Panasonic WH-UD28AE Service Manual Download Page 15

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6 Refrigeration And Water Cycle Diagram

* If piping length is over common length, additional refrigerant should be added as shown in the table.

Piping size

Rated

Length

(m)

Common

Length

(m)

Max

Elevation

(m)

Min.

Piping

Length

(m)

Max.

Piping

Length

(m)

Additional

Refrigerant

(g/m)

Model

Gas

Liquid

D24AE

5/8”

1/4”

D28AE

5/8”

1/4”

Summary of Contents for WH-UD28AE

Page 1: ... 5 2 2 WH SD28AE WH UD28AE 7 3 Features 9 4 Location of Controls and Components 10 4 1 Indoor Unit 10 4 2 Outdoor Unit 12 5 Dimensions 13 5 1 Indoor Unit 13 5 2 Outdoor Unit 14 6 Refrigeration And Water Cycle Diagram 15 7 Block Diagram 16 8 Wiring Connection Diagram 17 8 1 Indoor Unit 17 8 2 Outdoor Unit 18 9 Electronic Circuit Diagram 19 9 1 Indoor Unit 19 9 2 Outdoor Unit 20 10 Printed Circuit B...

Page 2: ...tem 39 16 2 Relationship Between The Condition Of The Air to Water Heatpump Indoor And Outdoor Units And Pressure And Electric Current 40 16 3 Breakdown Self Diagnosis Function 41 16 4 Error Codes Table 42 16 5 Self diagnosis Method 43 17 Disassembly and Assembly Instructions 67 17 1 To Remove Front Plate 67 17 2 To Remove Cabinet 67 17 3 To Remove Pressure Gauge 68 17 4 To Remove Control Panel 68...

Page 3: ...d cross over the handrail and causing accident 9 For electrical work follow the local national wiring standard regulation and the installation instruction An independent circuit and single outlet must be used If electrical circuit capacity is not enough or defect found in electrical work it will cause electrical shock or fire 10 This equipment must be properly earthed Earth line must not be connec...

Page 4: ...rature control please set it to 700 20 F 370 10 C Pb free solder will tend to splash when heated too high about 1100 F 600 C 7 Power supply connection to the indoor unit 1 Power supply point should be in easily accessible place for power disconnection in case of emergency 2 In some countries permanent connection of Air to Water Heatpump to the power supply is prohibited 3 Connect the power supply ...

Page 5: ...3 0 Pipe Length Range m ft 3 9 8 30 98 4 I D O D Height Difference m ft 20 65 6 Additional Gas Amount g m oz ft 30 0 3 Refrigeration Charge Less m ft 10 32 8 Compressor Type Hermetic Motor Motor Type Brushless 4 poles Rated Output kW 1 70 Fan Type Propeller Fan Material PP Motor Type Induction 6 poles Input Power W 153 Output Power W 76 Fan Speed Lo Hi rpm 540 700 Heat Exchanger Fin material Alumi...

Page 6: ...ower Level dB 43 Dimension Height mm inch 644 25 11 32 Width mm inch 504 19 27 32 Depth mm inch 295 11 5 8 Net Weight kg lbs 26 57 Refrigerant Pipe Diameter Liquid mm inch 6 35 1 4 Gas mm inch 15 88 5 8 Water Pipe Diameter Inlet mm inch 22 23 7 8 Outlet mm inch 22 23 7 8 Water Drainage Diameter mm inch 15 9 16 Pump Motor Type Capacitor Run Induction Motor 2 5 μF No of Speed 3 Input Power W 100 Hot...

Page 7: ...ence m ft 20 65 6 Additional Gas Amount g m oz ft 30 0 3 Refrigeration Charge Less m ft 10 32 8 Compressor Type Hermetic Motor Motor Type Brushless 4 poles Rated Output kW 1 70 Fan Type Propeller Fan Material PP Motor Type Induction 6 poles Input Power W 153 Output Power W 76 Fan Speed Lo Hi rpm 540 700 Heat Exchanger Fin material Aluminium Pre Coat Fin Type Corrugated Fin Row Stage FPI 2 30 19 Si...

