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Si-93

Troubleshooting

Part 6

Troubleshooting

1. Troubleshooting ....................................................................................31

1.1

Error Code Indication............................................................................. 31

1.2

Overall Alarm......................................................................................... 32

1.3

Overall Malfunction................................................................................ 33

1.4

Indoor Air Thermistor Error.................................................................... 34

1.5

Outdoor Air Thermistor Error ................................................................. 35

1.6

Damper System Error (Alarm) ............................................................... 36

1.7

Damper System Error (Alarm) ............................................................... 37

1.8

Dedicated LCD Remote Controller ........................................................ 38

1.9

Data Transmission Error
(Between LCD Remote Controller and Main Unit)39

1.10 Data Transmission Error (LCD Remote Controller)............................... 40
1.11 Data Transmission Error (Between LCD Master Remote Controller and

Slave Remote Controller) ..................................................................... 41

Содержание VAM 1000EJ

Страница 1: ...Heat Recovery Ventilation Applied Models VAM 500EJ VAM 800EJ VAM1000EJ VAM2000EJ SiE 93 Service Manual ...

Страница 2: ...Si 93 Table of Contents i Heat Recovery Ventilation VAM 500EJ VAM 800EJ VAM1000EJ VAM2000EJ VAM500 1000EJ VAM2000EJ ...

Страница 3: ...ns 25 1 Circuit Operations 27 1 1 Circuit Configuration 27 1 2 Circuit Functions 28 Part 6 Troubleshooting 29 1 Troubleshooting 31 1 1 Error Code Indication 31 1 2 Overall Alarm 32 1 3 Overall Malfunction 33 1 4 Indoor Air Thermistor Error 34 1 5 Outdoor Air Thermistor Error 35 1 6 Damper System Error Alarm 36 1 7 Damper System Error Alarm 37 1 8 Dedicated LCD Remote Controller 38 1 9 Data Transmi...

Страница 4: ...47 1 18 Power Transformer 48 1 19 Damper Motor 49 Part 7 Supplementary Explanation 51 1 Supplementary Explanation 53 1 1 Field Setting Service Mode Operation 53 Part 8 Appendix 63 1 Appendix 65 1 1 Wiring Diagram 65 Index i Drawings Flow Charts v ...

Страница 5: ...Si 93 iv Table of Contents ...

Страница 6: ...d Therefore be sure to observe all the safety caution items described below About the pictograms This symbol indicates an item for which caution must be exercised The pictogram shows the item to which attention must be paid This symbol indicates a prohibited action The prohibited item or action is shown inside or near the symbol This symbol indicates an action that must be taken or an instruction ...

Страница 7: ...Introduction Si 93 vi 1 1 1 Cautions in Repair Warning ...

Страница 8: ...Si 93 Introduction vii ...

Страница 9: ...le but may nevertheless be valuable to the reader such as tips and tricks Caution Caution A caution is used when there is danger that the reader through incorrect manipulation may damage equipment loose data get an unexpected result or has to restart part of a procedure Warning Warning A warning is used when there is danger of personal injury Reference A reference guides the reader to other places...

Страница 10: ...Si 93 General Constructions 1 Part 1 General Constructions 1 General Constructions 3 1 1 Explanation 3 ...

Страница 11: ...Si 93 2 General Constructions ...

Страница 12: ...ter Long Life Filter 5 Damper 6 Switch Box 7 Maintenance Cover 8 Heat Exchange Elements 9 Name Plate 10 Air Supply Fan 11 Remote Controller Option Parts 12 Damper Motor 13 EA Exhaust Air Exhaust Air to Outdoor 14 OA Outdoor Air Fresh Air from Outdoor 15 Maintenance Space for The Air Filters Heat Exchange Elements and Switch Box 16 RA Return Air Exhaust Air from Room 17 SA Supply Air Feed Air to Ro...

Страница 13: ... Switch Box 7 Maintenance Cover 8 Heat Exchange Elements 9 Name Plate 10 Air Supply Fan 11 Remote Controller Option Parts 12 Damper Motor 13 EA Exhaust Air Exhaust Air to Outdoor 14 OA Outdoor Air Fresh Air from Outdoor 15 Maintenance Space for The Air Filters Heat Exchange Elements and Switch Box 16 RA Return Air Exhaust Air from Room 17 SA Supply AIr Feed Air to Room ...

