Manual 2100-695C
Page
18 of 56
The valve can also be opened or closed using the EEV
service tool (Bard Part # 2151-021). This magnetic EEV
service tool (shown in Figure 26) is used to manually
open the EEV. To do this, remove the EEV stator coil (red
color with retaining nut on top), slide the magnetic tool
over the shaft where the stator was removed and turn in
a clockwise direction to open the valve to the full open
position (directional arrows are provided on the tool).
Opening the valve to the full open position will aid in the
refrigerant reclamation and evacuation processes.
With the stator removed, the resistance should be 40
ohms +/- 10%. There are two sets of three wires that
will have this resistance.
Reapply the EEV stator coil and retaining nut. Upon
powering the unit back up, the control board will
automatically drive the EEV back to the fully shut
position, and then back to the 20% open position
prior to starting the compressor back up. Once
the compressor starts, the control board will again
modulate the EEV position to control the system
superheat.
FIGURE 25
Overriding EEV Output
FIGURE 26
Electronic Expansion Valve (EEV) and Service Tool
EEV Service
Tool
EEV Stator
Coil
EEV
System Pressures
To view system pressure and temperatures during this
process:
1. From the Status screen, press UP or DOWN key
until Quick Menu displays Information icon
( ). Press ENTER key.
2. Press UP or DOWN keys to scroll to
EEV 1 Circuit
and
EVD 1 Compressor
screens (see Figure 7 on
page 9).
3. Reference the
Pressures
and
Temperatures
on
EVD
1 Compressor
and the
Superheat
and
Subcooling
on
EEV 1 Circuit
.
Suction Pressure Transducer
The unit has a pressure transducer installed on the
suction line between the evaporator coil and compressor.
The transducer is used for system monitoring of suction
system pressures. The sensor is used with the suction
temperature sensor to provide a real time superheat
calculation that determines the EEV position.
This sensor can be verified and adjusted by:
1. Press MENU key to go to the Main Menu screen.
2. Press UP or DOWN keys and ENTER key to enter
TECHNICIAN password 1313.
3. Press UP or DOWN keys to scroll to
I/O Config
;
press ENTER key.
4. Press UP or DOWN keys to scroll to
Liquid Pr
Sensor C9
.
5. Verify the measurement displayed on screen is
accurate (see Figure 27).
6. If the measurement needs to be adjusted, apply an
offset value by pressing ENTER to scroll to
Offset
.
7. Press UP or DOWN keys to adjust the offset.
8. The update will not take effect until the cursor is
moved out of the
Offset
parameter.
9. Once adjusted, press the ESCAPE key several
times to return to Main Menu screen.
FIGURE 27
Adjusting Suction Pressure Transducer Values