Cooling Operation; Auto Operation; Dry Operation - Carrier 42cvur018-703 Service Manual

Item
Operation flow and applicable data, etc.
1. Basic

2. Cooling operation

operation
The operations are performed in the following parts by controls according to cooling conditions.
1) Receiving the operation ON signal of the remote controller, the cooling operation signal
starts being transferred form the indoor controller to the outdoor unit.
2) At the indoor unit side, the indoor fan is operated according to the contents of "2. Indoor fan
motor control" and the louver according to the contents of "7. Louver control", respectively.
3) The outdoor unit controls the outdoor fan motor, compressor and pulse Modulating valve
according to the operation signal sent from the indoor unit.
Operation ON
Indoor unit control
Sending of operation command signal
Outdoor unit control

3. AUTO operation

One of 2 operations (Cooling or Fan only) is selected according to difference between the preset
temperature and the room temperature at which the automatic operation has started, as shown in
follow figure. The Fan only operation continues unit the room temperature reaches a level at which
another mode is selected.
*1. When reselecting the operation mode, the fan
speed is controlled by the previous operation mode.

4. DRY operation

DRY operation is performed according to the difference
between room temperature and the setup temperature as
shown below.
In DRY operation, fan speed is controlled in order to
prevent lowering of the room temperature and to avoid air
flow from blowing directly to persons.
[ ˚C ]
Ta
+ 1.0
+ 0.5
Tsc
Setup of remote controller
Indoor fan motor control / Louver control / Operation Hz
Compressor revolution control / Outdoor fan motor control /
Ta
Cooling operation
Ts + 1
Monitoring (Fan)
Control (Requierment)
Operation Hz control (Include limit control)
Pulse Modulating valve control
1) Detects the room temperature (Ta) when
2) Starts operation under conditions in the
3) When the room temperature is lower
L– (W5)
(W5+W3) / 2
SUL (W3)
Fan speed
− −
26
FILE NO. SVM-12052
Description
the DRY operation started.
left figure according to the temperature
difference between the room tempera-
ture and the setup temperature (Tsc).
Setup temperature (Tsc)
= Set temperature on remote controller
(Ts) + (0.0 to 1.0)
1°C or less than the setup temperature,
turn off the compressor.