Страница 14: ...Si 93 Operations 5 Part 2 Operation 1 Operation 7 1 1 Explanation for Systems 7 1 2 Operation with The Remote Control for Air Conditioning Operation HRV Units BRC301B61 8 ...

Страница 15: ...Si 93 6 Operation ...

Страница 16: ... VENTILATION mode The ON OFF and timer operation can not be performed using the HRV remote controllers The indication of centralized control appears on the display Other operations can be performed using the HRV remote controllers Starting and stopping operations of the indoor unit and the HRV unit can be performed using the indoor remote controllers Centralized System When the HRV remote controll...

Страница 17: ...igh mode FRESH UP Low FRESH UP mode FRESH UP High FRESH UP mode Remote Controller for HRV BRC301B61 For Freshup operation When this indication does not show The volume of outdoor air supplied into the room and that of the room air exhausted outdoors is equivalent For Freshup operation If it is set to Fresh up air supply The volume of outdoor air supplied into the room is larger than that of room a...

Страница 18: ...the office hours During this period the cooling or heating load is reduced to bring the room temperature to the set temperature in a short time 7 Indication of centralized control When a remote controller for air conditioners or devices for centralized control are connected to the HRVs this indication may show During this indication appears on the display the ON OFF and timer operation may not be ...

Страница 19: ...ector Remote Controller for VRV BRC1A61 62 Every time the operation mode selector is pressed the operation mode display changes as shown below example When the FILTER indication appears on the display clean the filter of the HRV unit Independent Operation of The HRV Unit Using The Centralized Controller DCS302B61 After selecting the zone where the only the HRV unit operation is desired press the o...

Страница 20: ...Si 93 Maintenance 11 Part 3 Maintenance 1 Maintenance 13 1 1 Maintenance for The Air Filter 13 1 2 Maintenance for The Heat Exchange Element 16 ...

Страница 21: ...Si 93 12 Maintenance ...

Страница 22: ...part Be sure to turn off the OPERATION switch and disconnect the power CLEANING FREQUENCY AT LEAST ONCE EVERY TWO YEARS FOR GENERAL OFFICE USE CLEAN THE ELEMENT MORE FREQUENTLY IF NECESSARY 1 Go into ceiling through the inspection hole remove the hanging metals of maintenance cover and take it off VAM500 1000EJVE VAM2000EJVE 1 Maintenance Cover 2 Binding Metal 3 Hanging Metal 1 Maintenance Cover 2...

Страница 23: ... a vacuum cleaner If excessively dirty wash it in water 5 If the air filter is washed remove water completely and allow to dry Air filter for 20 to 30 minutes in the shade When dried completely install the air filter back in place Direct the indication INSIDE of the air filter toward the heat exchange elerment 1 Heat Exchange Element X2 2 Handle 3 Rail 4 Filter 1 Heat Exchange Element X4 2 Handle ...

Страница 24: ... not dry the air filter over a fire 3 Do not subject the air filter to direct sunlight 4 Do not use organic solvent such as gasoline and thinner on the air filter 5 Be sure to install the air filter after servicing Missing air filter causes clogged heat exchange element The air filter is an optional item and the replacement is available ...

Страница 25: ...of the heat exchange element Use the vacuum cleaner equipped with a brush on the tip of the suction nozzle Lightly contact the brush on the surface of the heat exchanging element when cleaning Do not crush the heat exchange element while cleaning 2 Install the air filter securely in place 3 Put the heat exchange element on the rail and insert it securely in place 4 Install the maintenance cover se...

Страница 26: ...Si 93 Control Functions 17 Part 4 Control Functions 1 Control Functions 19 1 1 List of Control Functions 19 1 2 Explanation of Individual Functions 20 ...

Страница 27: ...Si 93 18 Control Functions ...

Страница 28: ...r output based on temperature controller judgment Note 1 2 5 Pre cool pre heat function Prevents equipment operation for a preset time set time after air conditioner is turned on 2 6 Freshup function Sets motor tap so that supply air fan airflow rate is larger than exhaust air fan airflow rate 2 7 Filter sign function Stores cumulative operation hour data and turns on air filter cleaning indicator...

