UAB AMALVA we reserve the right to make changes without prior notice
38
EN
V2-C5-15-03-v1
6.6. Settings of unit modes
6.6.1. Operation modes
Six operation modes of the unit are possible:
1. There is two
Comfort
and two
Economy
modes, for each of them the user can set air flow and temperature;
2.
Program
– in this mode the unit operates according to the preset schedule;
3. The
Special
mode allows the user not only to set air flow and temperature, but also to select blocking or using
cooling, recirculation and humidification functions.
6.6.2. Flow control modes
The following supply and extract air flow control modes are designed:
•
CAV
– constant air volume control mode. The unit will supply and extract a constant air flow which is preset by
the user, irrespective of any changes occurring in the ventilation system;
•
VAV
– variable air volume control mode. The unit will supply and extract an air flow with regard to the ventila
-
tion needs in different rooms. In case of frequently changing ventilation demands this air volumes mainte-
nance mode signally reduces unit exploitation costs.
It is possible to use a simplified VAV control function, “single-flow VAV control”. It means that the performance of
this function requires only a single air flow pressure sensor, which is installed in a variable air duct system (e. g. in
supply air). This variable system is called the master ventilation system, according to which control is performed,
while the other air flow (in this case, discharged air) operates as the slave ventilation system and always follows
the master one. If the supply air requirement in the ventilation system which is assigned as the master system
decreases, the intensity of discharged air in the slave system is reduced correspondingly by the same percentage.
If the variable air volume control function is mode is selected, the initial
calibration of the control mode must be performed (see Paragraph 6.9.6);
otherwise, the unit will not operate if the VAV mode is selected.
•
DCV
– direct controlled volume. The air handling unit will operate similarly as in the CAV mode, but air volumes
will be maintained directly in accordance with the values of the B6 and B7 analog input signals of controller.
After giving the signal 0... 10 V to the appropriate input, it will be converted according to the current determined
air volume. For example, if the maximum air flow of the unit is 1000 m
3
/h, setpoint in the panel – 800 m
3
/h, and
the B6 input value – 7 V, the unit will supply constant air volume of 560 m
3
/h, i. e., 70 % of the set value. The
same applies to the exhaust air only by B7 input (see picture 5.3 b).
