Page 1
SERVICE MANUAL OFFICE PRO W20 SERIAL NUMBER FROM April 2011 (0411) TO PRESENT DocID: 00G00074E...
Page 2
All rights reserved. This book may not be reproduced or copied, in whole or in part, without the written permission of the publisher. DENSO SALES CALIFORNIA, INC. reserves the right to make changes without prior notice. MovinCool®, Office Pro® and SpotCool® are registered trademarks of DENSO Corporation.
Operation Section 1. PRECAUTIONS FOR SAFETY 1.1 Foreword • This manual has been published to service the MovinCool Office Pro W20. Please use this service manual only when servicing this unit. 1.2 Definition of Terms Describes precautions that should be observed in order to prevent injury to WARNING the user during installation or unit operation.
Operation Section 2.2 Technical Specifications ITEM SPECIFICATIONS Electronic Features Operation Digital Programmable Electrical Characteristics Voltage Requirement Single-Phase, 115 V, 60 Hz Operating Max. 127 V Voltage Range Min. 104 V Starting Current 65 A Recommended Fuse Size 15 A 11.7 A 65 A Cooling Capacity and Power Consumption Air: 80 °F (27 °C), 50 %RH...
Page 9
Operation Section ITEM SPECIFICATIONS Weight 178 lb (81 kg) Shipping 209 lb (95 kg) Drain Tank Capacity 5.0 gal (19 L) Operating Condition Range Inlet Air Max. 95 °F (35 °C), 60 %RH Temperature Min. 65 °F (18 °C), 50 %RH Max.
Operation Section 2.3 Characteristics • All characteristic values are within 10 % tolerance. ± • EWT shown in the graphs is an abbreviation of “Entering Water Temperature”. (1) Cooling capacity curve Wet Bulb Temp. °F (°C) (10) (13) (16) (18) (21) (24) (27)
Page 12
Operation Section (2) Power consumption curve 2.4 3.6 4.8 6.0 7.2 (13) (18) (24) (29) (35) Entering Water Temp. °F (°C) Water Flow (GPM) ILL00224-00 How to read the power consumption curve Example: EWT: 85 °F (29 °C), Water flow: 7.2 GPM Power Consumption: 1.22 kW Reference Value...
Page 13
Operation Section (3) Current consumption curve 2.4 3.6 4.8 6.0 7.2 (13) (18) (24) (29) (35) Entering Water Temp. °F (°C) Water Flow (GPM) ILL00226-00 How to read the current consumption curve Example: EWT: 85 °F (29 °C), Water flow: 7.2 GPM Current Consumption: 1.12 A Reference Value...
Operation Section 3. CONSTRUCTION 3.1 Exterior Components Control Panel Water Outlet Evaporator Air 1/2" NPT Female Connector (With Plug) Outlet Grill Evaporator Air Inlet Panel Water Inlet Drain Tank Cover Caster 1/2" NPT Female (With Plug) Service Panel Power Cord ILL00133-00...
Operation Section 3.2 Internal Structure Fan Motor Evaporator Water Regulating Valve Capillary Tube Service Panel Drain Pan Condenser Control Box Drain Tank Drain Switch Compressor ILL00134-00 3.3 Basic Construction • The unit is compact in construction because the condenser and the evaporator are enclosed in one unit.
Operation Section 3.4 Air Flow • Air taken in from the front face is cooled by the evaporator and then blown through the cool air vent. The air inlet is equipped with a filter. Cool Air Out Evaporator Air In ILL00135-00 3.5 Compressor and Fan •...
Operation Section 4. REFRIGERATION SYSTEM 4.1 Refrigeration System Construction The component parts of the refrigeration system include the following: • Compressor, Evaporator, Condenser, Capillary tube, High pressure switch These parts are all connected by copper tubing. All the connections have been brazed. Condenser Water Regulating Valve Capillary Tube...
Operation Section 4.2 Compressor • The compressor used for the unit is hermetically sealed. The compressor and the compressor motor are in one casing. (1) Compressor construction •The construction of a rotary type compressor is divided into two mechanisms; the drive mechanism (compressor motor), and the compression mechanism (compressor).
Page 20
Operation Section (2) Basic compressor operation •The roller (compression mechanism) is set Discharge Hole eccentrically with a certain distance given from Spring Discharge the axis of the center of the cylinder. A spring Suction Valve Hole loaded blade is mounted on the cylinder. The Blade roller turns to compress the refrigerant in the space between the cylinder and eccentrically...