Страница 29: ...n Filter sign reset Stop Heat reclaim ventilation unit Ventilation fan motor Damper motor ventilation mode Normal ventilation Total heat exchange ventilation Remote controller indication Operation lamp ON ON Filter sign indicator ON ON HL020 Total heat exchange ventilation Operation Normal ventilation mode selection Air conditioner fan OFF Air conditioner fan ON Air conditioner ON OFF Operation Fa...

Страница 30: ...d 150 min 3 Others a Heat reclaim ventilation unit must be in non operating condition for two consecutive hours or more prior to pre cool pre heat operation b Temperature control mode of the air conditioner must be set to Cool Heat or Dry Note Operation standby indication is displayed only on LCD remote controller of heat reclaim ventilation unit Operation Normal ventilation mode selection Pre coo...

Страница 31: ...roller for air conditioner Allows independent operation of heat reclaim ventilation unit from VRV system remote controller during interim periods not possible when direct duct connection is used ON OFF operation is not possible from LCD remote controller of heat reclaim ventilation unit Operation Normal ventilation mode selection Air conditioner ON OFF Operation Fan motor Heat reclaim ventilation ...

Страница 32: ... controller for air conditioner Details of setting Mode Setting mode Setting switch No Setting position Operation method 01 02 03 04 05 06 Group No setting for centralized controller individual Field setting 00 30 Refer to P 54 Filter cleaning time setting 17 27 0 2500 hr 1250 hr No integration Refer to P 53 Pre cool pre heat On Off setting 2 Off On Pre cool pre heat time min setting 3 30 min 45 m...

Страница 33: ... supply air exhaust air 7 Supply Air Exhaust Air External input terminal function selection 8 Fresh up Overall alarm Overall malfunction Forced Off Fanforced Off Air flow increase KRP50 output changeover selection 9 Humidifying output Malfunction output Air flow setting 19 29 0 Low Low Low Low High High Ventilation mode setting 2 Automatic Total heat exchange Normal Fresh up operation 3 Off On Hum...

Страница 34: ...Si 93 Circuit Operations 25 Part 5 Circuit Operations 1 Circuit Operations 27 1 1 Circuit Configuration 27 1 2 Circuit Functions 28 ...

Страница 35: ...Si 93 26 Circuit Operations ...

Страница 36: ... motor relay Central data transmission interface circuit Remote control signal transmission interface circuit Relay drive circuit Microcomputer oscillation circuit Microcomputer reset circuit Control microcomputer Thermistor interface circuit Thermistor Airflow rate setting switch interface circuit Damper motor limit switch interface circuit Damper motor limit switch External input interface circu...

Страница 37: ...lay coils Fan motor damper motor relay Power supply relay for fan motor and damper motor Input Thermistor interface Uses thermistor temperature sensor to detect inside and outside temperatures Airflow rate setting switch interface Used to set airflow rate of main unit when dedicated remote controller is not used External input interface Used to control main unit with external contact point Freshup...

Страница 38: ...edicated LCD Remote Controller 38 1 9 Data Transmission Error Between LCD Remote Controller and Main Unit 39 1 10 Data Transmission Error LCD Remote Controller 40 1 11 Data Transmission Error Between LCD Master Remote Controller and Slave Remote Controller 41 1 12 Field Setting Error 42 1 13 Overlapping Central Control Address 43 1 14 Main Unit PCB Assembly 44 1 15 Dedicated LCD Remote Controller ...

Страница 39: ...Si 93 30 Troubleshooting ...

Страница 40: ...ashing Overall alarm P32 Flashing Flashing Overall malfunction P33 6 6 6 64 4 4 4 ON OFF Flashing Inside air thermistor error P34 6 6 6 65 5 5 5 ON OFF Flashing Outside air thermistor error P35 6 6 6 6A A A A ON OFF Flashing Damper system alarm P36 6 6 6 6A A A A Flashing Flashing Flashing Damper system thermistor error P37 U U U U5 5 5 5 Flashing Flashing Flashing Data transmission error between ...

