York YKHC 18, Service Manual

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3.4 Cooling Mode
3.4.1 Four-way valve is closed. If four-way valve is open before the mechine enters cooling mode, then four-way
valve will be closed at the first time the compressor starts under the cooling mode.
3.4.2 Conditions for the compressor and outdoor fan action (Ts = set temperature, Ta=room temperature)
Condition Compressor Outdoor fan
Ta > Ts+1 On On Room temp. up
Ta <Ts+1 Off Off
Ta > Ts On On Room temp. down
Ta <Ts Off Off
3.4.3 Action of Indoor Fan
3.4.3.1 HIGH/LOW/AUTO fan can be switched over for your comfort.
3.4.3.2 Auto fan under cooling mode.
Condition (T=Indoor Temp.-Setting Temp.) Indoor fan speed
T<4°C Low Temp. up
T>4°C High
T> 1°C High
Temp. down
T<1°C Low
3.5 Dehumidifying Mode
3.5.1 Dehumidifying mode is the cooling operation, under which the indoor fan is high and outdoor fan is low.
3.5.2 Protective condition is actived.
3.6 Auto Mode
3.6.1 Under auto mode, the indoor fan is set to be auto (refer to auto fan under cooling, heating).
3.6.2 When entering auto mode, the heating, fan only or cooling operation will be automatically chosen according
to the room temperature Ta and the set temperature Ts.
3.6.2.1 When Ta < Ts - 1°c, it performs the heating operation with a set temperature of Ts - 1°c (refer to the
heating mode). However the cool only model will be in low fan.
3.6.2.2 When Ts + 2°c Ta Ts - 1°c, control according to cooling auto fan with a set temperature of
23°c.
3.6.2.3 When Ta > Ts +2°c, it performs the cooling operation with a set temperature of Ts (refer to the cooling
mode).
3.6.3 After one mode is chosen, if the condition Ta > Ts+1°c or Ta < Ts - 1°c lasts for 15 minutes, meanwhile the
compressor doesn't start up within consecutive 15 minutes, the operation mode will be re-chosen according
to the Ta and Ts.
3.6.4 Protective condition is actived.
3.7 Fan Only Mode
3.7.1 Under this mode, four-way valve, compressor and outdoor fan are shut down.
3.7.2 High/Low/Auto fan can be switched over through manual control. Auto fan will be controlled in line with
cooling auto fan with temperature set to be 23°C.
3.7.3 After entering fan mode, the operating indicator is on. If the model is cooling only mode, fan indicator is on
at the same time.