Page 8: ... 11 32 Width mm inch 504 19 27 32 Depth mm inch 295 11 5 8 Net Weight kg lbs 26 57 Refrigerant Pipe Diameter Liquid mm inch 6 35 1 4 Gas mm inch 15 88 5 8 Water Pipe Diameter Inlet mm inch 22 23 7 8 Outlet mm inch 22 23 7 8 Water Drainage Diameter mm inch 15 9 16 Pump Motor Type Capacitor Run Induction Motor 2 5 μF No of Speed 3 Input Power W 100 Hot Water Coil Type Brazed Plate No of Plates 48 Si...

Page 9: ...vent compressor reverse cycle Inner protector to protect compressor Serviceability Improvement Breakdown Self Diagnosis function System Status Check Buttons for servicing purpose System Pumpdown Button for servicing purpose Front maintenance design for outdoor unit Operation Condition DBT Dry bulb temperature WBT Wet bulb temperature NOTICE When the outdoor temperature is out of the above temperat...

Page 10: ...10 4 Location of Controls and Components 4 1 Indoor Unit 4 1 1 Location of Control ...

Page 11: ...11 ...

Page 12: ...12 4 1 2 Main Components 4 2 Outdoor Unit ...

Page 13: ...13 5 Dimensions 5 1 Indoor Unit ...

Page 14: ...14 5 2 Outdoor Unit ...

Page 15: ...on length additional refrigerant should be added as shown in the table Piping size Rated Length m Common Length m Max Elevation m Min Piping Length m Max Piping Length m Additional Refrigerant g m Model Gas Liquid D24AE 5 8 1 4 7 10 20 3 30 30 D28AE 5 8 1 4 7 10 20 3 30 30 ...

Page 16: ...16 7 Block Diagram ...

Page 17: ...17 8 Wiring Connection Diagram 8 1 Indoor Unit ...

Page 18: ...18 8 2 Outdoor Unit ...

Page 19: ...19 9 Electronic Circuit Diagram 9 1 Indoor Unit ...

Page 20: ...20 9 2 Outdoor Unit ...

Page 21: ...21 10 Printed Circuit Board 10 1 Indoor Unit 10 1 1 Main Printed Circuit Board ...

Page 22: ...22 10 2 Outdoor Unit 10 2 1 Main Printed Circuit Board ...

Page 23: ...23 10 2 2 Capacitor Printed Circuit Board 10 2 3 Noise Filter Printed Circuit Board ...

Page 24: ...esigned for indoor installation only OUTDOOR UNIT If an awning is built over the unit to prevent direct sunlight or rain be careful that heat radiation from the condenser is not obstructed There should not be any animal or plant which could be affected by discharged hot or cold air Keep the spaces indicated by arrows from wall ceiling fence or other obstacles Do not place any obstacles which may c...

Page 25: ... indoor unit are used for connection to water circuit Please request a licensed technician to install this water circuit This water circuit must comply with all relevant European and national regulations i e IEC EN 61770 Be careful not to deform the piping with excessive force when doing piping connection job Do not install any valve between indoor unit and water piping to avoid accidental closure...

Page 26: ...drain hose in the market This hose must to be installed in a continuosly downward direction and in a frost free environment Guides this hose s outlet to outdoor only Do not insert this hose into sewage hose or cleaning hose that may generate ammonia gas sulfuric gas etc If necessary use hose clamp to further tighten the hose at drain hose connector to prevent it leakage 11 3 4 CONNECT THE CABLE TO...

Page 27: ...57 or heavier cord to the terminal board and connect the other end of the cable to isolating device Disconnecting means 3 To avoid cable harmed by sharp edge cables must go through bushing located at the bottom of indoor unit before carry out electrical connection The bushing must be used and must not take off 11 3 4 1 Wire Stripping and Connecting Requirement Terminal screw Tightening torque NO c...

