Hoshizaki DKM-500BAH manual

Hoshizaki “A Superior Degree of Reliability” www .hoshizaki.com Model DKM-500BAH Crescent Cube Icemaker / Dispenser Hoshizaki America, Inc. S e r v i c e M a n u a l ™ Number: 73138 Issued: 9-20-200 6[...]

2 IMPOR T ANT Only qualified ser vice technicians should attempt to ser vice or maintain this unit. 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 unit. Sh[...]

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

4 III. T echnical Information ...................................................................................................... 19 A. W ater Circuit and Refr igeration Circuit ........................................................................ 19 B. Wir ing Diagr am .........................................................................[...]

5 AC SUPPLY VOLTAGE 115/60/1 AMPERAGE 13.3 A ( 5 Min. Freeze AT 104°F / WT 80°F) MINIMUM CIRCUIT AMPACITY 15 A MAXIMUM FUSE SIZE 15 A APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F) PER 24 HR. Temp.(°F) 50 70 90 lbs./day ( kg/day ) 70 *466 (211) 448 (203) 420 (191) Reference without *marks 80 453 (205) 425 (193) 395 (179) 90 448 (203) *406 [...]

6 II. General Information A. Construction 1. DKM-500BAH Spra y T ubes W ater Supply Inlet Condenser Condenser F an Motor Control Bo x Drier Hot Gas V alve Compressor Float Switch W ater Pump Mechanical Bin Control Control Switches Expansion V alv e Agitator Bin Gear Motor Assembly Solenoid Assembly Drain P an F ront Panel Shutter Dispense Switch Sp[...]

7 B. Sequence of Operation The steps in the sequence are as outlined below . When power is supplied, a 5 second dela y occurs at star tup . Note that the order of the LEDs from the outer edge of the board is 1, 4, 3, 2. 1. One Minute Fill Cycle LED 4 is on. WV opens and the fill period begins. After 1 minute , the board chec ks f or a closed F/S. [...]

8 DKM-500B AH Sequence Flow Char t and Component Operation 1. One Minute Fill Cycle 4. Pump-Out Cycle Cycle Steps WV Energized F/S open F/S closed Comp energized HGV energized WV continues Thermistor temp reaches 48°F (9°C) (3.9 k Ω or less) Har v est timer star ts F/S open Comp continues HGV de-energized WV de-energized PM energized FMS energi[...]

9 C. Control Boar d • A HOSHIZAKI e xclusiv e solid-state control is emplo yed in the DKM-500BAH Crescent Cube Icemaker / Dispenser . • All units are pretested and f actor y-adjusted. CA UTION 1. F ragile , handle v er y carefully . 2. A control board contains integrated circuits, which are susceptib le to failure due to static discharge. It is[...]

10 Control Boar d P ar t Number 2A1410-01 (f actor y); 2A1410-02 (service) T ype HOS-001A (Control Products - 10 Pin) Output T est Switch (used to test rela ys on board) Connector K3 Har v est Control (thermistor) Connector K4 Mechanical Bin Control Microprocessor (board re vision le vel indicated by last 2 digits on label) Connector K5 Float Switc[...]

11 2. Features a) Maximum W ater Supply P eriod – 6 minutes Inlet water v alve opening, in the harvest cycle , is limited by the harvest timer . The water v alv e cannot remain open longer than the maximum period. The water v alve can close in less than six minutes if the harvest cycle is completed. b) Harvest Backup Timer and Freeze Timer The ha[...]

12 f) LED Lights and A udible Alarm Saf eties The red LED indicates proper control v oltage and will remain on unless a control v oltage problem occurs . At star tup a 5 second delay occurs while the board conducts an internal timer check. A shor t beep occurs when the power s witch is tur ned OFF . The green LEDs 1 through 4 energiz e and sequence[...]

13 No . of Beeps (e v er y 3 sec.) T ype of Alarm Notes 6 Low V oltage (92V ac ±5% or less) Red LED will tur n off if v oltage protection operates . The control v oltage saf eties automatically reset when v oltage is corrected. 7 High V oltage (147V ac ±5% or more) Legend: Comp –compressor ; D V –Drain V alve; FMS –self-contained f an motor[...]

14 Check a thermistor f or resistance b y using the f ollowing procedure: 1) Disconnect the connector K3 on the board. 2) Remov e the ther mistor . See "V .H. Remov al and Replacement of Ther mistor ." 3) Immerse the ther mistor sensor por tion in a glass containing ice and water f or 2 or 3 minutes . 4) V erify the temperature of the gla[...]

