Hoshizaki KM-320MAH manual

Hoshizaki “A Superior Degree of Reliability” www .hoshizaki.com Models KM-320MAH KM-320MWH Modular Crescent Cuber Hoshizaki America, Inc. Number: 73132 Issued: 1-24-2006 Revised: 11-30-2006 S E RV I C E M A N U A L[...]

2 IMPOR T ANT Only qualified ser vice technicians should attempt to ser vice or maintain this icemaker . No such ser vice or maintenance should be under taken until the technician has thoroughly read this Ser vice Manual. HOSHIZAKI provides this man ual primar ily to assist qualified ser vice technicians in the ser vice and maintenance of the ice[...]

3 Please re vie w this manual. It should be read carefully bef ore the icemak er is ser viced or maintenance operations are perf or med. Only qualified ser vice technicians should ser vice and maintain the icemaker . This manual should be made a v ailab le to the technician prior to ser vice or maintenance. CONTENTS I. Specifications ............[...]

4 K. Remov al and Replacement of Pump Motor ................................................................ 42 L. Remov al and Replacement of Spra y T ubes ................................................................. 42 M. Remov al and Replacement of W ater Regulating V alve – W ater-Cooled Model Only . 43 N. Adjustment Of W ater Regulating[...]

5 I. Specifications A. KM-320MAH (air-cooled) Note: We reserve the right to make changes in specifications and design without prior notice. SPECIFICATION NO. 05A013 ISSUED: 11/29/2005 ITEM : HOSHIZAKI MODULAR CRESCENT CUBER MODEL: KM-320MAH AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 9.7 A ( 5 Min. Freeze AT 104°F / WT 80°F) MINIMUM CIRCUIT AMPACITY 20[...]

6 AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 8.2 A ( 5 Min. Freeze AT 104°F / WT 80°F) MINIMUM CIRCUIT AMPACITY 20 A MAXIMUM FUSE SIZE 20 A APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F) PER 24 HR. Temp.(°F) 50 70 90 lbs./day ( kg/day ) 70 *352 (160) 348 (158) 324 (147) Reference without *marks 80 349 (158) 342 (155) 309 (140) 90 348 (158) *337 ([...]

7 II. General Information A. Construction 1. KM-320MAH (air-cooled) Spra y T ubes W ater Supply Inlet Hot Gas V alve Expansion V alve F an Motor Drier Compressor Control Bo x (shown tr ansparent to allow vie w of other components) Control Switch Bin Control Ther mostat Float Switch W ater Pump Ev aporator Condenser Cleaning V alve[...]

8 2. KM-320MWH (water-cooled) W ater Regulator Spra y T ubes W ater Supply Inlet Hot Gas V alve Expansion V alve Drier Compressor Control Bo x (shown tr ansparent to allow vie w of other components) Control Switch Bin Control Ther mostat Float Switch W ater Pump Ev aporator Condenser Cleaning V alve[...]

9 B. Controller Boar d 1. Solid-State Control • A HOSHIZAKI e xclusiv e solid-state control is emplo yed in KM-320MAH and KM-320MWH Modular Crescent Cubers. • A printed circuit board (hereafter called "controller board") includes a stable and high quality control system. • All models are pretested and f actor y-adjusted. 2. Controll[...]

10 c) High T emperature Safety - 127 ± 7°F (53 ± 4°C) The temperature of the suction line in the refrigerant circuit is limited b y the high temperature saf ety . During the defrost cycle the ev aporator temperature rises. The ther mistor senses 48°F (9°C) and star ts the defrost timer . After the defrost timer counts down to z ero , the nor [...]

11 The green LEDs 1-4 represent the corresponding rela ys and energize and sequence 5 seconds from initial star tup as follo ws: Sequence Step LED Time LEDs are Lit Min. Max. A vg. 1 Minute Fill Cycle 4 60 seconds Har v est Cycle 1, 4, and 2 2 minutes 20 minutes 3 to 5 minutes F reeze Cycle 1 5 minutes 60 minutes 30 to 35 minutes Re v erse Pump Out[...]

12 The application s witch located between rela y X3 & X4 must be set to match the original board application. Place this switch in the ALP position if there is no white wire supplied to the K1 connector . If there is a white wire, place the s witch in the C position. If this switch is placed in the wrong position either the compressor contacto[...]

