sec-
tion 2 - SETUP,
page 4.
9. After startup, use a gauge set to verify proper pressure
reading through the Subcool Control. An improperly
installed Schrader core can cause erroneous pressure
readings.
10. Check for leaks after system is in operation.
Mount the Temperature Sensors – Suction and
Liquid
1. Per Appendix I - Wiring Diagram, page 15, measure and
mark locations on copper pipe. Position sensors 10-14
inches from the heat exchanger on a free-draining hori-
zontal line.
2. Remove all insulation and adhesives at the marked loca-
tion. Using Scotch-Brite
TM
, clean the copper line to remove
oxides and dirt. This will increase sensor accuracy.
3. Fasten the temperature sensors in orientation shown in
Figure 6
. Carefully note the locations of temperature
sensors for Suction Gas and Liquid.
• Mount the suction temperature sensor on the suction
line after the heat exchanger, near the pressure trans-
ducer.
• Mount the subcool liquid temperature sensor on the
subcooled liquid outlet.
4. Attach and secure temperature sensor cables, routing
them away from hot surfaces and high power A/C volt-
age lines.
5. Ensure that the Subcool Control is configured properly
(i.e 2K or 3K sensor selection), See Section 2 - SETUP,
page 4.
NOTE: 2K and 3K sensors have approximately
1.9kΩ and 2.8kΩ, respectively, at 80°F measured
across the sensor wires.
6. Wrap temperature sensors and copper tube with foam
insulation to minimize ambient temperature effects, See
Figure 7.
APPENDIX J - Sensor Installation
Figure 6 - Temperature Sensor Positioning
Temperature sensor should be mounted at either 4 or
8 o’clock, on a free-draining horizontal line.
Figure 7 - Cutaway of Pipe Insulation
2K sensor shown
WARNING: Ensure that “Suction” and “Liquid” tem-
perature sensor locations are not reversed. Severe
system damage may occur if these two sensor
locations are interchanged.
Figure 8 - Temperature Sensors
2K sensor
3K sensor