15 e) Pump-Out Frequency Contr ol (dip s witch 5 & 6) The pump motor drains the w ater tank at the frequency set b y the pump-out frequency control. The pump-out frequency control is f actor y-adjusted to drain the w ater tank e very 10 cycles, and no adjustment is required. Howe v er , where water quality is bad and the icemaker needs a pump d[...]

16 shut down the unit. Howe v er , to pre v ent incomplete batches of ice from f or ming on the e v aporator , the control board will only shut down the machine within the first 5 minutes of the freeze cycle . If ice pushes the lev er in after the first five min utes of the freeze cycle , the control board will allow the machine to complete the [...]

17 3) Check the 115 v olt input at the 10-pin connector . Check the bro wn wire at pin #10 to a white neutral wire f or 115 volts . (Alwa ys choose a white neutral wire to estab lish a good neutral connection when chec king v oltages .) A jumper also f eeds 115 v olts into pin #7. If no v oltage is present, chec k the 115 v olt supply circuit. 4) T[...]

18 b) CIRCULA TE When the ser vice s witch is activ e and placed in the CIRCULA TE position, power is supplied to the pump only . This operation can be used to circulate cleaner f or extended periods of time ov er the outside surf ace of the e vaporator . c) W ASH This model utilizes a solenoid oper ated cleaning (b ypass) v alv e. When the ser vic[...]

19 III. T echnical Inf ormation A. W ater Cir cuit and Refrigeration Circuit 1. DKM-500BAH[...]

20 B. Wiring Diagram 1. DKM-500BAH * Pressure Switch Cut-out 412.5 PSIG Cut-in 327±21.3 PSIG * (Service Relay) (12V)[...]

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

22 *1 The pump motor waits f or 2 seconds before starting a drain cycle. See "II.C.3. Controls and Adjustments." *2 The icemaker does not complete a defrost cycle in the first 2 or 3 min utes. See "II.C .3. Controls and Adjustments."[...]

23 70/21 466 211 448 203 420 191 80/27 453 205 425 193 395 179 90/32 448 203 406 184 376 170 lbs./day kg./da y 100/38 390 177 399 181 348 158 70/21 80/27 90/32 watts 100/38 70/21 110 0.42 97 0.37 88 0.33 80/27 100 0.38 80 0.30 75 0.29 90/32 97 0.37 66 0.25 59 0.22 gal./day m 3 /day 100/38 144 0.55 65 0.24 53 0.20 70/21 80/27 90/32 min. 100/38 70/21[...]

24 IV . Ser vice Diagnosis A. 10-Minute Diagnostic Pr ocedure The 10 minute chec k out procedure is basically a sequence chec k which can be used at unit star t-up or for system diagnosis . Using this check out procedure will allo w y ou to diagnose electrical system and component failures in appro ximately 10 minutes under nor mal operating condit[...]

25 conditions. Cycle times and pressures should f ollow perf or mance data provided in this manual. 6) Pump-Out Cycle (10/20 second pump out) – the compressor remains energiz ed, the hot gas v alv e energizes , the fan motor de-energiz es, the pump motor stops f or 2 seconds. The ser vice rela y energizes , restar ting the pump motor and taking w[...]

26 Prob lem P ossible Cause Remedy 4. Refrigerant ov ercharged. 4. Recharge. 5. F an not operating. 5. See char t 1. a) [6] 6. Refrigerant line or components plugged. 6. Clean and replace drier . f) T ransf or mer 1. Coil winding opened or shor ted. 1. Replace. g) Wir ing to Control Board 1. Loose connections or open. 1. Chec k for continuity and r[...]

27 Prob lem P ossible Cause Remedy c) Internal Overload Protector Open (check 1 through 3 to the right and d through f below) 1. Loose ter minal. 1. Tighten or replace. 2. V oltage. 2. Check and correct. 3. Dir ty condenser . 3. Clean. d) Star ter 1. Bad contacts. 1. Check and replace. 2. Coil winding opened. 2. Replace. e) Compressor 1. Wiring to [...]

28 Prob lem P ossible Cause Remedy b) Control Board 1. Defectiv e. 1. See "II.C .5. Control Board Check Procedure ." [7] All components run, but no ice is produced. a) Refr igerant 1. Undercharged. 1. Check f or leaks and recharge. 2. Air or moisture trapped. 2. Replace drier and recharge. b) Compressor 1. Defectiv e valv e. 1. Replace. c[...]

29 Prob lem P ossible Cause Remedy d) Expansion V alve 1. Bulb out of position or loose attachment. 1. Place in position. 2. Def ectiv e. 2. Replace. e) Hot Gas V alve 1. Coil winding opened. 1. Replace. 2. Plunger does not mov e. 2. Replace. 3. Wiring to hot gas valv e. 3. Check f or loose connection or open, and replace. f) Ice Cube Guide 1. Out [...]