13 3. Sequence IMPOR T ANT 1. Board ne ver accepts defrost completion signal within the first 2 minutes in defrost cycle. 2. Defrost cycle time is limited to 20 minutes e v en if defrost timer does not stop counting. 4. Defrost timer stops counting. Defrost cycle is completed and freeze cycle star ts . 1. Unit energized and control s witch to "[...]

14 2nd Cycle and after with pump drain 4. Defrost timer stops counting. Defrost cycle is completed and freeze cycle star ts . 2. Drain timer stops counting. Pump drain is completed. 5. After the first 5 minutes in freeze cycle . Ready to complete freeze cycle when float s witch circuit opens. IMPOR T ANT 1. Board ne ver accepts defrost completion s[...]

15 2nd Cycle and after with no pump drain 3. Defrost timer stops counting. Defrost cycle is completed and freeze cycle starts. 4. After the first 5 minutes in freeze cycle . Ready to complete freeze cycle when float s witch circuit opens. IMPOR T ANT 1. Board ne ver accepts defrost completion signal within the first 2 minutes in defrost cycle. 2. D[...]

16 4. Controls and Adjustments The dip s witch is f actor y-adjusted to the follo wing positions: Dip Switch No . 1 2 3 4 5 6 7 8 9 10 KM-320MAH OFF OFF OFF ON ON ON OFF OFF OFF OFF KM-320MWH OFF OFF OFF ON ON ON OFF OFF OFF OFF Switch Nos. 1 and 2: Used f or adjustment of the defrost timer . The defrost timer star ts counting when the ther mistor [...]

17 a) Defrost Contr ol A ther mistor (semiconductor) is used f or a defrost control sensor . The resistance varies depending on the suction line temperatures . The ther mistor detects the temperature of the e v aporator outlet to star t the defrost timer . No adjustment is required. If necessar y , check f or resistance between thermistor leads, an[...]

18 c) Drain Timer The drain timer is f actor y-adjusted, and no adjustment is required. Dip Switch Setting Time (seconds) No . 3 No . 4 T1 T2 OFF OFF 10 150 ON OFF 10 180 OFF ON 10 120 ON ON 20 180 T1: Time to drain the water tank T2: Time to restrain defrost completion d) Drain Counter The drain counter is f actor y-adjusted to drain the water tan[...]

19 e) Freeze Timer CA UTION Adjust to proper specification, or the unit ma y not operate correctly . The freeze timer is f actor y adjusted and no adjustment is required. The setting deter mines the maximum allo wed freez e time to pre vent possib le freez e-up issues. Dip Switch Setting Time (minutes) No . 9 No . 10 OFF OFF 60 OFF ON 50 ON OFF 70[...]

20 3) Reconnect the float s witch connector to the controller board. After the first 5 minutes of the freeze cycle , disconnect the float s witch leads from the controller board. At this point, the unit should star t the defrost cycle. 4) After step 3), de-energize the unit and confirm that the defrost timer is in the minimum position. Disconne[...]

21 III. T echnical Inf ormation A. W ater Cir cuit and Refrigerant Circuit 1. KM-320MAH[...]

22 2. KM-320MWH[...]

23 B. Wiring Diagram 1. KM-320MAH, KM-320MWH Note: Pressure Switch KM-320MAH Cut-out 412 PSIG Cut-in 327 ± 21 PSIG +21 0 Note: Pressure Switch KM-320MWH Cut-out 384 PSIG Cut-in 284 ± 21 PSIG +21 0[...]

24 C. Timing Chart *1 The icemaker does not complete a defrost cycle in the first 2 or 3 min utes. See "II.B .4. Controls and Adjustments."[...]

25 *1 The pump motor waits f or 2 seconds before starting a drain cycle. See "II.B.4. Controls and Adjustments." *2 The icemaker does not complete a defrost cycle in the first 2 or 3 min utes. See "II.B .4. Controls and Adjustments."[...]

26 D . P erformance Data 1. KM-320MAH Note: Pressure data is recorded at 5 minutes into freez e cycle. The data not in bold should be used f or ref erence only . W e reser v e the right to make changes in specifications and design without prior notice. PERFORMANCE DATA NO. 05A013 ISSUED: 11/29/05 ITEM : HOSHIZAKI MODULAR CRESCENT CUBER MODEL: KM-3[...]

