Hoshizaki SRK-10J Service Manual page 17

f) Refrigerant Pressures, HM, and TXV Diagnosis: If evaporator is still not cooling,
check refrigerant pressures. See "VIII.A. Specification and Performance Data
Sheets." Next, check HM operation. If refrigeration pressures are above HM setpoint
and HM is bypassing, replace HM. Check TXV for proper operation. Remove TXV
bulb and hold it in your hand, refrigerant low-side pressure should rise, place
TXV bulb in ice water, refrigerant low-side pressure should drop. A 10 to 15 pound
pressure swing between warm and cold conditions indicate a good TXV. If a 10 to 15
pound swing is not present, replace TXV.
g) Freeze Termination Diagnosis: After 5 min. in freeze, disconnect CB K5 FS
connector. 15 sec. later appliance should switch out of the freeze cycle (15 second
delay after FS opens before terminating the freeze cycle). If appliance remains in
freeze longer than 15 sec. after FS removed, replace CB. If appliance switches with
FS removed but would previously not switch out of freeze with FS connected (long
freeze - 3 beep alarm), see "II.E. Float Switch Check and Cleaning."
Note: Normal freeze cycle will last 20 to 40 min. depending on model and conditions.
Cycle times and pressures should follow performance data provided in this manual.
See "VIII.A. Specification and Performance Data Sheets."
h) Short Freeze Cycle Diagnosis: Confirm water tank fills and overflows during
1 min. fill and harvest cycles. If not, check water supply filters, shut-off valve, WV
screen. If water tank empties before 5 min. timer terminates and freeze cycle is
short, check that CV is not leaking by or energized (water flowing down the potable
drain). If CV is leaking by, remove and clean CV, replace rubber seat and spring
if necessary. If water tank is full, see "II.E. Float Switch Check and Cleaning." for
erratic operating FS.
7) Pump-Out Cycle – LEDs 1, 3, and 2 are on (10/20 second pump-out). Timing of the
first pump-out is determined by S4 dip switch 5. See the table below.
S4 Dip Switch Setting
Comp, FM*, and FMR continue, HGVs energize.
Note: If S4 dip switch 3 & 4 are set to 3 off and 4 on, LED 4 turns on and WV and
X11 relay energize, energizing X10 relay. NOTICE! S4 dip switch 3 & 4 must not be
set to 3 off and 4 on. Otherwise, PM will rotate in freeze cycle direction instead
of pump-out direction. FM and LLVs de-energize. PM stops for 2 sec., then reverses
for 10/20 sec. depending on pump-out timer (S4 dip switch 3 & 4) setting. When the
pump-out timer terminates, pump-out is complete. The pump-out frequency control
(S4 dip switch 5) is factory set, and generally no adjustment is required. However, the
pump-out frequency control can be set to have a pump-out occur every 10 cycles or
every cycle. For details, see "III.C.4. Pump-Out Frequency Control (S4 dip switch 5)."
Control Board Settings
Pump-Out Frequency
No. 5
OFF Every 10 cycles
ON Every cycle
17
Control Board
After 11th freeze cycle
After 2nd freeze cycle