Page 28: ...hen tighten with torque wrench to the specified torque as stated in the table Local pipes can project in any of four directions Make holes in the pipe panels for the pipes to pass through Be sure to install the pipe panels to prevent rain from getting inside the outdoor unit Removing the service panel 1 Remove the two mounting screws 2 Slide the service panel downward to release the pawls After th...

Page 29: ...oes not move after approximately five minutes Note BE SURE TO FOLLOW THIS PROCEDURE IN ORDER TO AVOID REFRIGERANT GAS LEAKAGE 5 Disconnect the charging hose from the vacuum pump and from the service port of the 3 way valve 6 Tighten the service port caps of the 3 way valve at a torque of 18 NO m with a torque wrench 7 Remove the valve caps of both of the 2 way valve and 3 way valve Position both o...

Page 30: ...es and cord together with the binding strap so that they do not touch other parts such as the compressor and bare copper pipes Secure the cable onto the control board with the holder clamper 11 4 4 1 Wire Stripping and Connecting Requirement Same as indoor requirement For details please refer the diagram on AIR TO WATER HEATPUMP INDOOR UNIT section 11 3 4 CONNECT THE CABLE TO THE INDOOR UNIT 11 4 ...

Page 31: ...r setting temperature and water outlet temperature 12 1 1 Internal Water Setting Temperature Once the operation starts control panel setting temperature will be taken as base value for temperature shifting processes These shifting processes are depending on the Air to Water Heatpump settings and the operation environment The final shifted value will be used as internal water setting temperature an...

Page 32: ... 4 Outdoor Fan Motor Operation Outdoor fan motor operates with two fan speed Hi and Lo It starts when compressor starts operation and it stops 30 seconds after compressor stops operation 12 2 Water Pump 12 2 1 Water Pump Control 1 Once the indoor unit is ON the water pump will turn ON immediately No error judgement for 9 minutes However during this 9 minutes if there is any abnormality the compres...

Page 33: ...serve as an overload protector that shuts down the unit when the water level is detected to be low 2 Detection is Lo 0V when there is no water flow and detection is Hi 5V when there is water flow 12 5 Auto Restart Control 1 When the power supply is cut off during the operation of Air to Water Heatpump the compressor will re operate within three to four minutes there are 10 patterns between 2 minut...

Page 34: ...lay 3 minutes when the IPM temperature decreases to 90 C B DC Peak Current Control 1 When the current to IPM exceeds set value of 30 0 5 0 A compressor will stop Compressor will restart after three minutes 2 If the set value exceeds again for more than 30 seconds after the compressor restarts operation will restart after two minutes 3 If the set value exceeds again for more than 30 seconds after t...

Page 35: ...itions When abnormal high voltage detection 5V or when open circuit detection 0V for 5 seconds continuously After detection When abnormality is detected continue 5 seconds unit stop operation Error H64 will be displayed 13 2 Protection Control For Heating Operation 13 2 1 Outdoor Air Temperature Control The maximum current value is regulated when the outdoor air temperature rises above 14 C in ord...

Page 36: ...oblem contact your local authorized dealer 14 2 Proper Pump Down Procedure 1 Press the PUMPDW button on control panel to begin PUMP DOWN mode Operate the system in PUMP DOWN mode for 10 15 minutes 2 After 10 15 minutes after 1 or 2 minutes in case very low ambient temperatures 10 C close 2 way valve 3 After 3 minutes close 3 way valve and press the OFF ON button on control panel to stop PUMP DOWN ...

Page 37: ...ut the filter carefully so that not deforms it shape Use tap water only to wash the residue on the filter If necessary gently use soft brush only to clean the hard dirt After clean put it back to the original location and tighten the nut connection with torque wrench 3 Pressure relief valve Check for correction operation of pressure relief valve by turn up the level to become horizontal Refer to f...

Page 38: ...rcuit Turn up the level to become horizontal Refer to figure Pressure relief valve The trapped air will be drained out together with water After few seconds turn down the level to stop the water drainage Repeat it until the bubbling sound disappear ...

