MovinCool Climate Pro 18 Service Manual - Manual (Page 34)

Operation Section
34
5.2 Basic Operation of Electrical Circuit
• There are two basic components used to control the operation of electrical system:
- Control panel assembly
- Service box
• The control panel assembly contains the display panel and keypad. The service box contains all
input and output devices such as temperature devices, sensors, relays, switches and
microprocessor.
(1) Fan Only mode
• Fan Only mode can be selected by pressing the MODE button on the control panel and
confirming to start the operation of Fan Only mode. In this mode, the fan relay RL02 is closed
and the fan speed relays are either closed or opened depending on fan speed setting. When fan
Hi speed is set, the relay RL03 terminal 4 and the relay RL04 terminal 4 are closed. When fan
Mid speed is set, the relay RL03 terminal 3 and the relay RL04 terminal 4 are closed. When fan
Lo speed is set, the relay RL04 terminal 3 is closed.
(2) Cool mode
• Cool mode can be selected by pressing the MODE button on the control panel and confirming
to start the operation of Cool mode. In this mode, the indoor fan relays RL02, RL03, and RL04
are operated based on fan speed setting, and the outdoor fan relay RL09 and the compressor
relay RL01 are operated after the 120 seconds time delay has been expired.
(3) Heat mode
• Heat mode can be selected by pressing the MODE button on the control panel and confirming
to start the operation of Heat mode. In this mode, the 4-way valve relay RL06 and the indoor fan
relays RL02, RL03, and RL04 are operated based on fan speed setting. The outdoor fan relay
RL09 and the compressor relay RL01 are operated after the 120 seconds time delay has been
expired. During Heat mode, the heater relay RL08 is closed when the ODS (outdoor air inlet
thermistor) detects below 24 °F (-4 °C) to prevent the drain pan from freezing and opened when
the ODS detects above 43 °F (6 °C).