3.2.3 Frost protection via electric pre-heating exchanger (optional)
The Series LG 1400 and LG 3200 ventilating unit may optionally be fitted with an electric pre-heating exchanger
to protect the heat exchanger from freezing. The cold outside air will to this end be pre-heated via a shell and
tube heat exchanger mounted directly in the outside air duct to counter freezing of the heat exchanger.
To reduce the consumption of primary energy, the frost protection strategies mentioned in Point 3.2.1 are
recommended instead of the electrical versions.
P-Band
P-band for the pre-heater PI controller
I-time
I-time for the pre-heater PI controller
Motor-driven valve
Set the control range of the motor-driven valve (0-10 V/2-10 V)
The set value gives the PWW heater return flow temperature at
which the compact ventilation unit will stop and a frost alarm will be
triggered
PWW heater frost protection sets in at the set value plus the
“
Frost protection
”
parameter value
Frost alarm
Frost-P-band
Start-up heating
Initial heating in %. Heating power when switching from
standby to operation.
Stand-by heat
When stopping the ventilation system, the heating
valve will ensure that the return flow from the water
battery does not get below the set value.
Water temperature
Read actual return temperature.
O P E R A T I N G A N D I N S T A L L A T I O N I N S T R U C T I O N S L G
7 5 0 - L G 6 0 0 0
P A G E
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