27 2. KM-320MWH Note: Pressure data is recorded at 5 minutes into freez e cycle. The data not in bold should be used f or ref erence only . W e reser v e the right to make changes in specifications and design without prior notice. PERFORMANCE DATA NO. 05A014 ISSUED: 11/29/05 ITEM : HOSHIZAKI MODULAR CRESCENT CUBER MODEL: KM-320MWH 70/21 352 160 34[...]

28 IV . Ser vice Diagnosis A. No Ice Production Prob lem P ossible Cause Remedy [1] The icemaker will not star t. a) P ower Supply 1. OFF position. 1. Mov e to ON position. 2. Loose connection. 2. Tighten. 3. Bad contacts. 3. Check f or continuity and replace. 4. V oltage too high. 4. Check and get recommended voltage . b) Fuse (Inside fused discon[...]

29 Prob lem P ossible Cause Remedy j) W ater Supply Line 1. W ater supply off and water supply cycle does not finish. 1. Check and get recommended pressure. 2. Condenser w ater pressure too low or off and pressure control opens and closes frequently to finally operate high temperature saf ety . 2. Chec k and get recommended pressure. k) W ater So[...]

30 Prob lem P ossible Cause Remedy c) Ov erload Protector 1. Bad contacts. 1. Check f or continuity and replace. 2. V oltage too low . 2. Increase voltage . 3. Refrigerant ov ercharged or undercharged. 3. Recharge. 4. Line valv e continues to close in freez e cycle and ov er load protector operates. 4. Check line v alv e’ s operation in freeze cy[...]

31 Prob lem P ossible Cause Remedy d) Pump Motor 1. Motor winding opened. 1. Replace. 2. Bearing wor n out. 2. Replace. 3. Wiring to pump motor . 3. Check f or loose connection or open, and replace. 4. Defectiv e capacitor . 4. Replace. 5. Defectiv e or bound impeller . 5. Replace and clean. 6. Mechanical seal worn out. 6. Check and replace . e) Co[...]

32 Prob lem P ossible Cause Remedy c) Controller Board 1. Defectiv e. 1. See "II.B.5. Checking the Controller Board." [2] All ice formed on e v aporator does not f all into bin in har v est cycle. a) Evapor ator 1. Scaled up. 1. Clean. b) W ater Supply Line 1. W ater pressure too low . 1. Check and get recommended pressure. c) Water Filte[...]

33 C. Low Ice Pr oduction Prob lem P ossible Cause Remedy [1] F reeze cycle time is long. a) See char t A.[3] and check dir ty air filter or condenser , ambient or water temperature, w ater pressure, water regulator , and refrigerant charge. b) See char t B.[1] and chec k float s witch, water solenoid v alve and controller board. [2] Har vest cyc[...]

34 V . Remov al and Replacement of Components IMPOR T ANT Ensure all components, f asteners and thumbscrews are securely in place after the equipment is ser viced. IMPOR T ANT 1. The P oly ol Ester (POE) oils used in R-404A units can absorb moisture quickly . Theref ore it is impor tant to pre v ent moisture from entering the system when replacing [...]

35 8) If necessar y , add any remaining charge to the system through the lo w-side. Use a throttling v alv e or liquid dispensing de vice to add the remaining liquid charge through the low-side access por t with the unit running. 9) Close the two refrigerant access v alv es and disconnect the hoses and ser vice manif old. 10) Cap the access v alv e[...]

36 C. Remov al and Replacement of Compressor IMPOR T ANT Alwa ys install a new drier e v er y time the sealed refrigeration system is opened. Do not replace the drier until after all other repair or replacement has been made. Note: When replacing a compressor with a defectiv e winding, be sure to install the new start capacitor and star t rela y su[...]

37 D . Remo v al and Replacement of Drier IMPOR T ANT Alwa ys install a new drier e v er y time the sealed refrigeration system is opened. Do not replace the drier until after all other repair or replacement has been made. 1) T urn off the power supply . 2) Remov e the panels. 3) Recov er the refr igerant and store it in an appro v ed container . 4[...]

38 6) Braz e the ne w e xpansion v alv e , with nitrogen gas flowing at a pressure of 3 to 4 PSIG. W ARNING 1. Do not heat the wall. Place a steel barr ier f or protection. 2. Alwa ys protect the v alv e body b y using a damp cloth to pre vent the v alv e from ov erheating. Do not braze with the v alve body e xceeding 250°F (121°C). 7) Install a[...]

