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Cover Service manual Service manual Service manual Service manual Room airconditioner Room airconditioner Room airconditioner Room airconditioner Split Wall mounted Type Split Wall mounted Type Split Wall mounted Type Split Wall mounted Type MSH-21HRN1-QB8 MSH-24HRN1-QB8 Applied to:...
Content Content Precaution............................2 Safety Precaution..........................2 Warning ..............................2 Function ..............................3 Dimension............................5 Indoor unit ............................5 Outdoor unit ............................5 Refrigerant cycle diagram.........................8 Operation limits..........................9 Cooling operation ..........................9 Heating operation..........................9 Wiring diagram ...........................9 Installation details ..........................10 Wrench torque sheet for installation ....................10 Connecting the cables ........................10 Pipe length and the elevation......................10 Air purging of the piping and indoor unit ....................11 Pumping down (Re-installation) ......................12...
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Content Troubleshooting ..........................27 10.1 Display board .............................27 10.2 Troubleshooting ..........................27 10.3 Diagnostic chart..........................28 10.4 Resetting phenomenon often occurs during operation ..............29 10.5 Operation lamp flashes and Timer lamp off ..................29 10.6 Operation lamp flashes and Timer lamp on ..................29 10.7 Operation lamp off and Timer lamp flashes ..................30 10.8...
Service manual 1. Precaution 1.1 Safety Precaution To prevent injury to the user or other people and property damage, the following instructions must be followed. Incorrect operation due to ignoring instruction will cause harm or damage. Before service unit, be sure to read this service manual at first. 1.2 Warning Installation Do not use a defective or underrated circuit...
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Service manual electric shock. Operational Do not open the inlet grill of the product during operation. (Do not touch the electrostatic Do not expose the skin directly to cool air for filter, if the unit is so equipped.) long periods of time. (Do not sit in the draft). There is risk of physical injury, electric shock, or product This could harm to your health.
Service manual 2. Function Indoor unit Operation ON/OFF by remote controller Sensing by room temperature Room temperature sensor. Pipe temperature sensor. Starting temperature control Indoor fan is delayed for 5 sec at the starting. Time Delay Safety control Restarting is for approx. 3 minutes..
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Service manual Outdoor unit Power relay control The unit has 3 mins delay between continuously ON/OFF operations. Low noise air flow system Bird tail propeller fan makes the outdoor unit run more quietly. Hydrophilic aluminum fin The hydrophilic fin can improve the heating efficiency at operation mode. 4 way valve control It is only operated in the heating operation mode except defrosting operation.
Service manual 5. Operation limits 5.1 Cooling operation Outdoor unit air temp.℃ DB Indoor air temp. ℃ DB Note: The chart is the result from the continuous operation under constant air temperature conditions. However, excludes the initial pull-down stage. 5.2 Heating operation Indoor air temp.
Service manual 7. Installation details 7.1 Wrench torque sheet for installation Outside diameter Torque inch Kg.m φ9.52 φ12.7 φ15.88 7.2 Connecting the cables The power cord of connect should be selected according to the following specifications sheet. Grade Unit 7.3 Pipe length and the elevation Standard Max.
Service manual 7.4 Air purging of the piping and indoor unit Required tools: Hexagonal wrench; adjustable wrench; torque wrenches, wrench to hold the joints and gas leak detector. Note: The air in the indoor unit and in the piping must be purged. If air remains in the refrigeration piping, it will affect the compressor, reduce the cooling capacity, and could lead to a malfunction of unit.
Service manual 7.5 Pumping down (Re-installation) Procedure Confirm that both the 2-way and 3-way valves are set to the opened position. Remove the valve stem caps and confirm that the valve stems are in the opened position. Be sure to use a hexagonal wrench to operate the valve stems. Operate the unit for 10 to 15 minutes.
Service manual 7.6 Re-air purging (Re-installation) Procedure: Confirm that both the 2-way and 3-way valves are set to the closed position. Connect the charge set and a charging cylinder to the service port of the 3-way valve. Leave the valve on the charging cylinder closed. Air purging.
Service manual 7.7 Balance refrigerant of the 2-way, 3-way valves Procedure: Confirm that both the 2-way and 3-way valves are set to the open position. Connect the charge set to the 3-way valve’s service port. Leave the valve on the charge set closed. Connect the charge hose with the push pin to the service port.
