If the return water tem-
perature does the fol-
lowing within a five-mi-
nute period
and total
number of
restarts
Response
Remains below the con-
stant heating temperature
> 0
5 min: After 5 minutes, the MVM
valve will close and the CP will stop.
The alarm must be reset manually in
menu 4.
∞
: MVM valve 100% open and cir-
culation pump continues operation.
NB
The frost protection function is only active when the outdoor air temperature is be-
low 10°C.
Menu 7.3 - Frost protection heat exchanger
7.3 Frost protection HR
De-icing temp. >
No. of restarts >
Time ext. [min]
°c
0.0
10
0
The de-icing icon is displayed in the user menu every time the unit operates
de-icing.
T
ice
Select from the menu the temperature at which de-icing is activated.
Recommended de-
icing, T
ice
Home: T
ice
= 0
℃
Office/school: T
ice
= -5
℃
Fine adjustment of
T
ice
As ice formation in the counter flow heat exchanger is strongly dependent on the
humidity content of the extract air, the air temperatures and the air volumes, it is
recommended that the unit is fine-adjusted once it has been brought into use.
Fine adjustment of T
ice
can reduce annual energy consumption.
How to carry out
fine adjustment
Check whether ice is present when the
icon appears in the display. If no ice
is apparent when the icon appears, T
ice
can advantageously be lowered by 1K.
The unit must be monitored for a period and ice checks in the heat exchanger reg-
ularly made. Once T
ice
has been reduced to the optimum for the building/condi-
tions, there will be ice present when the
icon appears.
Alarm 32024
If the unit displays alarm no. 32024 "Frozen counter flow heat exchanger", T
ice
must be increased by 1K-2K.
3006401-2022-05-04
Starting up the unit for operation
39/72
Summary of Contents for EXact2 HMI2-350-TOUCH
Page 72: ......