39 7) Install a new drier . 8) Check f or leaks using nitrogen gas (140 PSIG) and soap bub b les. 9) Ev acuate the system and charge it with refrigerant. See the nameplate for the required refrigerant charge. 10) Cut the leads of the solenoid allowing enough lead length to reconnect using closed end connectors. 11) Connect the new solenoid leads . [...]

40 H. Remov al and Replacement of Thermistor CA UTION 1. F ragile , handle v er y carefully . 2. Alwa ys use a recommended sealant (High Ther mal Conductiv e T ype), Model KE4560R TV manuf actured by SHINETSU SILICONE, P ar t Code 60Y000-11, or P ar t Code 4A0683-01 equiv alent. 3. Alwa ys use a recommended f oam insulation (Non-absorbent T ype) or[...]

41 I. Remov al and Replacement of Fan Motor Note: When replacing a fan motor with def ective winding, it is recommended that a ne w capacitor be installed. 1) T urn off the power supply . 2) Remov e the panels. 3) Remov e the closed end connectors from the fan motor leads . 4) Remov e the fan motor br ac ket and f an motor . 5) Install the new f an[...]

42 K. Remov al and Replacement of Pump Motor 1) T urn off the power supply . 2) Remov e the front panel. 3) Remov e the base cov er . 4) Drain the w ater tank b y removing one end of the pump tubing. 5) Replace the remov ed par ts in their correct positions . 6) Disconnect the pump suction and discharge hoses. 7) Remov e the closed end connectors f[...]

43 M. Remov al and Replacement of W ater Regulating V alve – W ater-Cooled Model Onl y IMPOR T ANT Alwa ys install a new drier e ver y time the sealed refrigeration system is opened. Do not replace the drier until after all other repair or replacement has been made. 1) T urn off the power supply . 2) Close the water supply line shut-off v alve . [...]

44 N. Adjustment Of W ater Regulating V alve – W ater-Cooled Model Onl y The water regulating v alve (also called "w ater regulator") is f actor y-adjusted. No adjustment is required under nor mal use. Adjust the water regulator , if necessar y , using the f ollo wing procedure. 1) Attach a pressure gauge to the high-side line of the sy[...]

45 VI. Cleaning and Maintenance Instructions IMPOR T ANT Ensure all components, f asteners and thumbscrews are securely in place after any maintenance or cleaning is done to the equipment. A. Preparing the Icemaker for Long Stora ge W ARNING When shutting off the icemaker f or an e xtended time, dr ain out all water from the water tank and remo v e[...]

46 3. Drain the potable w ater tank: 1) T urn off the power supply . 2) Mov e the control switch to the "OFF" position. 3) Drain the w ater tank b y removing the base cov er and one end of the pump tubing. See Fig. 4. 4) Replace the remov ed par ts in their correct positions . 5) Remov e all ice from the storage bin, and clean the storage[...]

47 B. Cleaning and Sanitizing Instructions IMPOR T ANT Ensure all components, f asteners and thumbscrews are securely in place after any maintenance or cleaning is done to the equipment. W ARNING 1. HOSHIZAKI recommends cleaning this unit at least once a year . More frequent cleaning, how e v er , ma y be required in some existing w ater conditions[...]

48 1. Cleaning Procedure 1) Dilute appro ximately 16 fl. oz. of the recommended cleaner Hoshizaki "Scale A wa y" or "LIME-A-W A Y" (Economics Laborator y , Inc.) with 3 gal. of water . 2) Remov e all ice from the ev aporator and the storage bin. Note: T o remo v e cubes on the e vaporator , tur n off the power supply and turn i[...]

49 15) Mov e the control switch to the "ICE" position. 16) Close the cleaning v alv e. Note: The icemaker will not oper ate unless the cleaning v alv e is completely closed. 17) Replace the front panel in its correct position. 18) T urn on the power supply to fill the w ater tank with water . 19) T urn off the power supply after 3 min ut[...]

50 C. Maintenance IMPOR T ANT This icemaker m ust be maintained individually , ref erring to the instr uction manual and labels pro vided with the icemak er . 1) Stainless Steel Exterior T o pre vent corrosion, wipe the e xterior occasionally with a clean and soft cloth. Use a damp cloth containing a neutral cleaner to wipe off oil or dir t build u[...]