FILE NO. SVM-16051-1 SERVICE MANUAL AIR-CONDITIONER MULTI TYPE INDOOR UNIT Concealed Duct High Static Pressure Type < > MMD-AP0726HP-UL MMD-AP0966HP-UL R410A Revised on February, 201 7...
SAFETY CAUTION The important contents concerned to the safety are described on the product itself and on this Service Manual. Please read this Service Manual after understanding the described items thoroughly in the following contents (Indications/Illustrated marks), and keep them. The manufacturer shall not assume any liability for the damage caused by not observing the description of this manual.
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WARNING Before troubleshooting or repair work, check the ground wire is connected to the ground terminals of the main unit, otherwise an electric shock is caused when a leak occurs. If the ground wire is not correctly connected, contact an electric engineer for rework. Check ground wires.
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WARNING After the work has finished, be sure to use an insulation tester set (500V Megger) to check the resistance is 2MΩ or more between the charge section and the non-charge metal section (Ground position). If the resistance value is low, a disaster such as a leak or electric shock is caused at user’s Insulator check side.
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• Refrigerant (R410A) This air conditioner adopts a HFC type refrigerant (R410A) which does not deplete the ozone layer. 1. Safety Caution Concerned to Refrigerant (R410A) The pressure of R410A is high 1.6 times of that of the former refrigerant (R22). Accompanied with change of refrigerant, the refrigerating oil has been also changed.
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4. Tools 1. Required Tools for R410A Mixing of different types of oil may cause a trouble such as generation of sludge, clogging of capillary, etc. Accordingly, the tools to be used are classified into the following three types. 1) Tools exclusive for R410A (Those which cannot be used for conventional refrigerant (R22)) 2) Tools exclusive for R410A, but can be also used for conventional refrigerant (R22) 3) Tools commonly used for R410A and for conventional refrigerant (R22) The table below shows the tools exclusive for R410A and their interchangeability.
4. WIRING DIAGRAMS Concealed Duct High Static Pressure Type Wiring Diagram Indi cati RED : Red WHI : White YEL : Yellow BLU : Blue BLK : Black BRW : Brown -TOS1217A t° t° t° t° FLEX Application control 1 2 3 4 5 1 2 3 4 5 P.C.
5. PARTS RATING Model MMD-AP 0726HP* 0966HP* KF-340W1000-1 Fan motor EFM-MD12TF-3 Pulse motor (motor only) EFM-A0YGTF-2 Pulse motor valve (motor&valve) Lead wire length:8.6" (218mm) TA sensor ∅0.16"(4mm) size lead wire length:39.4" (1000mm) Vinyl tube (Blue) TC1 sensor ∅0.24"(6mm) size lead wire length:39.4" (1000mm) Vinyl tube (Black) TC2 sensor ∅0.24"(6mm) size lead wire length:39.4"...
6. REFRIGERANT CYCLE DIAGRAM Indoor unit Liquid side Gas side Strainer Capillary tube Heat exchanger at indoor side Pulse Motor Valve (PMV) Strainer Sensor (TCJ) Sensor (TC2) Sensor (TC1) Sensor Fan motor (TA) Explanation of functional parts in indoor unit Functional part name Functional outline Pulse Motor Valve...
7. CONTROL OUTLINE Indoor unit Control specifications Item Specification outline Remarks Upon power 1. Identification of outdoor unit supply reset When the power supply is reset, the outdoor unit is identified, and control is redirected according to the identification result. 2.
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Item Specification outline Remarks 1. The fan operates in one of the four speed modes of “HIGH (HH)”, “MED Fan speed HH > H+ > H > (H)”, “LOW (L)” and “AUTO” on the basis of a command issued via the L+ >...
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Item Specification outline Remarks 1. In heating operation, the upper limit of the fan tap is set according to the Cold air TCJ: Indoor heat discharge lower of whichever is the higher between TC2 sensor and TCJ sensor exchanger temperatures, on the one hand, and TC1 sensor temperature, on the prevention sensor other.