Page 39: ...no electrical problems before inspecting the refrigeration cycle Such problems include insufficient insulation problem with the power source malfunction of a compressor and a fan The normal pressure of the refrigeration cycle depends on various conditions the standard values for them are shown in the table on the right ...

Page 40: ...essure electric current and temperature fifteen minutes after an operation is started Heating Mode Condition of the Air to Water Heatpump indoor and outdoor units Low Pressure High Pressure Electric current during operation Insufficient refrigerant gas leakage Clogged capillary tube or Strainer Heat radiation deficiency of the outdoor unit Inefficient compression ...

Page 41: ...RESET button to reset or clear the error code The last error code Abnormality will be stored in IC memory To make a diagnosis 1 Operation LED start to blink and the unit automatically stops the operation 2 The error code Abnormality will be displayed on the system error display 3 An abnormality error refer to the Error Code Table To display memorized error Protective operation status 1 Turn power ...

Page 42: ...in Water flow switch H63 Refrigerant low pressure abnormality Continue for 5 sec Outdoor low pressure sensor defective or disconnected H64 Refrigerant high pressure abnormality Continue for 5 sec Outdoor high pressure sensor defective or disconnected H65 Indoor control panel communication abnormality Indoor control panel defective or disconnected H66 Compressure low pressure abnormality Compressor...

Page 43: ...ther it is normal Malfunction Caused 1 Faulty outdoor unit PCB 2 Faulty indoor unit PCB 3 Indoor outdoor signal transmission error due to wrong wiring 4 Indoor outdoor signal transmission error due to breaking of wire in the connection wires between the indoor and outdoor units 5 Indoor outdoor signal transmission error due to disturbed power supply waveform Abnormality Judgment 1 min after operat...

Page 44: ...ing in between 20 70Vdc outdoor PCB is in good condition 16 5 2 Indoor Water Outlet Temperature Sensor Abnormality H14 Malfunction Decision Conditions During startup and operation of heating the temperatures detected by the indoor water outlet temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Con...

Page 45: ...ion Conditions During startup and operation of heating the temperatures detected by the compressor temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds ...

Page 46: ...onditions A current transformer CT is detected by checking the compressor running frequency rated frequency and CT detected input current less than 0 65A for continuously 20 seconds Malfunction Caused 1 CT defective 2 Outdoor PCB defective 3 Compressor defective low compression ...

Page 47: ...ion Conditions During startup and operation of heating the temperatures detected by the indoor refrigerant liquid temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds ...

Page 48: ...ion Conditions During startup and operation of heating the temperatures detected by the outdoor air temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds ...

Page 49: ...ion Conditions During startup and operation of heating the temperatures detected by the outdoor pipe temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds ...

Page 50: ...ion Conditions During startup and operation of heating the temperatures detected by the outdoor discharge pipe temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds ...

Page 51: ...H33 Malfunction Decision Conditions The supply power is detected for its requirement by the indoor outdoor transmission Malfunction Caused 1 Wrong models interconnected 2 Wrong indoor unit and outdoor unit PCBs used 3 Indoor unit or outdoor unit PCB defective ...

Page 52: ...ng the water flow detected by the indoor water flow switch is used to determine water flow error Malfunction Caused 1 Water leak in system 2 Faulty connector connection 3 Faulty switch 4 Faulty PCB Abnormality Judgment Continue for 1 minute but no judgment for 9 minutes after compressor startup restart ...

Page 53: ...ons During operation of heating the outdoor low pressure sensor output signal is 0Vdc or 5Vdc Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds but no judgment for 5 minutes after compressor startup restart ...

Page 54: ...ons During operation of heating the outdoor high pressure sensor output signal is 0Vdc or 5Vdc Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds but no judgment for 5 minutes after compressor startup restart ...

Page 55: ...Abnormality H65 Malfunction Decision Conditions During standby and operation of heating indoor control panel error occur Malfunction Caused 1 Faulty connector connection 2 Faulty control panel 3 Faulty PCB Abnormality Judgment Continue for 1 minute ...

