Night purge
The night purge provides night purging to cool down the building with cool outside air during morning hours before occupation time.
This function needs a room temperature sensor.
Note: To disable the function of night purge, set parameter NIPU-01 to a value of “0”
The function night purge is active if all the following conditions are true;
The On/Off delays for the night cooling mode are defined by the settings NIPU-06/ NIPU-07.
During occupancy, the functionality of the night cooling mode is automatically off.
During night cooling mode, the plant mode is set to the value "night purge" ("3").
The night purge function will automatically be overridden by the occupied period, if the input "Occ_Period" becomes true.
Description |
Default value |
NIPU-01: time before occupied period |
6 h |
NIPU-02: outside air temperature low limit |
12 °C |
NIPU-03: room temperature shift; "0" -> room temp. = room temp. setpoint |
2 K |
NIPU-04: difference between RMT and OAT |
4 K |
NIPU-05: switching differential for NIPU-02, NIPU-03, NIPU-04 |
2 K |
NIPU-06: switch on delay |
300 sec |
NIPU-07: switch off delay |
300 sec |
Input "NIPUEnable"
In some use cases it is useful to block night purge. For example in a school after lunch time a classroom is unoccupied for some hours, night purge starts to cool down the room. If now the room is occupied again late in the afternoon it needs to be heated up again.
To avert this waste of energy, set the input "NIPUEnable" to "0" combined with a schedule or a logic.