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Item Specification outline Remarks • Recovery operation Cooling oil While the outdoor unit is recovering cooling oil (refrigerant), the indoor normally takes (refrigerant) units perform the following control tasks: place roughly every recovery control [common for operational (cooling thermostat ON / thermostat OFF / FAN), 2 hours.
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Item Specification outline Remarks Filter sign ” displayed The indoor fan’s cumulative hours of operation are counted, and when “FILTER these exceed the prescribed value (2500H), a filter replacement signal display is sent to the remote control to display a filter sign on it. (not applicable When a filter reset signal is received from the remote control, the timer to wireless type)
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Item Specification outline Remarks 1) When the fan operation has started, positioning of the stator and the DC motor rotor are performed. (Moves slightly with tap sound) 2) The motor operates according to the command from the indoor control. Notes) •...
8. APPLIED CONTROL AND FUNCTIONS (INCLUDING CIRCUIT CONFIGURATION) 8-1. Indoor control block diagram 8-1-1. In Case of Connection of Wired (Simple) Remote Control Wired (Simple) header remote control Schedule timer (Up to 2 units) Display LCD Function setup Display driver Key switch Display LED Function setup...
8-1-2. In Case of Connection of Wireless Remote Control Indoor unit #1 (Header) (Follower) (Follower) Wireless remote control kit Indoor control P.C. Board Receiving P.C. Board (MCC-1643) DC20V Remote conrol Remote conrol communication circuit communication circuit Emergent EEPROM operation Power circuit UART commnucation TA sensor DC5V...
8-1-3. Connection of Both Wired (Simple) Remote Control and Wireless Remote Control Schedule timer Wired (Simple) header remote control Display LCD Function setup Display driver Key switch EEPROM Function setup DC5V DC5V Power Display LED Key switch circuit Remote control Secondary Power communication circuit...
8-2-2. Fan IPDU P.C. Board (MCC-1610) Power relay output CN602 CN602 CN702 UART CN504 communication between CN504 CN505 UART CN705 communication between Application Fan motor output U-phase control P.C.Board CN705 CN704 CN505 Fan motor output V-phase CN704 CN703 Fan motor output W-phase CN703 CN511 CN500...
8-3. Test operation of indoor unit Check function for operation of indoor unit (Functions at indoor unit side) This function is provided to check the operation of the indoor unit singly without communication with the remote control or the outdoor unit. This function can be used regardless of operation or stop of the system. However, if using this function for a long time, a trouble of the equipment may be caused.
8-4. Method to set indoor unit function DN code (When performing this task, be sure to use a wired remote control.) <Procedure> To be performed only when system at rest Push the buttons simultaneously and hold for at least 4 seconds. The unit No.
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Function CODE No. (DN Code) table (includes all functions needed to perform applied control on site) Item Description At shipment Filter display delay timer 0000: None 0001: 150H According to type 0002: 2500H 0003: 5000H 0004: 10000H Dirty state of filter 0000: Standard 0000: Standard 0001: High degree of dirt (Half of standard time)
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Type DN code “10” Value Type Model ∗∗∗ Concealed Duct High Static Pressure Type MMD-AP 0006 HP-UL Indoor Unit Capacity DN code “11” Value Capacity 0000* Invalid 0001 007 type 0003 009 type 0005 012 type 0007 015 type 0009 018 type 0011 024 type...
8-5. Applied control of indoor unit Control system using Remote location ON/OFF control box (TCB-IFCB-4UL) Wiring and setting • In the case of group control, the control system functions as long as it is connected to one of the indoor units (control P.C.
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Ventilating fan control from remote control [Function] • The start / stop operation can be operated from the wired remote control when air to air heat exchanger or ventilating fan is installed in the system. • The fan can be operated even if the indoor unit is not operating. •...
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Leaving-ON prevention control [Function] • This function controls the indoor units individually. It is connected with cable to the control P.C. board of the indoor unit. 2E 2E 2E 2E 2E • In a group control, it is connected with cable to the indoor unit (Control P.C. board), and the CODE No. is set to the connected indoor unit.
