iAIRE, LLC
SHVAC
Residential Mini-Split and Mounting Kit I/O/M
44
Electronic Controller Information
Air Conditioner Service Manual
11
5.2 Electronic controller
RT-------Room Temperature.
IPT------Indoor Pipe (Coil) Temperature.
ST------Indoor Setting Temperature.
OPT---Outdoor Pipe Temperature.
OAT---Outdoor Ambient Temperature.
ODT---Outdoor Discharge Temperature.
CRT---Compensated Room Temperature.
IDU--- Indoor unit
ODU---Outdoor unit.
Note:
When AC finishing installation, because of the air ventilation and the distance of temperature test sensor to
different location of the house, the temperature for IDU PCB control need compensation.
1
）
）
. Cooling mode. CRT=RT;
2
）
）
. Heating mode. CRT=RT-3
℃
(5.4
℉
)
-----Split AC.
5.2.1 Auto mode
5.2.1.1. The set temperature can be adjusted from 16-31
℃
(60.8-87.8
℉
)
on auto mode, the operation of fan speed and
vane position according to preset.
5.2.1.2. Operation
When unit set to auto mode, it will work on cooling, heating or fan mode totally according to Δt
--the temperature
difference between RT and ST shown as table:
Mode
Δt=RT-ST
COOLING
Δt >1
℃
℃
(1.8
℉
℉
)
FAN
-1
℃
℃
(-1.8
℉
℉
)≤Δt≤ 1
℃
℃（
（
1.8
℉
℉）
）
HEATING
Δt <-1
℃
℃（
（
-1.8
℉
℉）
）
5.2.2 Cooling mode
5.2.2.1. Temperature control :16-31
℃
(60.8-87.8
℉
)
, and the operation of fan speed and vane position according to preset.
5.2.2.2. Compressor and process control
1). When RT-
ST≥0.5
℃
(0.9
℉
)
, the compressor starts up working, AC operates as customer preset;
2). When
a. RT-
ST≤
－
3
℃
(-5.4
℉
)
and compressor keeps 2 min continuously; or
b. RT-
ST≤
－
2
℃
(-3.6
℉
)
and compressor works in lowest frequency for 5 min continuously; or
c. RT-
ST≤
－
1
℃
(-1.8
℉
)
and compressor works in lowest frequency for 10 min continuously,
The compressor stops operation.
3). The compressor frequency control: Based on relation of RT & ST, and the changing speed of RT.
4). The compressor will also stop working while unit:
a. switched off.
b. under protection.
c. changed to fan mode.
5). Under normal operation, the compressor can be stopped by program only working after 7 min once it starts up.
6). In the process of unit operation, once the compressor ceased, it should be 3 min delay for the next procedure.
5.2.2.3. ODU Fan motor control:
1). While unit:
a. switched off.
b. under protection.
c. to the set temperature.
After compressor ceased, the fan motor stops working according to the temperature of OPT and OAT, the max
