14
4.2.7
H
EAT EXCHANGER PARAMETERS
The
ELIM
parameter specifies the minimum allowed temperature on the heat exchanger outlet. When
the temperature is below this threshold, the heat exchanger alarm is switched on, the air supply fan is
switched off and the system starts the heat exchanger defrosting cycle.
Name
Default
value
Range
Description
ELIM
5
C
-
10 ÷ +10
C Alarm temperature for the heat exchanger
4.2.8
E
XCHANGER DEFROST
Defrosting the exchanger is done by running the extract fan at the highest speed for a period of two to
five minutes (depending on the outside temperature), while the inlet fan is stopped. After the defrost
time has elapsed, the extract fan returns to the programmed speed for 20 minutes and the inlet fan
remains off unless the frost alarm goes off.
If after 20 minutes the heat exchanger temperature is still lower than the alarm level, the defrost
procedure will be restarted.
The defrosting procedure ends when the temperature at the exchanger outlet rises above the alarm
level.
The curve representing the defrost time as a function of the outdoor temperature:
Outdoor temperature
Defrost time
-10C
5 min
-5C
2 min
