Haier HSU09VHG(DB)-W Service Manual

Also see for 1U09ES2VHA: Installation manual

Contents

SEQUENCE OF OPERATIONPAGE 29ENGLISHThe outdoor unit main board also controls the position of theEEV (Electronic Expansion Valve)to regulate the flow of refrigerant to the indoor unit evapora-tor coil.Temperature sensorsFour temperature sensors located in the outdoor unit providetemperature information to the outdoor unit main board forcontrol of the system during cool mode.The outdoor ambient temperature sensor provides thetemperature of the air drawn into the condenser coil of theoutdoor unit.The defrost temperature sensor provides the temperaturesensed at the output of the condenser coil.The suction line temperature sensor provides the tempera-ture sensed at the incoming suction line pipe.The compressor discharge sensor provides the temperaturesensed at the discharge pipe of the compressor.Call to Terminate CoolingThe system will call to terminate cooling when the indoor am-bient temperature sensor is equal to or lower than 2°F of theroom set temperature. The indoor control board will com-municate to the outdoor control board to de-energize thecompressor. The outdoor fan will run for 60 seconds beforestopping.The indoor fan motor and louver will continue operating aftercooling has been terminated.To stop cool mode, press the power button to turn the sys-tem off, or change to another mode.Freeze protection functionTo prevent freezing of the indoor unit coil during cool mode,when the compressor operates continuously for 10 secondsand the temperature of the indoor coil has been below 32°Ffor 10 seconds, the compressor will stop, and the error willbe recorded in the malfunction list. The indoor unit fan willcontinue to operate. When the temperature of the indoor coilrises to 45°F for more than 3 minutes the compressor willrestart and the system will continue functioning.Heat ModeOverviewThe temperature control range in heating mode is 60°F - 86°F.The temperature set by the remote control and the indoorunit ambient temperature sensor will determine if a call forheat is needed. If a call for heat is justified, a temperaturecompensation adjustment is automatically added to theoperating parameter and the call is communicated from theindoor unit to the outdoor unit.The indoor unit louver will open using a stepper motor. Theindoor fan will not operate at this time.The outdoor unit will shift the 4-way valve to the heat modeposition and determine the position of the EEV (if equipped)and speed (frequency) of the compressor. There can be adelay of up to 3 minutes before the outdoor unit fan and com-pressor start.(Tr = room temperature Ts = set temperature)If Tr ≤ Ts, the outdoor unit will operate and the indoor fanoperates in cold air prevention functionIf Tr > Ts+, the outdoor unit turns off and the indoor fan oper-ates at heat residue sending mode.If Tr < Ts+, the outdoor unit will restart and the indoor fanoperates in cold air proof mode.The speed of the indoor fan can be controlled manually bythe user or automatically by the system. The speed can bechanged between HIGH, MEDIUM, and LOW. The predeter-mined conditions for automatic control are as follows:High Speed: Tr < TsMedium Speed: Ts ≤ Tr ≤ Ts + 4°FLow Speed: Tr > Ts + 4°FWhen the indoor fan is running in automatic mode and thereis no delay when the speed switches from high to low, theindoor fan will maintain high speed for a period of 3 minutesbefore switching to low speed.Cold air proof operationAt initial start of heat mode, indoor blower will not be turnedon immediately until indoor coil temperature senses a mini-mum temperature. This period usually takes 30 seconds to 3minutes depending on the outdoor ambient temperature.HSU12 HG(DB)-SM Wiring Diagrams*Indoor fan controlmanual control: You can choose high, medium, low and automatic speed control.Automatic: When TrWhen Ts≤Tr≤Ts+2 ć, medium speed.When Tr> Ts+2 ć, low speed.When the airflow speed has no delay from the high to low switching, the speed should be de3 minutes (remain at high speed for 3 minutes.) before the next switch.*Airgate location control: the location for the airgate can be set according to your needs.Coldair proof operation1. The indoor operation within 4 minutes after the start up is as the following diagram, thecan be raised only after the speed has reached a certain level.2. 4 minutes after the start up of the indoor fan, the light airflow and the low airflow will be turnset speed airflow.3. In the cold air proof operation, the fan won’t stop after the start up.4. During the cold air proof operation, the indoor system will continuously send ‘indoor hisignals to the outdoor system.* Residue heat sending. The indoor fan will send the residue heat at a low speed for 12 secoIf other conditions are satisified, when the compressor stops, the indoor system will operatespeed. The indoor fan will stop when the coil temperature is below the ‘heat start temp 4’.* Defrosting. When the system receives the defrosting signal from outdoors, the indoor fanand the indoor temperature display won’t change. At the time, any indoor coil malfunctioneglected. When the outdoor defrosting finishes, the coil malfunction will still be neglectedcompressor has been started up for 30 seconds. The indoor temperature display will not chthe system operates at the cold air proof mode.* Automatic heating temperature compensation: when the system enters the heating mtemperature compensation (4) will be added. When the status is switched off, the compenbe erased.Heat start temp 1Heat start temp 2Heat start temp 3Heat start temp 4Set speedLow speedLight speedFan/offFan/offKeep the highspeed. The fandoesn’t stop4 minutes after the indoor fan starts, the light or low speedwill switch to the set speed.In cold air proof operation, the fan remains on after startup.Residual heat sending: the indoor fan will operate on lowspeed for 12 seconds.The outdoor unit temperature sensors: outdoor ambient,defrost, suction line, and compressor discharge, used inconjunction with the indoor temperature sensors, indoor