Hoshizaki KML-325MWJ Service Manual page 19

c) WV and HGV Diagnosis: If WV is energized, check for 115VAC at CB K1 #6 (O) to
neutral (W). If 115VAC is present after PM energizes in harvest cycle, replace CB.
If 115VAC is not present, replace WV (bypassing). If HGV did not de-energize at
the end of harvest, check for 115VAC at CB K1 #2 (P) to neutral (W). If 115VAC is
present 50 sec. after PM energizes, replace CB. If 115VAC is not present, replace
HGV (bypassing).
d) PM Diagnosis: Confirm water is flowing over evaporator from PM and not WV.
If PM de-energizes once freeze begins or fails to energize after 10 sec. anti-slush,
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
#6 (R) to neutral (W) and control switch #5 (Y) to neutral (W). If 115VAC is present at
control switch #6 (R) and not at control switch #5 (Y), check control switch continuity.
Replace as needed. If 115VAC is present at control switch #5 (Y) to neutral (W),
check PM capacitor and motor winding continuity.
e) FM, FMR, and LLV Diagnosis: If FM, FMR, or 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:
For FM, check capacitor, motor winding, and blade for binding.
For FMR, check for 115VAC at the FMR junction box. If 115VAC is not present, check
icemaker wiring connections. If 115VAC is present, check for voltage at condenser
unit. If 115VAC is not present, check field wiring connections. If 115VAC is present,
check FMR capacitor, motor winding, and fan blade for binding.
For LLV, check coil voltage and continuity.
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) 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.
Specification and Performance Data Sheets." 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: 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."
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