Defrost
Function
The defrost control activated only in
the "HEAT" mode to de-ice the outdoor coil.
The defrost controller is of the time and temperature type as
indicated in the process below.
- If the temperature increases above 3 ºC for more than
2 minutes, the defrost controller is deactivated and the time
is reset.
- When the temperature decreases below 3 ºC, the defrost
controller is activated and the
timer starts counting the time period to use it with the outdoor
coil temperature in determining when to start the process as
follows :
• Should the outdoor coil sensor temperature be <=
- 8 ºC for a time period of 30 minutes.
• Should the outdoor coil sensor temperature be <=
- 4 ºC for a time period of 1 hour.
• Should the outdoor coil sensor temperature be <=
- 2 ºC for a time period of 2 hours.
After either one of the
three above cases, the operating mode will change to "COOL"
and the microprocessor of the PC-board will stop both the indoor
and the outdoor fans.
The defrost Cycle is complete when the outdoor coil temperature
sensor reads 10 ºC or after de-icing period of 10 minutes
whichever is first.
When the defrost cycle is completed, the operating mode will
re-change to "HEAT".
