Outdoor temperature-controlled mixed air chamber
For the outdoor temperature-controlled mixed air chamber, two outdoor temperature basic
values are determined with the parameters
Minimum outdoor air rate when the outdoor tem-
perature is smaller and 100 % outdoor when the outdoor temperature is greater which result
in a characteristic curve for controlling the mixed air chamber. The parameter
Minimum out-
door air rate guarantees the required minimum proportion of the outdoor air.
The
summer time operation
(–> section 6.10.3) is always available with this operation mode.
Note:
The proportion of outdoor air can be suppressed during the warm-up phase with Fb43 = ON.
Functions
WE
Configuration
Sensor F7, mixed air or extract air temperature
Fb7 = OFF,
option:
AT
Operating action Y2
OFF
Fb22
Circulating air mode after system start-up
OFF
Fb43 (not with supply air control)
Parameters
WE
Range of values
Min. outdoor air rate when the outdoor
temperature is smaller
0 °C
–10 to 50 °C
100 % outdoor air when the outdoor temp. is greater 18 °C
–10 to 50 °C
Minimum outdoor air rate
20 %
0 to 100 %
5.4.3 Heat recovery unit (HRU)
The heat recovery unit is controlled from the control output Y2. It is implemented by a PID
control algorithm with the parameters
K
P
HRU, T
N
HRU and T
V
HRU.
48
EB 5477 EN
Control methods and system components
Fig. 17 · Outdoor temperature-controlled mixed air chamber
Control signal
Y2 %
Outdoor temperature