Page 21
Operation Section (3) Operation 1) Start of compression 1) The cylinder is filled with low pressure gas. Discharge Blade Valve 2) Since pressure in the discharge chamber is higher than in the cylinder, the discharge valve is kept closed. Roller I001676 2) Suction and compression 1) The pressure in the cylinder increases...
Operation Section (4) Compressor lubrication •The lubrication system is comprised of a hollow shaft, an oil scraper mounted at the end face, hollow shaft, a shaft journal (shaft bearing), Rotor and the lubrication groove for the shaft journal. The lubrication groove is wider than the oil Hollow Shaft hole.
Operation Section 4.5 Evaporator • The evaporator is a heat exchanger covered with plate fins. Heat is removed from the air being pulled across the evaporator by the centrifugal fan and the resulting cool air is expelled through the cool air vent. 4.6 Accumulator •The accumulator is mounted on the suction gas From Evaporator...
Operation Section 5. WATER SYSTEM 5.1 Water Regulating Valve • This unit is equipped with a water regulating Adjusting Bolt valve to operate within wide water temperature Water Regulating Valve range. This water regulating valve automatically controls the water flow rate to stabilize the refrigeration system and it has an adjusting bolt to adjust the valve opening temperature.
Operation Section 5.3 Adjustment of Water Regulating Valve Setting 1) Stop the unit and unplug the power cord. Then shut off the water supply. 2) Remove five (5) screws from the service panel on the rear side of the unit. Screws (5) 3) Remove thirteen (13) screws from the rear panel.
Page 26
Operation Section 7) Write the value setting with a permanent marker on the adjustment record table on the inside panel of the unit. < NOTE > Recording the value setting is very important for reference when making future adjustments. Valve Setting Guide Table Setting Direction of Valve Rotation Number of Rotation Valve Opening Temperature Minimum Water Temperature Clockwise...
Operation Section 6. ELECTRICAL SYSTEM 6.1 Circuit Diagram and Control Box φ AC 115 V 1 60 Hz HPRS Jumper Line J101 J102 J103 J104 J106 J201 IOLF J108 J105 Attachment Plug I O L F Inner Overload Relay of Fan Motor T B 1 Terminal Block O L C...
Operation Section 6.2 Basic Operation of Electrical Circuit • There are two basic components used to control the operation of electrical system: - Control panel assembly - Control box • The control panel assembly contains the control panel, control board (with inputs for the freeze and room temperature thermistors), drain switch and a microprocessor.
Operation Section 6.3 Control Box (1) Capacitors • The capacitors are used to temporarily boost the power output available to the fan motor and the compressor at start-up. • The specifications of each capacitor are listed below: Capacitor Application Voltage Rating Capacitance Fan Motor 370 VAC...
Page 30
Operation Section (2) Relay board • The relay board receives signals and outputs <Dip Switch> from the control board that contains a Dip Switch microprocessor. The relay board contains the Temperature Scale compressor, fan on, and fan mode (speed) Display Switch (°C ⇔...
Operation Section 6.4 Fan Motor • The fan motor is a single phase, induction type two-speed motor. The motor rotates the fan on the evaporator side. Specifications: Rated Voltage 115 V, 60 Hz CF1 (White) CF2 (Brown) Rated Output High: 112 W, Low: 87 W Ground J5 Low (Red) (Green/Yellow)
Operation Section 6.6 Compressor Overload Relay • An external compressor overload relay is used Bimetal to protect the compressor motor. This relay is mounted within the connector housing that Points attaches to the top of the compressor. The relay interrupts the flow of current when there is an overload condition and, high temperature Terminal builds up in the compressor.
Operation Section 7. CONNECTION AND SETTING 7.1 Warning Signal Connection (Output Signal Terminal L+ and L-) • The controller is equipped with a warning signal output relay type (Form C, normal open dry contact) which can be used to monitor the failure conditions. Relay contactor is closed when any of the following conditions has occurred: - Tank Full - Temperature sensor fails...
Operation Section 7.2 Fire Alarm Control Panel Connection (Input Signal Terminal E+ and E-) • The controller is equipped with a normal open input signal, which can be connected directly from the fire alarm control panel. When receiving the signal from the fire alarm control panel, the unit turns off and does not turn back until it has been reset.