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Manual address setting using the remote control Procedure when setting indoor units’ addresses first under the condition that indoor wiring has been completed and outdoor wiring has not been started (manual setting using the remote control) Wiring example of 2 refrigerant lines Refrigerant line 1 Refrigerant line 2 Outdoor...
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<Line (system) address> 12 12 12 12 12 Push the TEMP. buttons repeatedly to set the CODE No. to Push the TIME buttons repeatedly to set a system address. (Match the address with the address on the interface P.C. board of the header outdoor unit in the same refrigerant line.) Push button.
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Confirming the indoor unit addresses and the position of an indoor unit using the remote control Confirming the numbers and positions of indoor units To see the indoor unit address of an indoor unit which you know the position of indoor unit. When the unit is individual (the indoor unit is paired with a wired remote control one-to-one), or it is a group-controlled one.
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To find an indoor unit’s position from its address When checking unit numbers controlled as a group TEMP. ON / OFF TIMER SET MODE TIME SAVE VENT Stop FILTER RESET TEST SWING/FIX UNIT LOUVER (Execute it while the units are stopped.) The indoor unit numbers in a group are indicated one after another.
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To check all the indoor unit addresses using an arbitrary wired remote control. (When communication wirings of 2 or more refrigerant lines are interconnected for central control) TEMP. ON / OFF TIMER SET MODE TIME SAVE VENT FILTER RESET TEST SWING/FIX UNIT LOUVER (Execute it while the units are stopped.)
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Changing the indoor unit address using a remote control To change an indoor unit address using a wired remote control. The method to change the address of an individual indoor unit (the indoor unit is paired with a wired remote control one-to-one), or an indoor unit in a group. (The method is available when the addresses have already been set automatically.) TEMP.
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To change all the indoor unit addresses using an arbitrary wired remote control. (The method is available when the addresses have already been set automatically.) (When communication wirings of 2 or more refrigerant lines are interconnected for central control) NOTE You can change the addresses of indoor units in each refrigerant line using an arbitrary wired remote control.
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TEMP. ON / OFF TIMER SET MODE TIME SAVE VENT FILTER RESET TEST SWING/FIX UNIT LOUVER Finish 5, 7 Press to finish setting Push the TIME buttons repeatedly to change the value of the indoor unit address in SET DATA. Change the value in SET DATA to that of a new address.
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Check code clearing function How to clear the check code using the wired remote control Clearing an check code of the outdoor unit Clear the currently detected outdoor unit for each refrigerant line to which the indoor unit controlled by the remote control is connected. (The indoor unit check code is not cleared.) Use the service monitoring function of the remote control.
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Monitoring function of wired remote control The following monitoring function is available if the remote control of RBC-AMT32UL is used. TEMP. ON / OFF TIMER SET MODE TIME SAVE VENT FILTER RESET TEST SWING/FIX UNIT LOUVER Content Enter the service monitoring mode using the remote control to check the sensor temperature or operation status of the remote control, indoor unit, and outdoor unit.
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< Based on the SMMS-e > CODE No. Data name Display format Unit Remote control display example Room temperature (Use to control) ×1 °C [0027] = 27 °C Room temperature (Remote control) ×1 °C Indoor suction air temperature (TA) ×1 °F Indoor coil temperature (TCJ) ×1...
8-6. Application control P.C.Board (pre-installed) Application control P.C.Board is pre-installed for Secondary Heating output and another functions. <Location of Application control P.C.Board> Connector assembly 1 Take off the screws A and B then remove the Control circuit board FAN control PC board CN505(RED) terminal block assembly.
<External digital input terminal: TB2> <External analog input terminal: TB3> The following controls can be done by inputting signals to the external digital input It is possible to change the indoor unit's operation mode (AN1), set temperature (AN2), terminal. and blower setting (AN3) by connecting a variable resistor to the analog input terminal. * When both the wired remote control and the central control are used, the most ▼...
