Revision A: • A warning when opening or closing the valve has been added. OBH875 is void. OUTDOOR UNIT SERVICE MANUAL HFC utilized R410A No. OBH875 REVISED EDITION-A Models MUZ-GS30NA MUZ-GS36NA MUY-GS30NA MUY-GS36NA - U1 - U1 - U1 - U1 MUZ-GS30NAH MUZ-GS36NAH - U1 - U1 Indoor unit service manual MSZ-GS•NA, MSY-GS•NA Series (OBH874) CONTENTS 1. TECHNICAL CHANGES·······························2 2. PART NAMES AND FUNCTIONS···················3 3.
Use the specified refrigerant only Never use any refrigerant other than that specified. Doing so may cause a burst, an explosion, or fire when the unit is being used, serviced, or disposed of. Correct refrigerant is specified in the manuals and on the spec labels provided with our products. We will not be held responsible for mechanical failure, system malfunction, unit breakdown or accidents caused by failure to follow the instructions. Prepare the proper tools.
2 PART NAMES AND FUNCTIONS MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA Air inlet (back and side) Piping Air outlet Drain hose Drain outlet OBH875A 3
3 SPECIFICATION MUZ-GS30NA MUZ-GS30NAH MUY-GS30NA MUZ-GS36NA MUZ-GS36NAH MUY-GS36NA 30,700 (10,300 ~ 30,700) 32,000/33,200 (10,300 ~ 32,000)/(10,300 ~ 33,200) Heating 47 *1,3 Btu/h 32,600 (9,800 ~ 34,000) 35,200 (9,800 ~ 36,000) Heating 17 *2,3 Btu/h 20,000 (20,800) 21,600 (22,800) W 3,320 (650 ~ 3,320) 3,630/3,770 (650 ~ 3,630)/(650 ~ 3,770) Heating 47 *1,3 W 3,340 (590 ~ 3,580) 3,740 (590 ~ 4,000) Power consumption Heating 17 *2,3 W Rated (Maximum) 2,500 (2,600) 2,770 (2,920) 9.2 [18.
Test condition *4, *5 AHRI 210/240 Mode Indoor air condition (°F) Dry bulb Wet bulb Test Outdoor air condition (°F) Dry bulb Wet bulb "A-Full" Cooling Steady State at rated compressor speed 80 67 95 (75) "B-Full" Cooling Steady State at rated compressor speed 80 67 82 (65) SEER "B-Low" Cooling Steady State (Cooling) at minimum compressor speed 80 67 82 (65) "F-Low" Cooling Steady State at minimum compressor speed 80 67 67 (53.
4 OUTLINES AND DIMENSIONS MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA Unit: inch BASICALLY OPEN 20 in OR MORE WITHOUT ANY OBSTRUCTION IN FRONT AND BOTH SIDES OF THE UNIT. REQUIRED SPACE 14 in OR MORE. 4 in OR MORE. 16-7/16 AIR IN ↓ AIR OUT 15-3/8 20 in OR MORE. OPEN TWO SIDES OF RIGHT OR REAR SIDE. 4 in OR MORE.
5 WIRING DIAGRAM MUZ-GS30NA MUZ-GS36NA MUZ-GS30NAH MUZ-GS36NAH OBH875A 7
MUY-GS30NA MUY-GS36NA OBH875A 8
6 REFRIGERANT SYSTEM DIAGRAM MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA Unit: inch (mm) Service port (high pressure) Refrigerant pipe ø5/8 (with heat insulator) Muffler 4-way valve Strainer #100 Stop valve Flared connection Discharge temperature thermistor RT62 (Only GS30/36NAH) Defrost thermistor RT61 Outdoor heat exchanger Ambient temperature thermistor RT65 ACC Service port (low pressure) Flared connection Strainer #100 Stop valve Refrigerant pipe ø1/4 (with heat i
MAX. REFRIGERANT PIPING LENGTH and MAX. HEIGHT DIFFERENCE Model Refrigerant piping: ft. Max. Length Max. Height difference A B MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA 100 Piping size O.D: in. 50 Gas Liquid 5/8 1/4 Indoor unit Max. Height difference B Max. Length A Outdoor unit ADDITIONAL REFRIGERANT CHARGE (R410A: oz.) NOTE: Refrigerant piping exceeding 25 ft. requires additional refrigerant charge according to the calculation.
7 DATA MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA 7-1. PERFORMANCE DATA 1) COOLING CAPACITY Indoor air Model 71 TC 37.6 SHC 22.1 SHF 0.59 Outdoor intake air DB temperature (˚F) 85 TPC TC SHC SHF TPC TC 2.95 35.2 20.6 0.59 3.24 33.0 67 35.6 25.6 0.72 2.79 33.2 23.9 0.72 3.07 30.7 22.1 0.72 3.32 63 33.5 28.6 0.85 2.66 31.0 26.5 0.85 2.94 28.9 24.6 0.85 3.