Operation Section 8. OPERATION 8.1 Automatic Restart after Power Interruption (Automatic Recovery Function) • The program within the microprocessor of this unit contains a feature that automatically restarts the unit after power is lost and then regained. The unit also has memory in order to return itself back to the operating mode (either manual or preset program) it was in prior to the loss of power.
Operation Section 8.5 Fan Mode Control Switch • The fan motor operation is controlled by relays on the relay board through a microprocessor in the control panel assembly. The fan program in the microprocessor can be changed by a DIP switch on the left side of the relay board located in the control box.
Operation Section 8.6 Drain Switch • This unit is equipped with a drain tank switch. When the drain tank accumulates approximately 4.0 gal (15 L) of condensate (water) in the drain tank, the drain tank switch sends a signal to the microprocessor.
Operation Section (1) How to re-start the unit • If the LCD indicates “PROGRAM ON”, press the COOL ON/OFF button to continue running the program. If the LCD indicates “PROGRAM ON” continuously (program activated), no further steps are necessary. If no program exists or the program was deactivated, press the FAN MODE button or the COOL ON/OFF button.
Repair Section 9. TROUBLESHOOTING 9.1 Troubleshooting • Before troubleshooting the system, the following inspection should be performed. WARNING • Disconnect power prior to servicing the relay board. • Failure to follow this warning may lead to electrical shock. (1) Inspection of power source voltage •...
Repair Section 9.2 Self-Diagnostic Codes • Self-diagnostic codes are displayed on the control board under the following conditions. Refer to the troubleshooting chart on page 44 to 46 for the remedies. LCD Display Description Condition Drain tank is full When the drain tank is filled with drain water. (“TANK FL”...
Page 41
Repair Section LCD Display Description Condition Press HI/LO and buttons simultaneously for 3 seconds to check LCD Show LCD and LED MO TU WE TH FR SA SU all on mode segments and LED display. START PROGRAM STOP After 5 seconds, display goes back to normal operation mode. CLOCK LOCKED SET TEMP...
Repair Section 9.3 Troubleshooting Chart • To accurately troubleshoot the problem, it is important to carefully confirm the nature of the problem. Common problems are: - Insufficient cooling. - Unit does not operate. - Overflow of drain water. - Abnormal noise or vibrations. - Others.
Page 43
Repair Section Condition Check Area Possible Cause Remedy Insufficient Cooling 1. Usage conditions Operation near usage limits. Review the installation (high temperature). place. 2. Dirt in evaporator. Insufficient heat exchange. Clean fins. 3. Frost in refrigeration cycle. Clogging at the frost section. Replace clogged section. 4.
Page 44
Repair Section (2) Unit does not operate < NOTE > • In this case, there is a possibility of safety device activating due to the clogged air filter. So make sure to first clean the air filter and then start up again to confirm if the problem lies with the air filter. •...
Page 45
Repair Section Condition Check Area Possible Cause Remedy Unit does not operate. 3. Display code “RT”. Loose room thermistor Reconnect the room connection. thermistor and check the connection. RESET the controller Defective room thermistor Replace room thermistor. (short or open). 4.
Page 46
Repair Section Condition Check Area Possible Cause Remedy Unit does not operate. 6. Display code “ALRM”. Signal is input from the fire Check the fire alarm system Control alarm. and confirm there is no signal Control Panel input to the unit, then RESET panel display the controller...
Page 47
Repair Section (3) Overflow of water from the unit Condition Check Area Possible Cause Remedy 1. Drain pan. Cracks in drain pan. Check and replace. 2. Water level in drain pan. Clogged drain hose. Check and repair. 3. Drain hole. Reversed air flow from drain Insert a trap on discharge hole.
Repair Section 9.4 Basic Inspection • Perform the following inspection before disassembly. (1) Inspection of plate fins • To inspect the plate fins of the evaporator, open the front panel door, and inspect the plate fins for any dirt, dust, lint, or debris that may have caused insufficient cooling performance of the unit.
Repair Section 9.5 Inspection of Capacitor (for Fan Motor and Compressor) (1) Ohmmeter method • Set the ohm-meter to the 10M range. Place the two probes against the two terminals of the capacitor. At first, the ohm-meter should indicate small value, then the reading should gradually increase towards...