Page 56: ...EPROM Malfunction Decision Conditions During operation of heating pressure 0 2 MPa and below is detected by the outdoor low pressure sensor Malfunction Caused 1 Dust accumulation on the outdoor unit heat exchanger 2 Air short circuit 3 Refrigerant shortage refrigerant leakage 4 Detection error due to faulty outdoor unit main PCB ...

Page 57: ...sion Conditions During startup and operation of heating the temperatures detected by the indoor water inlet temperature sensor are used to determine sensor error Malfunction Caused 1 Faulty connector connection 2 Faulty sensor 3 Faulty PCB Abnormality Judgment Continue for 5 seconds ...

Page 58: ...M Malfunction Decision Conditions During operation of heating pressure 4 0 MPa and above is detected by outdoor high pressure sensor Malfunction Caused 1 Dust accumulation on the indoor unit heat exchanger 2 Detection error due to faulty indoor pipe temperature sensor 3 Detection error due to faulty indoor unit PCB ...

Page 59: ...tions During operation of heating temperature below 0 C is detected by indoor pipe temperature sensor Malfunction Caused 1 Connector in poor contact 2 Faulty sensor 3 Faulty outdoor unit PCB 4 Four way valve defective Abnormality Judgment Continue 4 times in 30 minutes ...

Page 60: ...on of heating PFC protection circuitry at the outdoor unit main PCB senses abnormal high DC voltage level Malfunction Caused 1 DC voltage peak due to power supply surge 2 DC voltage peak due to compressor windings not uniform 3 Faulty outdoor unit PCB Abnormality Judgment Continue 4 times in 10 minutes ...

Page 61: ...of heating running current 0 65A I 1 65A 3 During operation of heating indoor pipe water inlet 5 C Malfunction Caused 1 Refrigerant shortage refrigerant leakage 2 Poor compression performance of compressor 3 2 3 way valve closed 4 Detection error due to faulty water inlet or indoor pipe temperature sensors Abnormality Judgment Continue 2 times in 20 minutes ...

Page 62: ...Conditions A compressor rotation failure is detected by checking the compressor running condition through the position detection circuit Malfunction Caused 1 Compressor terminal disconnect 2 Outdoor PCB malfunction Abnormality Judgment Continue 4 times in 20 minutes ...

Page 63: ...tdoor IPM temperature sensor Malfunction Caused 1 IPM overheat due to short circuit of hot discharge air flow 2 IPM overheat due to defective of outdoor fan motor 3 IPM overheat due to defective of internal circuitry of IPM 4 IPM overheat due to defective IPM temperature sensor Abnormality Judgment Continue 3 times in 30 minutes ...

Page 64: ... heating temperature above 112 C is detected by the compressor tank temperature sensor Malfunction Caused 1 Refrigerant shortage refrigerant leakage 2 2 3 way valve closed 3 Detection error due to faulty compressor tank temperature sensor Abnormality Judgment Continue 4 times in 30 minutes ...

Page 65: ... is detected by the outdoor current transformer CT Malfunction Caused 1 Over current due to compressor failure 2 Over current due to defective outdoor unit PCB 3 Over current due to defective inverter main circuit electrolytic capacitor 4 Over current due to excessive refrigerant Abnormality Judgment Continue 3 times in 20 minutes ...

Page 66: ...eration of heating outdoor current above 30 0 5 0 A is detected by the IPM DC Peak sensing circuitry Malfunction Caused 1 DC peak due to compressor failure 2 DC peak due to defective power transistor s 3 DC peak due to defective outdoor unit PCB Abnormality Judgment Continue for 7 times ...

Page 67: ...nting screws which located at bottom of the front plate 2 Gently pull the lower section of the front plate towards you to remove the front plate from left and right hooks 3 Hold the left edge and right edge of front plate to lift up front plate from hooks 17 2 To Remove Cabinet WARNING High Voltage are generated in the electrical parts area by the capacitor Ensure that the capacitor has discharged...

Page 68: ...68 17 3 To Remove Pressure Gauge 17 4 To Remove Control Panel ...