Service manual 7.8 Evacuation Procedure: Connect the vacuum pump to the charge set’s centre hose. Evacuation for approximately one hour. Confirm that the gauge needle has moved toward -0.1 Mpa (-76 cmHg) [vacuum of 4 mmHg or less]. Close the valve (Low side) on the charge set, turn off the vacuum pump, and confirm that the gauge needle does not move (approximately 5 minutes after turning off the vacuum pump).
Service manual 7.9 Gas charging Procedure: 1. Connect the charge hose to the charging cylinder. Connect the charge hose which you disconnected from the vacuum pump to the valve at the bottom of the cylinder. 2. Purge the air from the charge hose. Open the valve at the bottom of the cylinder and press the check valve on the charge set to purge the air (be careful of the liquid refrigerant).
Service manual 8. Electronic function 8.1 Electronic control working environment Input voltage: 175~253V or 100~130V Input power frequency: 60Hz Ambient temperature: -7°C+43°C Indoor fan normal working amp is less than 1A Outdoor fan normal working amp is less than 1.5A Four-way valve normal working amp is less than 1A Swing motor: DC12V Compressor: single-phase power supply.
Service manual 8.4 Protection 8.4.1 3 minutes delay at restart for compressor. 8.4.2 Sensor protection at open circuit and breaking disconnection 8.4.3 Fan Speed is out of control. When Indoor Fan Speed is too high(higher than High Fan+300RPM)or too low(lower than 400RPM), the unit stops and LED displays failure information and can’t returns to normal operation automatically.
Service manual Auto fan at cooling mode: High fan Mid. fan Room temp. down Room temp. up Low fan T-Ts Anti-freezing control to indoor evaporator at cooling mode ( T: evaporator temp. ) Compressor and outdoor fan on EVAP. temp. down EVAP.
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Service manual 8.8.3 Action of compressor and outdoor fan motor at heating mode: compressor must run for 7 minutes after starting and then judge temperature. Meanwhile other protections are still valid. Compressor and outdoor fan off Room temp. down Room temp. up Compressor and outdoor fan on Ts+2*...
Service manual Compressor off Fan off Compressor on Fan off T temp. down T temp. up Compressor on Fan on The louver opens to Standard Angle ANGLHEAT when power is on for the first time 8.9 Defrosting mode(available for heating mode) 8.9.1 Defrosting condition: Defrost starts when either of the following: The compressor works under the condition that T3 lower than 0’C add up to more than 40 minutes, and under...
Service manual Heating (fan only at cooling) Fan only Cooling TA-TS 8.10.2 The indoor fan blows automatically in corresponding selected mode; 8.10.3 The motion of indoor fan’s blade should accord with the selected operation mode; 8.10.4 One mode should be carried out for at least 15 minutes once selected. If the compressor cannot start for 15 minutes, reselect the operation mode according to the room temp.
Service manual The set temperature decrease 1℃ per hour. Two hours later, the set temperature will maintain as a constant and the air circulation is kept at low speed (Anti-cold function takes precedence over all). Room temperature Time 8.12.4 Auto: After an hour running under economic mode, the set temp will rise 1℃, if it is under cooling mode;...
Service manual Troubleshooting 10.1 Display board Operation The indicator flashes once every second after power is on and illuminates when the air conditioner is in operation. Timer indicator: The indicator illuminates then TIMER is set ON. PRE-DEF. indicator (For cooling & heating mode only) The air conditioner starts defrosting automatically if outdoor unit frosts in heating operating.
Service manual 10.3 Diagnostic chart After energizing, no indicator is lighted and the air conditioner can’t be operated. After energizing , the air conditioner can not be operated . Check if AC 220V power supply outputs to indoor PCB . Check if AC 220V exists at the primary coil of transformer.
Service manual 10.4 Resetting phenomenon often occurs during operation. (That is automatically entering to the status when power is on.) The reason is that the instantaneous voltage of main chip is less than 4.5V. Check according to the following procedure: Resetting phenomenon often occurs during operation .
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Service manual 10.6 Temperature sensor error. Including the indoor room, indoor evaporator and outdoor condenser temperature sensor. Is connector connection good ? Repair the connector . Replace the sencor , 10.7 Outdoor unit protects Check if the power supply is good Power supply failure Change outdoor PCB and check if the error is still exit Outdoor PCB failure...
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