Repair Section 9.7 Inspection of Fan Motor • Measure resistance across the terminals of the fan motor. (All terminals must be disconnected from the unit.) • Between terminals (at 77 °F (25 °C)) - J6-CF1 Approx. 10.6 ohm - J6-CF2 Approx. 50.2 ohm CF1 (White) - J5-J6 Approx.
Repair Section 9.11 Inspection of Refrigeration System • In most cases, the probable cause for insufficient cooling is a clog in the system, a leakage or an incorrect amount of refrigerant. In such cases, inspect the system according to the following procedure.
Repair Section 9.12 Inspection of Water System • In most cases, the cause for insufficient cooling is a clog in the system, a leakage, or an incorrect amount of water in the system. In such cases, inspect the system according to the following procedure.
Page 53
Repair Section 4) Remove thirteen (13) screws from the rear panel. Screws (3) Screws (7) Screws (3) ILL00148-00 5) Open the faucet handle to supply water. 6) Insert screwdrivers under both sides of the valve spring guide of the water regulating valve and lift upwards to flush.
Repair Section 10. DISASSEMBLY 10.1 Parts Construction Control Panel Upper Front Panel Right Handle Upper Panel Right Panel Air Outlet Grill Front Panel Filter Assy Room Thermistor Freeze Protection Thermistor Filter Element Drain Tank Panel Assy Drain Pan Assy Left Handle Drain Tank Rear Panel Service Panel...
Repair Section 10.2 Disassembly 1) Remove drain tank. I002203 2) Remove four (4) screws from upper front panel. Screw (1) Screw (1) Screws (2) ILL00145-00 3) Slide upper front panel forward and remove. ILL00146-00 4) Louver can be removed from upper front panel by unsnapping the lock tap and removing the louver Pivots from its pivots.
Page 56
Repair Section 5) Remove five (5) screws from service panel. Screws (5) ILL00147-00 6) Remove thirteen (13) screws from rear panel. Screws (3) Screws (7) Screws (3) ILL00148-00 7) Remove eight (8) screws from upper panel. Screws (2) Screws (3) Screws (3) ILL00149-00 8) Remove seven (7) screws from left panel.
Page 57
Repair Section 9) Remove twelve (12) screws from right panel. Screws (3) Screws (6) Screws (3) ILL00151-00...
Repair Section 10.3 Removal of Evaporator Fan Assembly Control Panel Stay Air Deflector Evaporator Fan Casing Motor Stay Evaporator Fan Fan Motor Center Panel ILL00154-00...
Page 59
Repair Section 1) Remove four (4) nuts as shown. Then remove the motor stay together with the fan motor. Nut (1) Nut (1) Nut (1) Nut (1) ILL00155-00 2) Loosen the set screw using a hex key. Then Set Screw Nuts (2) remove the fan motor by loosening four (4) nuts.
Repair Section 10.4 Removal of Electrical Components WARNING • Disconnect power prior to servicing the relay board. • Failure to follow this warning may lead to electrical shock. (1) Control box 1) Remove five (5) screws from service panel. (See page 56.) 2) Remove electrical parts.
Page 61
Repair Section (2) Relay board 1) Remove five (5) screws from service panel. (See page 56.) 2) Disconnect seven (7) connectors, and remove five (5) screws from relay board. Temperature Scale Display Switch Dip Switch To Control Board(10 pin) Fan Mode Control Switch To Condensate Pump(2 pin) To Compressor (Black) Power (#T1) OnTerminal Block...
Page 62
Repair Section 3) Disconnect the following connectors from the control board: (A) J201 (10-pin) Wire Harness, Relay Board to Control (B) J101 (2-pin) Room Temperature Thermistor (C) J102 (2-pin with black tape) Freeze Protection Thermistor (D) J103 (2-pin) Drain Tank Switch ILL00153-00 (E) J104 (2-pin) High Pressure Switch (F) J106 (2-pin) Output signal terminal...
Page 63
Repair Section (4) Battery replacement of control board • When the power is disconnected from the unit, and control board is automatically resetting clock and program, it is time to change the battery on the control board to avoid resetting of clock and program.
Repair Section 11. REFRIGERANT AND WATER SYSTEM REPAIR 11.1 Repair of Refrigerant and Water System • In case there is a leak, obstruction, or problem in the refrigerant and water system of this unit, replace or repair the part in question. After replacing any component, all connections must be brazed except the flare connections of the water regulating valve.
