Airwell YFAD-100R-01M25, Technical Manual

Page: 59 / 96

 Page 59 
1. Operation Modes and Functions
1.1 Abbreviation
Unit element abbreviations
Abbreviation Element
T1 Indoor room temperature
T2 Coil temperature of evaporator
T3 Coil temperature of condenser
T4 Outdoor ambient temperature
T5 Compressor discharge temperature
1.2 Safety Features
Compressor three-minute delay at restart
Compressor functions are delayed for up to one minute
upon the first startup of the unit, and are delayed for up
to three minutes upon subsequent unit restarts.
Phase Check Function(for 3 phase models)
If the phase sequence is detected wrong or lack of 1
or 2 phase, the unit won’t start and there is error code
displayed on outdoor PCB.
Low Pressure Check Function(For 36K~60K)
The low pressure switch should be always closed. If it is
open, the system will stop until the fault is cleared. During
defrosting procedure , 4 minutes after defrosting ends and
5 minutes after compressor is on in heating mode, low
pressure switch won’t be checked.
Note: The system will not check if the protection could be
cleared in 30 seconds after the protection occurs. If this
protection occurs 3 times, it won’t recover automatically
until the main power is cut off.
Over-current protection
When compressor is running, if the current is over twice
of the rated for 3 seconds, the compressor will stop and
an error code will be displayed on the outdoor PCB. If the
current becomes normal, the indoor sends signal to the
outdoor, the outdoor will display normally.
Open Circuit/Disconnection Sensor Protection
1.3 Display Function
Unit display functions
1.4 Fan
When fan mode is activated:
• The outdoor fan and compressor are stopped.
• Temperature control is disabled and no temperature
setting is displayed.
• The indoor fan speed can be set to high, medium, low,
or auto.
• The louver operations are identical to those in cooling
mode.
1.5 Cooling Mode
1.5.1 Compressor Control
• When T1-Ts-
∆
T is lower than setting value, the
compressor ceases operation.
• When T1-Ts-
∆
T is higher than setting value, the
compressor continues operation.
1.5.2 Indoor Fan Control
• In cooling mode, the indoor fan operates continuously.
The fan speed can be set to high, medium, low or
auto..
• The auto fan acts according to the value of T1-
TS+
∆
T1.
1.5.3 Outdoor Fan Control
• For single-fan outdoor units, the outdoor fan will
run following the compressor except when AC is in
evaporator high temperature protection in heating
mode ,condenser high temperature protection in
cooling mode, defrosting mode and the current
protection.
• For double-fan units, the outdoor fans will run
according to T3.
1.5.4 Evaporator Temperature Protection
When evaporator temperature drops below a configured
value for some time, the compressor ceases operations.
Pr
oduct Featur
es