9-2. Troubleshooting method The remote controls (main remote control and central control remote control) and the interface P.C. board of an outdoor unit are provided with an LCD display (remote control) or a 7-segment display (outdoor interface P.C. board) to display operational status. Using this self-diagnosis feature, the trouble site / trouble part may be identified in the event of a trouble by following the method described below.
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(Check code detected by main remote control) Display of receiving unit Check code Outdoor 7-segment display Indicator light block Typical trouble on site Description of check code Main remote Operation Timer Ready Sub-code control Flash Signals cannot be received from indoor unit; master remote No master remote control, ⎯...
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List of Check Codes (Outdoor Unit) (Check code detected by SMMS-e outdoor interface - typical examples) If "HELLO" is displayed on the oudoor 7-segment for 1 minute or more, turn off the power supply once and then turn on the power IPDU: Intelligent Power Drive Unit (Inverter P.C.
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Check code Display of receiving unit Outdoor 7-segment display TCC-LINK Indicator light block Typical problem site Description of problem central control or main remote Operation Timer Ready Sub-code control Flash display Outdoor suction Outdoor suction temperature sensor 01: TS1 temperature sensor (TS1,TS3) has been open/short-circuited.
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Check code Display of receiving unit Outdoor 7-segment display TCC-LINK Indicator light block Typical problem site Description of problem central control or main remote Operation Timer Ready Sub-code control Flash display A3-IPDU Fan-IPDU A3-IPDU Fan-IPDU ○ ○ ○ ○ ○ ○...
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(Check code detected by IPDU featuring in SMMS-e standard outdoor unit - typical examples) Check code Display of receiving unit Outdoor 7-segment display TCC-LINK Indicator light block Typical problem site Description of proplem central control or main remote Operation Timer Ready Sub-code Flash control...
9-3. Troubleshooting based on information displayed on remote control Using main remote control (RBC-AMT32UL) (1) Checking and testing When a trouble occurs to an air conditioner, a check code and indoor unit No. are displayed on the display window of the remote control. Check codes are only displayed while the air conditioner is in operation.
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Using indoor unit indicators (receiving unit light block) (wireless type) To identify the check code, check the 7-segment display on the header unit. To check for check codes not displayed on the 7-segment display, consult the “List of Check Codes (Indoor Unit)” in “9-2. Troubleshooting method”. : Blinking (0.5 seconds) : Lighting : Goes off...
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Cause of trouble Light block Check code Heat exchanger temperature sensor (TCJ) trouble Operation Timer Ready Heat exchanger temperature sensor (TC2) trouble Indoor unit temperature Heat exchanger temperature sensor (TC1) trouble sensor trouble Ambient temperature sensor (TA) trouble Alternate blinking Discharge temperature sensor (TF) trouble Discharge temperature sensor (TD1) trouble Discharge Operation Timer...
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Cause of trouble Light block Check code Operation Timer Ready Outdoor EEPROM trouble Synchronized blinking Other (indications not involving check code) Cause of trouble Light block Check code Operation Timer Ready – Test run in progress Synchronized blinking Operation Timer Ready Setting incompatibility –...
9-4. Check Codes Displayed on Remote Control and SMMS-e Outdoor Unit (7-Segment Display on I/F Board) and Locations to Be Checked For other types of outdoor units, refer to their own service manuals. Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations)
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code Duplicated indoor address Indoor Duplicated All stop More than one indoor unit • Check indoor addresses. are assigned same address. Check for any change unit indoor address...
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code Trouble in Indoor Stop of Periodic communication • Check remote control unit communication corresponding between indoor header and wiring.
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Check code Location Trouble detection System Outdoor 7-segment display Description Check items (locations) Main condition(s) status remote detection Check Sub-code control code IPDU All stop Communication is disrupted • Check wiring and A3-IPDU Fan-IPDU A3-IPDU Fan-IPDU communication between IPDUs (P.C. connectors involved in trouble boards) in inverter box.
