Summary of Contents for Mitsubishi Electric MVZ Series
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SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS 2015 SERVICE MANUAL Series MVZ Model name Model name <Indoor unit> <Indoor unit> MVZ-A12AA4 MVZ-A18AA4 MVZ-A24AA4 MVZ-A30AA4 MVZ-A36AA4 INDOOR UNIT...
SAFETY PRECAUTION 1-1. ALWAYS OBSERVE FOR SAFETY Before obtaining access to terminal, all supply circuits must be disconnected. 1-2. CAUTIONS RELATED TO NEW REFRIGERANT Cautions for units utilising refrigerant R410A Use new refrigerant pipes. Do not use refrigerant other than R410A. In case of using the existing pipes for R22, be careful with If other refrigerant (R22 etc.) is used, chlorine in refrige- the followings.
Unit Gravimeter [3] Service tools Use the below service tools as exclusive tools for R410A refrigerant. Tool name Specifications Gauge manifold · Only for R410A · Use the existing fitting specifications. (UNF1/2) · Use high-tension side pressure of 5.3MPa·G or over. Charge hose ·...
HEATER CONTROL 9-1. CONTROL SPECIFICATIONS AND FUNCTION SETTING Table 1 shows how the field-installed heater is controlled. Select the desired pattern in the table below, and set the Function on the indoor units as shown in Table 1. Table.1 [Function table] Select unit numbers 01 to 03 or all units (AL [wired remote controller] / 07 [IR wireless remote controller]) Setting ode (function) No.
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9-2. FAN CONTROL By setting the Mode No. 23 in the Function Table in section 9-1, the following patterns of fan control will become possible. Fan control patterns Fan in defrost Fan(All modes other Factory CN4Y for FAN control Mode(function) (PAC-YU25HT) No.23(123) than defrost)
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(3) Locally procured wiring A basic connection method is shown below. Indoor unit Remote control board Relay circuit control board Adapter CN24-1 or CN24-2 White Electric Heater or panel heater Preparations in the field Maximum cable length is 10 m (32ft) For relay X use the specifications given below Operation coil Rated voltage: 12VDC Power consumption: 0.9W or less...
HUMIDIFIER CONTROL 10-1. CONTROL SPECIFICATIONS The below table shows how the field installed humidifier and fan speed is controlled. Mode (function) No. Humidistat Condition (no defrost/no error) CN25 output Fan speed output Wired remote controller (RF thermostat) 13 (113) 16 (116) CNF input Heat operation &...
TROUBLESHOOTING 12-1. CAUTIONS ON TROUBLESHOOTING (1) Before troubleshooting, check the followings: 1 Check the power supply voltage. 2 Check the indoor/outdoor connecting wire for mis-wiring. (2) Take care the followings during servicing. 1 Before servicing the air conditioner, be sure to turn off the remote controller first to stop the main unit, and then turn off the breaker.
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12-2. SELF-CHECK FUNCTION • Refer to the installation manual that comes with each remote controller for details. • RF thermostat is not established. [Output pattern A] Errors detected by indoor unit Wired remote controller IR wireless remote controller RF thermostat Symptom Remark Beeper sounds/OPERATION...
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For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table. LED 1 (power for microcomputer) Indicates whether control power is supplied. Make sure that this LED is always lit. LED 2 (power for remote controller) Indicates whether power is supplied to the remote controller.
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Note: Refer to the manual of outdoor unit for the details of display 12-3. SELF-DIAGNOSIS ACTION TABLE such as F, U, and other E. Abnormal point and detection method Countermeasure Error Code Cause 1 Defective thermistor 1–3 Check resistance value of thermistor. Room temperature thermistor (TH1) characteristics...
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Abnormal point and detection method Countermeasure Error Code Cause Freezing/overheating protection is (Cooling or drying mode) (Cooling or drying mode) 1 Clogged filter (reduced airflow) 1 Check clogging of the filter. working 1 Freezing protection (Cooling mode) 2 Short cycle of air path 2 Remove shields.
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Abnormal point and detection method Countermeasure Error Code Cause 1 Defective thermistor 1–3 Check resistance value of thermistor. Abnormality of pipe temperature ther- mistor / Condenser-Evaporator (TH5) characteristics For characteristics, refer to (P1) above. 2 Check contact failure of connector (CN44) 1 The unit is in three-minute resume pro- 2 Contact failure of connector on the indoor controller board.