Page 69: ...69 17 5 To Remove Electronic Controller Board and Transformer 17 6 To Remove RCCB ...

Page 70: ...70 17 7 To Remove Pressure Relief Valve Flow Switch and Water Pump When reinstall the water pipe use grease or water at the joining When reinstall the water pipe use grease or water at the joining ...

Page 71: ...71 When reinstall the water pipe use grease or water at the joining ...

Page 72: ...racteristics 18 1 1 WH SD24AE WH UD24AE Heating Characteristics at Different Outdoor Air Temperature Condition Outdoor air temperature 7 C DBT 6 C WBT Indoor water inlet temperature 30 C Indoor water outlet temperature 35 C Piping length 7m ...

Page 73: ...73 Heating Characteristics at Different Piping Length Condition Outdoor air temperature 7 C DBT 6 C WBT Indoor water inlet temperature 30 C Indoor water outlet temperature 35 C Piping length 7m ...

Page 74: ...D28AE WH UD28AE Heating Characteristics at Different Outdoor Air Temperature Condition Outdoor air temperature 7 C DBT 6 C WBT Indoor water inlet temperature 30 C Indoor water outlet temperature 35 C Piping length 7m ...

Page 75: ...75 Heating Characteristics at Different Piping Length Condition Outdoor air temperature 7 C DBT 6 C WBT Indoor water inlet temperature 30 C Indoor water outlet temperature 35 C Piping length 7m ...

Page 76: ...7 21 1 48 7 00 1 59 6 73 1 78 6 21 1 95 5 87 2 11 HC Heating Capacity kW IP Power Input kW LWC Leaving Water Condenser Temperature C Tamb Ambient Temperature C LWC 30 35 40 45 50 Tamb HC IP HC IP HC IP HC IP HC IP 15 3 62 1 82 3 58 2 01 3 32 2 16 3 07 2 36 2 91 2 53 7 6 10 2 18 6 04 2 39 5 79 2 57 5 37 2 80 5 10 3 00 2 8 71 2 73 8 65 2 99 8 25 3 24 7 62 3 55 7 20 3 85 7 9 09 2 01 9 00 2 20 8 59 2 ...

Page 77: ...ploded View and Replacement Parts List 19 1 WH SD24AE WH SD28AE Note The above exploded view is for the purpose of parts disassembly and replacement The non numbered parts are not kept as standard service parts ...

Page 78: ...811022 10 RETAINING RING D 22mm 2 CWH581007 11 WATER FLOW SWITCH 1 CWB621034 12 PACKING O RING I D 21 8mm 2 CWB811040 13 RETAINING RING D 32mm 2 CWH581019 14 ELECTRONIC CONTROLLER MAIN 1 CWA73C3566 CWA73C3567 O 15 TERMINAL BOARD ASS Y 1 CWA28K1076J O 16 RESIDUAL CURRENT CIRCUIT BREAKER 1 CWA181004 O 17 TRANSFORMER COMPLETE 1 CWA40C1057 O 18 SENSOR COMPLETE 1 CWA50C2588 O 19 REMOTE CONTROL COMPLETE...

Page 79: ...79 19 2 WH UD24AE WH UD28AE ...

Page 80: ...80 ...

Page 81: ...81 Note The above exploded view is for the purpose of parts disassembly and replacement The non numbered parts are not kept as standard service parts ...

Page 82: ...C2185 28 CABINET REAR PLATE CO 1 CWE02C1051 29 CONTROL BOARD ASS Y 1 CWH10K1046 32 TERMINAL BOARD ASS Y 1 CWA28K1076J 33 CAPACITOR FAN MOTOR 3 5μF 440V 1 DS441355NPQA O 34 ELECTRONIC CONTROLLER CAPACITOR 1 CWA745089 O 38 ELECTRONIC CONTROLLER NOISE FILTER 1 CWA745501 O 44 ELECTRONIC CONTROLLER MAIN 1 CWA73C3576R CWA73C3577R O 46 REACTOR 2 G0C423J00001 48 TERMINAL COVER 1 CWH171039A 49 NUT FOR TERM...

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