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Check code Location Trouble detection Outdoor 7-segment display System Description Check items (locations) Main status condition(s) remote detection Check Sub-code control code TO sensor All stop Sensor resistance is infinity • Check connection of TO trouble or zero (open/short circuit). sensor connector.
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Check code Location Trouble detection Outdoor 7-segment display System Description Check items (locations) Main status condition(s) remote detection Check Sub-code control code Indoor Other indoor Stop of Indoor P.C. board does not • Check for defect in indoor P.C. trouble –...
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code Low oil level All stop Operating compressor <All outdoor units in protection detects continuous state of corresponding line to be low oil level for about 2 hours.
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Check code Location Trouble detection Outdoor 7-segment display System Description Check items (locations) Main status condition(s) remote detection Check Sub-code control code 01: TK1 oil circuit trouble • Check for disconnection of TK1 sensor. Oil level All stop 02: TK2 oil circuit trouble Check resistance characteristics of TK1 •...
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code Indoor Outdoor units Stop of In case of different outdoor • Check outdoor unit model. unit unit (Not corresponded to model corresponding (Check whether the...
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code Trouble in No. All stop Insufficient number of IPDUs • Check model setting of A3-IPDU Fan-IPDU A3-IPDU Fan-IPDU of IPDUs are detected when power is P.C.
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Check code Location Trouble detection System Outdoor 7-segment display Description Check items (locations) Main status condition(s) remote detection Check Sub-code control code 01: Compressor 1 side IPDU Activation of high- All stop High-pressure SW is • Check connection of high- 02: Compressor 2 side pressure SW activated.
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code Outdoor liquid All stop <During cooling operation> • Check full-close operation of outdoor PMV (1, 3, 4). backflow When system is in cooling detection trouble operation, high pressure is...
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) detection remote Check Sub-code control code Detected outdoor unit No. 4-way valve All stop Abnormal refrigerating cycle • Check for defect in main reversing trouble data is collected during body of 4-way valve.
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Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection Check Sub-code control code (Sub code: #0) Fan IPDU over current • Check fan motor. protection circuit Outdoor fan #0:Element short circuit IPDU •...
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Check codes Detected by TCC-LINK Central Control Device Check code Location Trouble detection Outdoor 7-segment display Description System status Check items (locations) Main condition(s) remote detection control Sub-code TCC-LINK TCC-LINK Continued Central control device is • Check for defect in central central control operation unable to transmit signal.
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Check code Check code name Cause [P12] Indoor fan motor trouble 1. Installation environment trouble 2. Electric parts trouble 3. Wiring trouble of fan motor connector 4. Fan motor trouble 5. Indoor P.C. board trouble Power supply ON Measure the power supply voltage and if the voltage is normal or not.
10. REPLACEMENT OF SERVICE P.C. BOARD 10-1. Indoor Circuit Design Board (MCC-1643) <Note: when replacing the P.C. board for indoor unit servicing> The nonvolatile memory (hereafter called EEPROM, IC503) on the indoor unit P .C. board before replacement includes the model specific type information and capacity codes as the factory-set value and the important setting data which have been automatically or manually set when the indoor unit is installed, such as system/ indoor/group addresses, high ceiling select setting, etc.
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[1] Setting data read out from EEPROM The setting data modified on the site, other than factory-set value, stored in the EEPROM shall be read out. TEST Step 1 Push button on the remote control simultaneously for more than 4 seconds. ∗...
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B) In case that power of the indoor units cannot be turned on individually (Case 1) a) Remove temporarily the group wire connected to the terminal blocks A and B of the exchanged indoor unit. b) After connecting the remote control wire only to the removed terminal block, turn on power of the indoor units and proceed to [3].
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Step 4 Write the on-site setting data to the EEPROM, such as address setting, etc. Perform the steps 1 and 2 above again. Step 5 Change the CODE No. (DN) to “ ” by pushing buttons for the temperature setting. (this is the setting for the filter sign lighting time.) Step 6 Check the setting data displayed at this time with the setting data put down in [1].
