York YHKMXH009BARX-FX Service Manual page 216

2.2 Indoor unit function
2.2.1 Sign definition
Indoor
Tai Tc1 Tc2 Tm
Outlet Inlet
mid coil
Ambient pipe pipe
temp
temp temp. temp
Tcomp1,2 Tset
Set
Temp. compensation
temp.
2.2.2 Dry operation
o
Tai ＜ 16 C, indoor unit stops running and sends stop-unit signal to outdoor.
Tai≤Tset, indoor motor runs at low speed and sends stop-unit signal to outdoor
2.2.3 Fan operation
Indoor fan motor will run as the fan speed set on the remote controller or the wired controller and indoor unit
will send the stop-unit signal to outdoor.
2.2.4 Auto operation
A: If the unit enters Auto mode for the first time, the system will adjust the operation mode according to the
room temp. and the set temp.
When Tai≥Tset, entering auto cooling mode;
When Tai ＜ Tset, entering auto heating mode.
B: Auto cooling mode is as the same as the cooling mode. After the thermostat is OFF for 15 minutes, if Tai+
1+Tcomp2 ＜ Tset, the unit will enter auto heating mode, or the unit will still stay at auto cooling mode and stop
when it reaches the set temperature; while the indoor motor will be at low speed.
C: Auto heating mode is as the same as the heating mode. After the thermostat is OFF for 15 minutes, if
Tai≥Tset+1 +Tcomp1, the unit will enter auto cooling mode, or the unit will still stay at auto heating mode;
D: In this mode, the Sleep function is available, run as cooling sleep in cooling mode and as heating sleep in
heating mode. Once sleep mode is set, the mode will not change after the unit stops for 15 minutes when it
arrives Tset.
E: Mode conversion will be confirmed after compressor has stopped for 10 minutes.
2.2.5 Abnormal operation
A: When outdoor modes from the request of indoor unit conflict, the one entering firstly will take priority.
B: After indoor receives the ON command from wired controller, it will firstly confirm the outdoor current
operation mode. If they are the same modes, indoor unit will run as the request of remote controller. If they are
different modes, the system will forbid to operate, and indoor will keep the OFF mode and send the "standby"
signal to wired controller until outdoor stops or outdoor mode the requested mode of wired controller are the
same, the unit will run as the requested mode of wired controller.
C: After indoor receives the ON command from remote controller, it will firstly confirm the outdoor current
operation mode. If they are the same mode, indoor unit will run as the request of remote controller. If they are
different modes, the system will forbid to operate, and indoor will keep the OFF mode. After setting on remote
controller, if the buzzer sounds two times, that shows abnormal operation. Indoor will run until the outdoor mode
and the requested mode of remote controller are the same.
D: In AUTO mode, when the indoor unit occurs abnormal operation, the indoor unit will keep OFF state, and the
buzzer will not sound until the outdoor mode and the requested mode of indoor unit are the same.
F: COOL (included AUTO COOL), DRY, FAN are not abnormal mode.
G: HEAT and FAN are not abnormal mode.
Tao Toci Tc
Thick pipe mid
Ambient of heat condenser
temp exchanger temp.
outdoor
Te Ts Td
Compressor Compressor
Defrost suction discharging
temp temp. temp.
214