Page 65
Repair Section (4) Use of dry nitrogen gas • During brazing, the inside of the pipe undergoes an oxidative reaction due to the brazing flame. Introduce dry nitrogen gas (0.27 gal/min (1 L/min); adjust with the flow regulator) through the pinch-off tube of the refrigerant.
Repair Section 11.2 Removal of Refrigeration and Water System Components WARNING • Before replacing any refrigeration and water system component, recover the refrigerant using standard recovery procedures and drain the water from the unit. • When recovering the refrigerant, use the pinch-off tubes at the low pressure side (tube 1) and high pressure side (tube 2) as shown in the figure below.
Page 67
Repair Section (1) Removal of water cooled condenser 1) Disconnect four brazing points (A ~ D) as shown. When brazing, cover the area E with a wet cloth to prevent damage. ILL00189-00 2) Remove two (2) nuts from the bracket. Then Nuts (2) remove the water cooled condenser.
Page 68
Repair Section (2) Removal of water regulating valve 1) Disconnect a brazing point as shown. ILL00192-00 2) Remove two (2) flare nuts. Then remove the water pipes. Flare Nuts (2) ILL00193-00 3) Remove four (4) screws and two (2) brackets. Then remove the water regulating valve.
Repair Section 11.3 Charging the System with R-410A Refrigerant • Always ensure that the refrigeration system has been properly evacuated before charging with the specified amount of R-410A. • Equipment is for R-410A only. • Liquid charge (no gas charge). •...
Page 70
Repair Section (1) Connection of gauge manifold 1) Properly remove the crushed end of the pinch-off tubes at the high pressure side and the low Charging Hose Side pressure side of the refrigerant cycle with a pipe Refrigerant cutter. Cycle Side 2) Fit the process tube fitting to the pinch-off tube on both sides.
Page 71
Repair Section (3) Checking vacuum 1) Leave the high pressure valve and the low Valve Setting pressure valve of the gauge manifold closed for 5 Closed Closed minutes or more, and confirm that the gauge Pressure Gauge pointer does not return to zero. 2) If the gauge pointer returns gradually to zero Return there is a leak somewhere in the system (this...
Page 72
Repair Section (4) Checking gas leak 1) Remove the charging hose (green) from the Valve Setting vacuum pump, and connect the hose to the Closed Closed Air Purging refrigerant cylinder (R-410A). Open The Valve 2) Loosen the nut on the gauge manifold side of the of Refrigerant Cylinder charging hose (green).
Page 73
Repair Section (5) Evacuation (repeat) 1) Close the valve of the refrigerant cylinder. Then Valve Setting remove the charging hose (green) from the Gauge Closed Open Closed Closed 30 inHg (100 kPa) or larger refrigerant cylinder, and connect it to the Low Pressure High Pressure Gauge refrigerant recovery machine.
Repair Section 11.4 Refrigerant Charging Work (1) Refrigerant charging 1) Remove the charging hose (green) from the Valve Setting vacuum pump, and connect it to the refrigerant Closed Closed Air Purging cylinder (R-410A). Open The Valve 2) Loosen the nut on the gauge manifold side of the of Refrigerant Cylinder charging hose (green).
Page 75
Repair Section (2) Removal of gauge manifold 1) Crimp the pinch-off tube with a pinch-off tool. Pinch-Off Tool 2) Remove the gauge manifold and the process To Gauge Manifold Side Pinch-Off Tube tube fitting. Crush the end of the pinch-off tube. 3) Braze the end of the pinch-off tube.
Repair Section 12. REASSEMBLY 12.1 Reassembly of Unit • Reassemble the unit in the reverse order of removal. Described below are the parts that require special care in reassembling the unit. Perform all wiring or rewiring as referenced in the wiring diagram.
Repair Section 12.5 Perform the Inspection • Perform the inspection of cooling performance and check for abnormal noise or abnormal vibration. 12.6 Caster Maintenance • Lubricate bearings in caster as needed with standard bearing grease using the zerk fitting. < NOTE > Casters should roll and swivel freely.
Page 78
DENSO SALES CALIFORNIA, INC. Long Beach, CA 90810 www.movincool.com P/N: SV0036-00 First Issue: April 2011...
Need help?
Do you have a question about the OFFICE PRO W20 and is the answer not in the manual?
Questions and answers