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Table 1 CODE No. list (Example) CODE No. (DN) Item Setting data Factory-set value Filter sign lighting time Depending on Type Filter pollution leve 0000: standard Central control address 0099: Not determined 0002: +2°C (+3.6°F) Heating suction temperature shift * Automatically selection Existence of automatic COOL/HEAT mode 0001: No auto mode cooling / heating by connected outdoor...
10-2. Fan IPDU P.C. Board (MCC-1610) Replacement steps: [Remove PCB] (1) Turn off the power supply of the indoor unit and allow at least one minute for the capacitor to discharge. Confirm that the light of the LED (D640) fades away. (2) Remove all the connectors which are connected to the FAN IPDU.
11. DETACHMENTS WARNING CAUTION Be sure to stop operation of the air conditioner before Be sure to put on gloves during working time; work and then turn off switch of the breaker. otherwise an injury will be caused by a part, etc. Part name Procedure Remarks...
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Part name Procedure Remarks 2. Attachment ② Control P.C. board 1) Mount the control P.C. board in the electrical parts MCC-1643 box as before. Be sure to wire in the electrical parts box as before. NOTE 1 Check if there is no missing or contact failure of the connectors.
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No. Part name Procedure Remarks 1. Detachment ④ Noise filter Ground screws P.C. board 1) Perform 1 of ① to remove the electrical parts box. MCC-1551 2) Remove the connector of the below No. from the P.C. board. NOTE First unlock the housing and then remove the CN04 connectors.
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Part name Procedure Remarks ⑤ Application 1.Detachment control 1) Perform 1 of ① to remove the electrical parts P.C. board box cover. 2) Take off the screws A and B then remove the terminal block assembly. 3) Remove the CN1(RED) connector from the P.C. board. NOTE First unlock the housing and then remove the connectors.
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No. Part name Procedure Remarks ⑥ PMV motor 1. Detachment 1) Perform 1 of ① to remove the electrical parts box cover. 2) Loosen the fixing screws of the inspection cover and open the inspection cover. 3) Remove the connector of the PMV motor. CN82 : PMV motor (6P,Blue) connector of PMV motor 4) As shown in the right figure, using the two spanners,...
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No. Part name Procedure Remarks 1. Detachment ⑧ Fan motor, Wires of the fan 1) Perform 1 of ① to remove the electrical parts box cover. motor 2) Remove the connectors of the wires of the fan motor CN703 from the fan control P.C. board. CN704 CN703 : Fan motor (Black wire) CN705...
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No. Part name Procedure Remarks 2. Attachment ⑧ Fan motor, Fan, 1) Screw the fan motor with the motor fixing plate. (M8 x 0.8" (20mm), 2 pcs). NOTE Fix the wiring of the motor on the electrical parts box side as right figure. 2) Attach the ground screw.
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No. Part name Procedure Remarks ⑨ Drain pan 1. Detachment Screw B Bottom plate (Drain side) 1) Remove the drain hose or drain cap and then extract the drain water accumulated in the drain pan. NOTE When removing the drain hose or drain cap, be sure to take the drain water with a bucket, etc.
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Part name Procedure Remarks Heat ⑪ exchanger Left side panel Screw A Screw E Bushing Screw B Evaporator partition (back Right side panel Screw - 90 -...
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Part name Procedure Remarks 1. Detachment ⑫ Sensor TA 1) Perform 1 of ① and 1 of 7 . 2) Remove the connector of the wires of TA sensor from TA sensor the control P.C. board. CN104 3) Pinch the lock of the TA sensor holder from the outside of the electrical parts box and push it into the inside of the electrical parts box.
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WARNINGS ON REFRIGERANT LEAKAGE Important Check of Concentration Limit The room in which the air conditioner is to be installed requires a design that in the event of NOTE 2 : refrigerant gas leaking out, its concentration will The standards for minimum room volume are as follows. not exceed a set limit.