Service Manual

19
d) PM Diagnosis: Conrm water is owing over evaporator from PM and not WV. If PM
de-energizes once freeze begins, check for 115VAC at CB K1 #4 (R) to neutral (W).
If 115VAC is not present, replace CB. If 115VAC is present and PM is de-energized,
check for 115VAC at control switch #5 (W/R) to neutral (W). If 115VAC is present at
CB K1 #4 (R) and not at control switch #5 (W/R), check control switch continuity
between #5 (W/R) and #4 (R). Replace as needed. If 115VAC is present at control
switch #5 (W/R) to neutral (W), check PM capacitor and motor winding continuity.
e) LLV Diagnosis: If LLV does not energize, check for 115VAC at CB K1#3 (BK) to
neutral (W). If 115VAC is not present, replace CB. If 115VAC is present, check coil
voltage and continuity.
f) Refrigerant Pressures, HM, and TXV Diagnosis:
Refrigerant Pressures: If evaporator is still not cooling, check refrigerant pressures.
See "VIII.A. Specication and Performance Data."
HM (if applicable): Check HM operation. If refrigeration pressures are above HM
setpoint and HMis bypassing, replace HM.
TXV: 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) WRV Diagnosis: WRV is factory set and generally no adjustment is required.
IfWRV fails to open in freeze, check for proper refrigerant pressures. See "VIII.A.
Specication and Performance Data." If refrigerant pressures are correct and WRV
does not open, adjust or replace as needed. See "IV.C. Water Regulating Valve
Adjustment (water-cooled models)."
h) Freeze Termination Diagnosis (FS): 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.F. 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. Specication and Performance Data."
i) Short Freeze Cycle Diagnosis: Conrm water tank lls and overows during ll and
harvest cycles. If not, check water supply lters, 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 (water owing 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.F. Float Switch Check and Cleaning." for erratic FS.