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Abnormal point and detection method Countermeasure Error Code Cause ∗ Check LED display on the outdoor control cir- 1 Contact failure, short circuit or, Indoor/outdoor unit communication error (Signal receiving error) cuit board. (Connect A-control service tool, mis-wiring (converse wiring) of 1 Abnormal if indoor controller board PAC-SK52ST.) indoor/outdoor unit connecting...
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12-4. TROUBLESHOOTING BY INFERIOR PHENOMENA Note: Refer to the manual of outdoor unit for the detail of remote controller. Phenomena Cause Countermeasure (1)LED2 on indoor controller board • When LED1 on indoor controller board is also off. 1 Power supply of rated voltage is not supplied to out- 1 Check the voltage of outdoor power is off.
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12-5. TEST POINT DIAGRAM 12-5-1. Power supply board MVZ-A12AA4 MVZ-A18AA4 MVZ-A24AA4 MVZ-A30AA4 MVZ-A36AA4 Power supply voltage (208 - 230VAC) CNMF Fan motor output 1 - 4: 310 - 340 VDC 5 - 4: 15 VDC 6 - 4: 0 - 6.5 VDC 7 - 4: Stop 0 or 15 VDC Run 7.5 VDC (0 - 15 pulse)
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12-5-2. Indoor controller board MVZ-A12AA4 Emergency operation MVZ-A18AA4 MVZ-A24AA4 Model selection MVZ-A30AA4 Capacity setting MVZ-A36AA4 CN105 Radio frequency interface CN105 CN22 CN32 Remote start/stop adapter CN22 For MA remote controller cable con- CNXA2 nection (10 - 13 VDC) CN25 CNXC2 CN51 Centralized control CNER CNXB2...
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12-6. TROUBLE CRITERION OF MAIN PARTS MVZ-A12AA4 MVZ-A18AA4 MVZ-A24AA4 MVZ-A30AA4 MVZ-A36AA4 Part name Check method and criterion Room temperature Measure the resistance with a tester. thermistor (Part temperature 10°C (50°F) ~ 30°C (86°F)) (TH1) Normal Abnormal Pipe temperature 4.3kΩ~9.6kΩ Opened or short-circuited thermistor/liquid (TH2) Condenser/evaporator...
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12-8. DC FAN MOTOR (FAN MOTOR/INDOOR CONTROLLER BOARD) Check method of DC fan motor (fan motor/indoor controller circuit board) Notes · High voltage is applied to the connecter (CNMF) for the fan motor. Give attention to the service. · Do not pull out the connector (CNMF) for the motor with the power supply on. (It causes trouble of the indoor controller circuit board and fan motor.) Self check...
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12-9. FUNCTIONS OF DIP SWITCH AND JUMPER WIRE Each function is controlled by the dip switch and the jumper wire on control p.c. board. SW1 and SW2 are equipped only for service parts. Model setting and capacity setting are memorized in the nonvolatile memory of the control p.c. board of the unit.
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DISASSEMBLY PROCEDURE 1. Control box Exercise caution when removing heavy parts. 1. Remove the Electric panel (2 screws) 2. Remove the Control box cover (1 screw) Fig. 1 Fig. 2...
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2. Thermistor (Return Air) Exercise caution when removing heavy parts. 1. Remove the Filter panel (2 thumbscrews). 2. Remove the Blower panel (2 screws). Fig. 3 3. Remove the cover over the Return Air thermistor box and unplug the thermistor. 4.
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3. Coil Assembly Exercise caution when removing heavy parts. 1. Remove the Electrical, Blower and Filter panel indicated in sections 1 and 2. 2. Remove the Coil panel by removing all of the screws securing it to the (3) smaller panels for refrigerant and drain lines.
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5. Remove the plate covering the coil assembly to access the thermistors. Fig. 9 6. Remove lower and side drain pan. Fig. 10...
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4. Blower/Fan Assembly Exercise caution when removing heavy parts. 1. Remove the Blower and Filter panel (along with filter if installed) indicated in section 2. 2. Remove the (1 or 2) brackets that secure the coil assembly. Fig. 11 3. Remove the door that covers the small enclosure attached to the fan assembly (Fig.12).
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http://Global.MitsubishiElectric.com New publication effective Feb. 2015 Specifications subject to change without notice HWE1407A...