4) HEATING CAPACITY Indoor air Model IDB (˚F) MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH 75 70 65 75 70 65 75 70 65 75 70 65 5 TC 14.3 15.5 16.3 14.3 15.5 16.3 15.5 16.7 17.6 15.5 16.7 17.6 15 TPC 1.97 1.89 1.80 2.09 2.01 1.92 2.21 2.11 2.02 2.33 2.23 2.14 TC 18.9 20.0 20.5 18.9 20.0 20.5 20.4 21.6 22.2 20.4 21.6 22.2 TPC 2.49 2.40 2.30 2.61 2.52 2.42 2.79 2.69 2.58 2.91 2.81 2.70 Outdoor intake air WB temperature (˚F) 25 35 43 TC TPC TC TPC TC TPC 23.6 2.92 28.2 3.26 31.8 3.42 24.5 2.86 28.
Total power consumption (kW) MUZ-GS36NA MUZ-GS36NAH MUY-GS36NA (230V) SHF at rating condition = 0.69 Airflow = 823 CFM 5.2 71 67 63 4.2 3.2 rature (°F) air WB tempe Indoor intake 2.2 1.2 0.2 65 75 85 95 105 Outdoor intake air DB temperature (°F) 115 This value of frequency is not the same as the actual frequency in operating. Refer to 7-5 and 7-6 for the relationships between frequency and capacity. Heating Heating capacity (at Rated frequency) 59 68 79 Capacity correction factor 1.2 1.1 1.
7-3. CONDENSING PRESSURE Cooling Data are based on the condition of indoor humidity 50 %. Air flow should be set to High speed.
Heating Data are based on the condition of outdoor humidity 75%. Air flow should be set to High speed. Data are for heating operation without any frost.
7-4. STANDARD OPERATION DATA MSZ-GS30NA MSY-GS30NA Model Item Total Capacity Unit Cooling Heating Cooling Heating Btu/h 30,700 32,600 32,000/33,200 35,200 SHF — 0.72 — 0.69 — Input kW 3.32 3.34 3.63/3.77 3.74 Rated frequency Hz 78 82 92 89 MSZ-GS30NA MSY-GS30NA Indoor unit Power supply Electrical circuit Input Fan motor current MSZ-GS36NA MSY-GS36NA V, phase, Hz 208/230, 1, 60 kW Cooling: 0.078 Heating: 0.055 A Cooling: 0.70/0.63 Heating: 0.52/0.
7-5. CAPACITY AND INPUT CORRECTION BY INVERTER OUTPUT FREQUENCY MUZ-GS30NA MUZ-GS30NAH MUY-GS30NA 1.5 1.0 0.5 0.0 0 25 50 75 100 (Hz) Correction of Cooling total input 1.5 Correction of Heating capacity 1.5 1.0 1.0 0.5 0.0 0 2.0 0.5 25 50 75 100 (Hz) 0.0 0 2.0 Input correction factors Input correction factors Capacity correction factors 2.0 Capacity correction factors Correction of Cooling capacity 2.
8 ACTUATOR CONTROL MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA 8-1. OUTDOOR FAN MOTOR CONTROL The fan motor turns ON/OFF, interlocking with the compressor. [ON] The fan motor turns ON 5 seconds before the compressor starts up. [OFF] The fan motor turns OFF 15 seconds after the compressor has stopped running. 5 seconds 15 seconds ON Compressor OFF ON Outdoor fan motor OFF 8-2. R.V. COIL CONTROL Heating. . . . . . . . . . . . . . . . . . ON Cooling . . . . . . . . . . . . . . . .
9 SERVICE FUNCTIONS MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA 9-1. CHANGE IN DEFROST SETTING Changing defrost finish temperature To change the defrost finish temperature, cut/solder the JS wire of the outdoor inverter P.C. board (Refer to 10-6.1.). Defrost finish temperature Jumper JS MUZ-GS30/36NA MUZ-GS30/36NAH MUY-GS30/36NA Soldered (Initial setting) 50°F (10°C) None (Cut) 64°F (18°C) 9-2.
10 TROUBLESHOOTING MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA 10-1. CAUTIONS ON TROUBLESHOOTING 1. Before troubleshooting, check the following 1) Check the power supply voltage. 2) Check the indoor/outdoor connecting wire for miswiring. 2.
10-2. FAILURE MODE RECALL FUNCTION Outline of the function This air conditioner can memorize the abnormal condition which has occurred once. Even though LED indication listed on the troubleshooting check table (10-3.) disappears, the memorized failure details can be recalled. 1. Flow chart of failure mode recall function for the indoor/outdoor unit Operational procedure The cause of abnormality cannot be found because the abnormality does not recur.
2. Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal. Check if outdoor unit is abnormal according to the following procedures. Make sure that the remote controller is set to the failure mode recall function. With the remote controller headed towards the indoor unit, press TEMP button to adjust the set temperature to 77°F (25°C). *1 Does the left lamp of the OPERATION INDICATOR lamp on the indoor unit blink at the interval of 0.
NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-3.). 3. Table of outdoor unit failure mode recall function The left lamp of the OPERATION INDICATOR lamp (Indoor unit) OFF 1-time blink 2.5 seconds OFF Abnormal point (Failure mode/protection) None (Normal) Indoor/outdoor communication, receiving error Indoor/outdoor communication, receiving error LED indication (Outdoor P.C. board) — — — 2-time blink 2.5 seconds OFF Outdoor power system 3-time blink 2.
NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-3.). The left lamp of the Abnormal point OPERATION (Failure mode/protection) INDICATOR lamp (Indoor unit) 10-time blink Discharge temperature 2.5 seconds OFF 11-time blink 2.5 seconds OFF 14-time blink 2.5 seconds OFF *1 16-time blink 2.5 seconds OFF *1 Bus-bar voltage (DC) Each phase current of compressor Stop valve (Closed valve) LED indication (Outdoor P.C. board) — 8-time blink 2.
10-3. TROUBLESHOOTING CHECK TABLE No. 1 Symptom Outdoor unit does not operate. Abnormal point/ Condition 1-time blink every Outdoor power sys2.5 seconds tem 3 5 6 Remedy • Reconnect connector of compressor. • Refer to 10-5. "How to check inverter/compressor". • Check stop valve. Outdoor thermistors Discharge temperature thermistor, fin temperature thermistor, • Refer to 10-5. "Check of outdoor defrost thermistor, P.C. board temperature thermistor, outdoor thermistors".
No. Symptom 16 Outdoor unit operates. LED indication 1-time blink 2.5 seconds OFF Outdoor unit operates. Current from power outlet is nearing breaker capacity. The unit is normal, but check the following. Check if indoor filters are clogged. • • Check if refrigerant is short. • Check if indoor/outdoor unit air circulation is short cycled. Frequency drop by defrosting in COOL mode Indoor coil thermistor reads 46°F (8°C) or less in COOL mode, compressor frequency lowers. 4-time blink 2.
10-4. TROUBLESHOOTING CRITERION OF MAIN PARTS MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA Part name Check method and criterion Defrost thermistor (RT61) Measure the resistance with a tester. Fin temperature thermistor (RT64) Figure Refer to 10-6. “Test point diagram and voltage”, 1. “Inverter P.C. board”, for the chart of thermistor.
10-5. TROUBLESHOOTING FLOW A How to check inverter/compressor Disconnect the connector between the compressor and the power module (IC700). See 10-5. Check the voltage between terminals. Are the voltages balanced? Yes No Replace the inverter P.C. board. See 10-5. Check the compressor. “Check of open phase”. “Check of compressor”.
D Check of compressor winding ●Disconnect the connector between the compressor and the power module (IC700), and measure the resistance between the compressor terminals. <> At 3 points BLK-WHT *Measure the resistance between the lead wires at 3 points. BLK-RED WHT-RED <> Refer to 10-4. 0 [Ω] ················Abnormal [short] Infinite [Ω] ·······Abnormal [open] NOTE: Be sure to zero the ohmmeter before measurement.
G Check of outdoor thermistors Disconnect the connector of thermistor in the inverter P.C. board (see below table), and measure the resistance of thermistor. Is the resistance of thermistor normal? (Refer to 10-6.1.) Yes No Replace the thermistor except RT64. When RT64 is abnormal, replace the inverter P.C. board. Reconnect the connector of thermistor. Turn ON the power supply and press the emergency operation switch.
H Check of R.V. coil MUZ-GS30/36 * First of all, measure the resistance of R.V. coil to check if the coil is defective. Refer to 10-4. * In case CN602 is disconnected or R.V. coil is open, voltage is generated between the terminal pins of the connector although no signal is being transmitted to R.V. coil. Check if CN602 is connected. Unit operates in COOL mode even if it is set to HEAT mode. Disconnect connector between the compressor and the power module (IC700).
I Check of outdoor fan motor Disconnect the connectors CN931 and CN932 from the inverter P.C. board. Check the connection between the connector CN931 and CN932. Is the resistance between each terminal of outdoor fan motor normal? (Refer to 10-4.) No Yes Disconnect CN932 from the inverter P.C. board, and turn on the power supply. Rotate the outdoor fan motor manually and measure the voltage of CN931.
