Frick QUANTUM Maintenance Manual page 10

S90-010 M
Page 10
SYMPTOM
COMPRESSOR WILL ONLY PARTIALLY LOAD*
(Compressor that steps on Capacity)(Continued)
SLIDE VALVE DOES NOT LOAD and/or UNLOAD*
SLIDE STOP DOES NOT INCREASE and/or
DECREASE*
Some Compressor Models:
Slide Stop Increase = Decrease to 3.5 Vi
Slide Stop Decrease = Decrease to 2.2 Vi
LIQUID INJECTION SOLENOID DOES NOT
ENERGIZE* (Liquid Injection Refrigerant Cutout -
LICO)
FRICK QUANTUM CONTROL PANEL
MAINTENANCE
PROBABLE CAUSES and CORRECTIONS
Inspect the compressor unloading ports for worn or improperly seated
parts.
Verify that the Slide Valve is in the AUTO mode and that capacity
control is calling for load and/or unload.
Output 5 (MOD 5) controls the Slide Valve Load Solenoid. If LED (D5)
for Output 5 (MOD 5) is on, check for the proper panel voltage be-
tween position 4 and 1 on the P2 DIO connector on Digital I/O board
#1. If the proper voltage is not found, check the fuse (F5) and if the
fuse is OK, check the output module (MOD 5). If the voltage was OK,
check for the proper voltage between position 1 on the P2 DIO con-
nector and position 17 on the terminal strip. If voltage is OK, check for
the proper voltage between position 17 and 2 on the terminal strip. If
the voltage is OK, check the solenoid valve.
Output 6 (MOD 6) controls the Slide Valve Unload Solenoid. If the
LED (D1) for Output 6 (MOD 6) is on, check for the proper panel
voltage between position 4 and 2 on the P2 DIO connector on Digital
I/O board #1. If the proper voltage is not found, check the fuse (F6)
and if the fuse is OK, check the output module (MOD 6). If the voltage
was OK, check for the proper voltage between position 2 on the P2
DIO connector and position 16 on the terminal strip. If voltage is OK,
check for the proper voltage between position 16 and 2 on the termi-
nal strip. If the voltage is OK, check the solenoid valve.
NOTE: Verify that the proper capacity control setpoint has been
programmed.
Verify that the Slide Stop is in the AUTO mode and that the VI Ratio is
calling for a VI increase or decrease.
Output 7 (MOD 7) controls Slide Stop Increase Solenoid. If the LED
(D7) for Output 7 (MOD 7) is on, check for the proper panel voltage
between position 4 and 5 on the P2 DIO connector on Digital I/O
board #1. If the proper voltage is not found, check the fuse (F7) and if
the fuse is OK, check the output module (MOD 7). If the voltage was
OK, check for the proper voltage between position 5 on the P2 DIO
connector and position 15 on the terminal strip. If voltage is OK, check
for the proper voltage between position 15 and 2 on the terminal strip.
If the voltage is OK, check the solenoid valve.
Output 8 (MOD 8) controls the Slide Stop Decrease Solenoid. If the
LED (D8) for Output 8 (MOD 8) is on, check for the proper panel
voltage between position 4 and 6 on the P2 DIO connector on Digital
I/O board #1. If the proper voltage is not found, check the fuse (F8)
and if the fuse is OK, check the output module (MOD 8). If the voltage
was OK check for the proper voltage between position 6 on the P2
DIO connector and position 14 on the terminal strip. If voltage is OK,
check for the proper voltage between position 14 and 2 on the termi-
nal strip. If the voltage is OK, check the solenoid valve.
Verify that the Liquid Injection TXV is modulating properly and not
feeding excessive liquid to LICO the compressor. This solenoid
SHOULD be de-energized when the compressor is off. This solenoid
should be energized if the oil temperature equals or exceeds the "Oil
Temperature On At" setpoint for the delay time.