11-7
CONTROL SYSTEM
SM YAZDCI 1-A.1 GB
11.4.3 Heat
Mode
NLOAD is calculated according to the difference between actual room temperature and user
set point temperature by PI control.
In high/ medium/ low indoor fan user setting, unit will operate fan in selected speed.
In AutoFan user setting, fan speed will be adjusted automatically according to the calculated
NLOAD.
11.4.3.1
Temperature Compensation
In wall mounted, ducted, and cassette models, 3 degrees are reduced from room
temperature reading (except when in I-Feel mode), to compensate for temperature
difference between high and low areas in the heated room, and for coil heat radiation on
room thermistor.
The temperature compensation can be enabled/disabled by shortening of J2 on the indoor
unit controller.
Model
J2 Shorted
J2 Opened
Wall mounted
Compensation Disabled
Compensation Enabled
Cassette
Compensation Enabled
Compensation Disabled
Ducted
Compensation Enabled
Compensation Disabled
Floor/Ceiling
Compensation Disabled
Compensation Enabled
11.4.3.2
Indoor Fan Control in Heat Mode
Indoor fan speed depends on the indoor coil temperature:
ICTST ICTVL ICTL ICTH ICTT
11.4.4
Auto Cool/Heat Mode
When in auto cool heat mode unit will automatically select between cool and heat mode
according to the difference between actual room temperature and user set point temperature
(
Δ
T).
Unit will switch from cool to heat when compressor is off for 3 minutes, and
Δ
T < -3.
Unit will switch from heat to cool when compressor is off for 5 minutes, and
Δ
T < -3.
11.4.5 Dry
Mode
As long as room temperature is higher then the set point, indoor fan will work in low speed
and compressor will work between 0 and
MaxNLOADIF1C
Hz.
When the room temperature is lower than the set point, compressor will be switched OFF and
indoor fan will cycle 3 minutes OFF, 1 minute ON.