J Check of power supply Disconnect the connector between the compressor and the power module (IC700). Turn ON power supply and press the emergency operation switch. Does the left lamp of the OPERATION INDICATOR lamp on the indoor unit light up? Yes Is there bus-bar voltage 260 - 370 V DC between 294 - 370 V DC between IC700 (P) and (N) on the inverter P.C. board? (Refer to 10-6.1.) No Check the electric parts in main circuit. Rectify indoor/outdoor connecting wire.
K Check of LEV (Expansion valve) Turn ON the power supply. While pressing both Operation select button and TEMP button on the remote controller at the same time, press RESET button. First, release RESET button. Hold down the other 2 buttons for another 3 seconds. Make sure that the indicators on the LCD screen shown in the right figure are all displayed. Then release the buttons.
L Check of inverter P.C. board Check the outdoor fan motor. (Refer to 10-5. .) Is the fuse (F901) blown on the inverter P.C. board? No Yes Check the connection of the connectors (CN931, CN932) of the outdoor fan motor. If the connection is poor, make it correct. Operate the outdoor unit by starting EMERGENCY OPERATION. Check the LED indication on the inverter P.C. board. Does the LED blink 10 times? Yes (10-time blink) No Check the corresponding parts following LED indication. (Refer to 10-3.
M How to check miswiring and serial signal error Turn OFF the power supply. Is there rated voltage AC in the power supply? Check the power supply. No Yes Turn ON the power supply. Is there rated voltage between outdoor terminal block S1 and S2? Yes Check the wiring. No Press the emergency operation switch once.
N Check of defrost heater MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA Check the following points before checking electric continuity. 1. Does the resistance of ambient temperature thermistor have the characteristics? Refer to 10-6.1. 2. Is the resistance of defrost heater normal? Refer to 10-4. 3. Does the heater protector remain conducted (not open)? 4.
P Electromagnetic noise enters into TV sets or radios Is the unit grounded? Yes Is the distance between the antennas and the indoor unit within 9.91 ft. (3m), or is the distance between the antennas and the outdoor unit within 9.91 ft. (3m)? No Is the distance between the TV sets or radios and the indoor unit within 3.28 ft. (1m), or is the distance between the TV sets or radios and the outdoor unit within 9.91 ft. (3m)? Ground the unit.
10-6. TEST POINT DIAGRAM AND VOLTAGE 1. Inverter P.C. board MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA Back side of unit Smoothing Capacitor (CB1) Smoothing Capacitor (CB2) Smoothing Fuse (F880) Output to drive Capacitor T3.15AL250V outdoor fan motor (CB3) (CN932) Heater (CN601) 208/230 V AC [MUZ-GS30/36NAH] 208/230 V AC R.V. coil/ 21S4 (CN602) 208/230 V AC Fuse (F62) 15 A 250 V LED Fuse (F901) T3.
11 DISASSEMBLY INSTRUCTIONS The terminal which has the locking mechanism can be detached as shown below. There are 2 types of the terminal with locking mechanism. The terminal without locking mechanism can be detached by pulling it out. Check the shape of the terminal before detaching. (1) Slide the sleeve and check if there is a locking lever or not. (2) The terminal with the connector shown below has the locking mechanism.
OPERATING PROCEDURE PHOTOS/FIGURES 2. Removing the inverter assembly and inverter P.C. board (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the lead wire to the reactor and the following connectors: CN602 (R.V.
OPERATING PROCEDURE PHOTOS/FIGURES * Connection procedure when attaching the inverter P.C. board (Photo 8, 9) Photo 7 1. Attach the heat sink support to the P.C. board support. 2. Hook the lead wires of the compressor, the reactor and the P.C. board to each hooks on the heat sink support as shown Photo 8. 3. Connect the lead wires of the expansion valve coil to the connector on the inverter P.C. board. Pull the lead wires of the expansion valve coil toward you and put them on the left hook on the P.C.
OPERATING PROCEDURE PHOTOS/FIGURES 3. Removing the discharge temperature thermistor, defrost thermistor, outdoor heat exchanger temperature thermistor and ambient temperature thermistor Photo 10 Outdoor heat exchanger temperature thermistor (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the lead wire to the reactor and the following connectors:
OPERATING PROCEDURE PHOTOS/FIGURES 5. Removing the compressor and 4-way valve (1) Remove the top panel, cabinet and service panel. (Refer to section 1.) (2) Remove the back panel. (Refer to section 1.) (3) Remove the inverter assembly. (Refer to section 2.) (4) Recover gas from the refrigerant circuit. NOTE: Recover gas from the pipes until the pressure gauge shows 0 PSIG. (5) Detach the brazed part of the suction and the discharge pipe connected with compressor. (6) Remove the compressor nuts.