Страница 41: ...ting Conditions When external input terminal J1 JC is shorted during operation Overall Alarm must be set in field setting mode Possible Causes Faulty external device Broken wire Faulty control PCB Troubleshooting Measure resistance between external input terminals J1 JC Is resistance 200 Ω or lower YES YES Remove the cause of error in connected external device Check wires for abnormalities broken ...

Страница 42: ...ting Conditions When external input terminal J1 JC is shorted during operation Overall Alarm must be set in field setting mode Possible Causes Faulty external device Broken wire Faulty control PCB Troubleshooting Measure resistance between external input terminals J1 JC Is resistance 200 Ω or lower YES YES Remove the cause of error in connected external device Check wires for abnormalities broken ...

Страница 43: ...on table when measuring resistance Thermistor temperature resistance conversion table If measured value deviates significantly from above values thermistor is faulty Use tester to check resistance Remove Indoor air thermistor R1T from X12A 3P on control PCB and measure resistance Is thermistor normal Note 1 YES NO Replace indoor air thermistor If there is no faulty contact replace control PCB HF00...

Страница 44: ...ion table when measuring resistance Thermistor temperature resistance conversion table If measured value deviates significantly from above values thermistor is faulty Use tester to check resistance Remove outdoor air thermistor R2T from X13A 2P on control PCB and measure resistance Is thermistor normal Note 1 YES NO Replace outdoor air thermistor If there is no faulty contact replace control PCB H...

Страница 45: ...contact in connector including relay connector Faulty control PCB assembly Troubleshooting Note Note 1 Place tester probes on connectors of limit switch Move switch by hand and check continuity If tester indicates 0Ω when limit switch turns on and infinity when it turns off limit switch is normal Place tester probes on connectors of damper motor and check resistance If tester indicates approx 17 k...

Страница 46: ...per motor or limit switch Faulty indoor air thermistor Faulty outdoor air thermistor Frosting Broken wire in cable Faulty contact in connector including relay connector Faulty control PCB assembly Troubleshooting Check error record on malfunction history display in service mode Is 64 recorded YES YES YES Take corrective measures specified for damper system error alarm Remove the cause of problem a...

Страница 47: ...CB assembly error Troubleshooting Dedicated Remote Controller Main Unit PCB Check to see if master slave remote controller is used Check microcomputer operation monitor on main unit PCB Is it flashing YES YES Change master slave selection switch to set proper master slave relation One should be set to Master and the other set to Slave Replace remote controller Replace main unit PCB Is master slave...

Страница 48: ... terminal board Check with power turned on With remote controller cable disconnected voltage between P1 and P2 on terminal board should be approx 16 VDC If measured value is not approx 16 VDC PCB assembly is faulty Connect remote controller cable and disconnect remote controller Voltage at the end of remote controller cable should be approx 16 VDC If measured value is not 16 VDC remote controller ...

Страница 49: ...on is not performed correctly for a certain time period Possible Causes Erroneous connection Faulty remote controller setting Faulty remote controller Troubleshooting Is master slave selection switch properly set YES YES Correct wiring Replace remote controller Set one master slave selection switch to Master and set the other to Slave Then turn off power and restart operation Replace either master...

Страница 50: ...onditions When data transmission is not performed correctly for a certain time period Possible Causes Faulty remote controller setting Faulty remote controller Troubleshooting NO NO Is master slave selection switch set to Master YES Is master slave remote control used Is master slave selection switch properly set YES Set master slave selection switch to Master Turn off power then restart Replace r...

Страница 51: ...controller cable Replace remote controller Is combination of remote controller and heat reclaim ventilation unit air conditioner correct NO HF011 Are 17 or more units connected to remote controller cable NO Refer Combination Right or Wrong Main body Remote controller Right Wrong Heat reclaim ventilation unit only Heat reclaim ventilation unit Right Heat reclaim ventilation unit only Heat reclaim v...

Страница 52: ... Remote controller microcomputer checks for double setting of addresses Error Generating Conditions When same address is set to two or more units Possible Causes Overlapping of central control address Faulty remote control Troubleshooting Change central control address settings using remote controller Then turn off power and restart Does equipment reset properly YES Replace remote controller End o...

Страница 53: ...roperly Is it flashing After checking other possible causes replace PCB assembly Is monitor indicator Off YES YES Monitor indicator remains On With remote controller disconnected check microcomputer operation monitor Turn off power then restart Noise may be causing erroneous operation If power reset does not solve the problem replace main unit PCB There may be a malfunction in main unit PCB fuse m...