30 e) Other Prob lem P ossible Cause Remedy [1] Icemaker will not stop when bin is filled with ice. a) Bin Control See "II.C .4. Bin Control T roubleshooting." b) Control Board 1. Defectiv e. 1. See "II.C .5. Control Board Check Procedure ." [2] Abnormal noise. a) Pump Motor 1. Bear ings worn out. 1. Replace b) F an Motor 1. Be[...]

31 Prob lem P ossible Cause Remedy 4. Wir ing to gear motor . 4. Check f or loose connection or open circuit, and replace wiring as needed. 5. Defectiv e capacitor . 5. Replace. 6. Agitator rotates in re v erse direction. 6. Check leads and re verse the connections. e) Solenoid 1. Solenoid winding open. 1. Replace 2. Wir ing to solenoid. 2. Check f[...]

32 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 prev ent moisture from enter ing the system when replacing [...]

33 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[...]

34 4) Remov e the ter minal cov er on the compressor , and disconnect the compressor wiring. 5) Remov e the discharge and suction pipes using brazing equipment. 6) Remov e the hold-down bolts, w ashers and r ubber grommets . 7) Remov e the compressor . Unpack the ne w compressor package. 8) Attach the rubber grommets of the prior compressor . 9) Pl[...]

35 E. Remov al and Replacement of Expansion V alve IMPOR T ANT Sometimes moisture in the refrigeration circuit e xceeds the drier capacity and freezes up at the e xpansion valv e. Alwa ys install a ne w drier ev 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[...]

36 1) T urn off the power supply . 2) Remov e the panels. Be sure to disconnect the dispense switch connector from the control bo x when remo ving the front panel. 3) Recov er the refr igerant and store it in an appro v ed container . 4) Remov e the screw and the solenoid. 5) Disconnect the hot gas v alv e using brazing equipment. 6) Install the ne[...]

37 6) Remov e the pop r iv ets securing the ev aporator , then lift out the e v aporator . 7) Install the new e v aporator . 8) Install the new drier . 9) Check f or leaks using nitrogen gas (140 PSIG) and soap bub b les. 10) Ev acuate the system, and charge it with refrigerant. See the nameplate f or the required refrigerant charge. 11) Replace th[...]

38 I. Remov al and Replacement of Thermistor IMPOR T ANT 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 or equiv alent. 3. Alwa ys use a recommended f oam insulation (non-absorbent typ[...]

39 3) Disconnect the f an motor wiring har ness from the back of the control bo x. Remov e the f our bolts securing the f an motor assembly to the floor of the machine , then remove the assembly . 4) Remov e the fan motor from the f an motor brac k et. 5) Remov e the fan b lade from the old fan motor and attach it to the ne w fan motor . 6) Instal[...]

40 7) Install the new pump , and replace the remov ed par ts in the rev erse order of which they were remo v ed. 8) T urn on the power supply , and chec k f or leaks. 9) Replace the panels in their correct positions. M. Remov al and Replacement of Spray T ubes 1) T urn off the power supply . 2) Remov e the outer panels and the ev aporator insulatio[...]

41 10) Install the new gear motor , assembling the remo v ed par ts in the re v erse order of the abov e procedure. Note: • When weight (2.2 Ib) is applied to the chain at the center , the displacement must be 0.31 to 0.51". • Lubricant (Class SAE 20) must be applied to the chain using a cloth. 11) Replace the panels in their correct posit[...]

42 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. Cleaning Instructions T o clean the machine , perf or m the cleaning and sanitizing procedures for the icemak er and bin in the order in which they appear bel[...]

43 15) T urn off the power supply after 30 min utes. 16) Remov e the front panel. 17) Mov e the ser vice switch to the DRAIN position. 18) Replace the front panel in its correct position. 19) T urn on the power supply f or 2 minutes. 20) T urn off the power supply . 21) Remov e the front panel. 22) Mov e the control switch to the ICE position. 23) [...]

44 10) T urn on the power supply f or 2 minutes. 11) T urn off the power supply . 12) Remov e the front panel. 13) Repeat steps 22 through 36 in "Cleaning Procedure – Icemaker" tw o times to rinse thoroughly . 14) Mov e the control switch to the ICE position, then proceed to "3. Cleaning Procedure – Bin". 3. Cleaning Procedu[...]

45 B. Maintenance Instructions 1. Exterior Panels T o k eep the exterior clean, wipe occasionally with a clean and soft cloth. Use a damp cloth containing a neutral cleaner to wipe off oil or dir t buildup . 2. Air Filters The plastic mesh air filters (located behind the louv ers on either side of the unit) remov e dir t and dust from the air , an[...]