Plant mode
During normal operation, the air handling unit control strategy will control the cooling coil.
The input "PlantMode" from the control strategy module is decoded to provide the required cooling valve output signal. The table below shows the cooling coil overrides depending on the plant mode.
Fire overrides have the highest priority over plant mode overrides.
Plant mode |
Cooling valve |
0 = off |
closed |
1 = optimum start |
auto |
2 = night cycle |
auto |
3 = night purge |
closed |
4 = occupied period |
auto |
5 = extended operation |
- |
6 = delayed switch off |
auto |
11 = duty cycling |
closed |
20 = frost protection |
closed |
21 = fan failure |
closed |
30 = fire override |
closed |