Страница 54: ...ter check continuity between two wires in cable Is measured value MΩ infinity NO YES With remote controller cable disconnected from main unit PCB check voltage between P1 and P2 on main unit terminal board Is measured value approx 16 VDC NO YES Connect remote controller cable to main unit PCB and disconnect remote controller Check voltage at the end of cable on remote control side Is measured valu...

Страница 55: ... Option Check 2 Dedicated LCD remote controller Option Check 3 Dedicated LCD remote controller Option JC J2 J1 F2 F1 P2 P1 HL034 Main unit PCB JC J2 J1 F2 F1 P2 P1 HL035 Main unit PCB JC J2 J1 F2 F1 P2 P2 P1 P1 HL036 Main unit PCB LCD remote controller Remote controller for heat reclaim ventilation ...

Страница 56: ...or is faulty Use tester to check resistance NO YES Is resistance as shown below Thermistor is normal Remove thermistor from main unit PCB X12A X13A and check resistance using tester If measured value deviates significantly from values in the table thermistor is faulty HF015 Thermistor temperature Sensor resistance Thermistor temperature Sensor resistance 10ºC or less 108kΩ or more 22ºC Approx 23kΩ...

Страница 57: ...esistance between secondary side of transformer and case 100 MΩ or higher Insulation resistance between primary side and secondary side of transformer 100 MΩ or higher Check resistance of primary side of transformer Does measured resistance deviate significantly from values shown below YES NO Check resistance of secondary side of transformer Does measured resistance deviate significantly from valu...

Страница 58: ...esistance and voltage DAMPER MOTOR NO YES YES Is measured value 0 Ω when limit switch turns on and infinity when it turns off Damper motor is normal Place tester probes at connectors of limit switch and check continuity while moving switch by hand Limit switch is faulty Damper motor is faulty HF017 NO Is measured value of EJ type approx 17 kΩ Place tester probes on connectors of damper motor and c...

Страница 59: ...Troubleshooting Si 93 50 Troubleshooting ...

Страница 60: ...Si 93 Supplementary Explanation 51 Part 7 Supplementary Explanation 1 Supplementary Explanation 53 1 1 Field Setting Service Mode Operation 53 ...

Страница 61: ...Si 93 52 Supplementary Explanation ...

Страница 62: ...Step 1 With equipment in normal mode press the button for more than 4 seconds to enter field setting mode Step 2 Mode No UP Mode No DOWN Use MODE and AIR VOLUME to select desired mode No Step 3 To setting heat reclaim ventilation units by group press button and select desired unit No Step 4 Press button to select desired setting switch No Step 5 Press button to select desired setting position No S...

Страница 63: ...ing mode Mode No Group No 3 4 1 5 HL040 2 Step 1 With equipment in normal mode press the button for more than 4 seconds to enter field setting mode Step 2 Mode No UP Mode No DOWN Use MODE and AIR VOLUME to select mode No 00 30 Step 3 Press or button to select Group No Step 4 Press button once to enter settings Step 5 Press button to return to normal mode ...

Страница 64: ...n on the forced fan Mode No 43 Step 1 With equipment in field setting mode press the button for more than 4 seconds to enter service mode Step 2 Mode No UP Mode No DOWN Use MODE and AIR VOLUME to select mode No 43 Step 3 Use to select desired Unit No Step 4 Press button to return to normal mode ...

Страница 65: ...g mode Mode No Step 1 With equipment in field setting mode press the button for more than 4 seconds to enter service mode Step 2 Mode No UP Mode No DOWN Use MODE and AIR VOLUME to select mode No 45 Step 3 Use to select setting Unit No Step 4 Press or button to select Unit No after reallocation Step 5 Press button once to enter settings Step 6 Press button to return to normal mode ...

Страница 66: ...ype andcooling heating selection privilege Note Note 1 Only master remote controller can display flashing Operation changeover control when cooling heating selection privilege is not set New heat reclaim ventilation unit System A Air conditioner VRV system Without selection privilege System B With selection privilege Operation changeover control Remote controller for air conditioner Slave setting ...

