Swegon 20210201, Technical Manual

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Water – Air with temperature control
Flow %
100%
50%
20%
No
occupancy
Occupancy
CO
2
Air 1
Temperature
Water
Air 2
Temperature/CO
2
26 ° C
1000 PPM
24 ° C
800 PPM
22 ° C
600 PPM
Time period
Figure 8. Typical diagram dealing with the water-to-air sequence with temperature control.
Note! Air 2 is valid only for W4.2
The sequence involves the following: If occupancy is registered in the room
and if the temperature is at a certain level, the system starts a cooling
process that cools down the room by circulating chilled water in the water
pipes.
If the temperature rises more and the chilled water is not sufficient for
maintaining the required temperature, the cooling process is supplemented
by increasing the airflow.
If the level of carbon dioxide in the room exceeds a certain level, the airflow
is increased in order to reduce the level and keep it constant.
Operating Mode
Depending on the status of connected sensors, the controller adjusts the
outputs from any of several possible operating conditions.
The various operating conditions described here are based on occupancy
in the room and the status of the window contact, condensation sensor,
carbon dioxide sensor and the current pressure.
Occupancy Window Condensation
Carbon
dioxide
Airflow Cooling
No No No No Low ECON
Yes No No No Normal Normal
Yes Yes No No Low Closed
Yes No Yes No High Closed
Yes No No Yes High Normal
Yes No No No Normal Normal
CONDUCTOR W4
14
Swegon reserves the right to make design changes.. 20210201