Страница 67: ...ay 40 Sensor data 41 Forced fan ON 43 Individual setting 44 Unit No reallocation 45 Step 1 To field setting mode Press for more than 4 sec Step 2 Mode No selection 1 Mode 00 30 Mode 40 49 Mode 50 59 Press for more than 4 sec Press for more than 4 sec Step 3 Mode No selection 2 Mode No UP Mode No DOWN Step 4 Switch No selection Switch No selection Step 5 Position selection Position selection Step 6...

Страница 68: ...t LCD LCD is equipped with a new function that graphically displays currently selected ventilation mode as shown below HL045 Ventilation mode Auto Total heat exchange ventilation mode Normal ventilation mode Display OFF in automatic ventilation mode Ventilation mode Total heat exchange Ventilation mode Normal Normal ventilation mode HL046 HL047 HL048 HL049 HL050 Display can be turned off using fie...

Страница 69: ...e Freshup setting changes as follows Inspection Inspection operation is shown below With Freshup Low Low High High Low Freshup High Freshup Without Freshup Function modes change in sequence every time button is pressed HL051 Inspection indication flashes Normal screen Cyclic Unit 0 Error code 00 Inspection HL052 ...

Страница 70: ...same group control system However the setting of selected units can be fixed by the following method Example This setting method can be used when a group control system is connected with units having a different airflow capacity from other units in the system 1 Press for more than 4 seconds 2 Set mode No to 44 using or 3 Set unit No using 4 Set airflow volume ventilation mode using 5 Set airflow d...

Страница 71: ...62 Supplementary Explanation Individual Settings Heat Reclaim Ventilation Unit Air Conditioner Ventilation Volume Ventilation Mode Airflow Volume Airflow Direction As indicated by LCD As indicated by LCD Low 1 P0 0 High 3 P4 4 Swing 5 ...

Страница 72: ...Si 93 Appendix 63 Part 8 Appendix 1 Appendix 65 1 1 Wiring Diagram 65 ...

Страница 73: ...Si 93 64 Appendix ...

Страница 74: ...Si 93 Appendix Appendix 65 1 Appendix 1 1 Wiring Diagram VAM500EJVE VAM800EJVE VAM1000EJVE ...

Страница 75: ...Appendix Si 93 66 Appendix VAM2000EJVE ...

Страница 76: ... LCD Master Remote Controller and Slave Remote Controller 41 Data Transmission Error Between LCD Remote Controller and Main Unit 39 Data Transmission Error LCD Remote Controller 40 Dedicated LCD Remote Controller 38 45 Dedicated Remote Controller 38 Direct duct connection with air conditioner 20 Display OFF in automatic ventilation mode 59 Duct Connection Flange 3 4 E EEPROM 28 Error Code 60 31 64...

Страница 77: ...geover Control 57 Operation chart 20 Operation for INDIVIDUAL SYSTEM 8 Operation mode selector 10 Operation with The Remote Control for Air Conditioning Operation HRV Units BRC301B61 8 Outdoor Air 3 4 Outdoor Air Thermistor Error 35 Overall Alarm 32 Overall Malfunction 33 Overlapping Central Control Address 43 P Power ON operation function 19 Power supply circuit 28 Power Transformer 48 Power tran...

Страница 78: ...ode indication ON OFF 24 Ventilation mode setting 24 Ventilation mode otal heat exchange 59 Ventilation Operation Control 20 Ventilation operation control function 19 Ventilation volume Freshup setting changes 60 W When no indication is displayed on remote controller 45 ...

Страница 79: ...Si 93 iv Index ...

Страница 80: ... TO OPERATE WITH TIMER 9 I Initial setting mode Nos 17 27 18 28 53 Inspection operation 60 L LCD and Operation Panel 59 M Main Unit PCB 38 Main unit PCB 44 Maintenance Cover VAM2000EJVE 13 VAM500 1000EJVE 13 Maintenance for The Heat Exchange Element 16 N Normal ventilation mode 59 O Operation Changeover Control 57 Operation for Each System 7 operation mode selector 10 P Power Transformer 48 Pre co...

Страница 81: ...Si 93 vi Drawings Flow Charts When no indication is displayed on remote controller 45 Wiring Diagram 65 ...

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