6  Building air conditioning controls
CSNET Manager LT/XT
TCGB0106 rev.0 - 12/2014
561561
6
Auto cool/heat
The outdoor units of 2-tube systems and are not designed to operate in the automatic Cool/Heat mode when more than 
one indoor unit is connected to the same outdoor unit, but only in the cool or heat mode. Thus all indoor units connected 
to the same outdoor unit should be changed from one mode to another at the same time. The same is applicable to the 
3-tube outdoor unit systems, for all indoor units connected to the same CH Box.
However, operation in the automatic Cool/Heat mode is available through CSNET Manager.
In temperate seasons, CSNET Manager calculates the main need of the indoor units for each of the outdoor units in the 
systems mentioned above, selects the mode needed for most of the units in the system and adjusts the remote controller 
accordingly.
With the aim of giving the system time to be established in a particular mode, its requirements are checked for at least 20 
minutes after the last change carried out. This process is continuous for as long as the indoor units are set to Auto.
If the systems are correctly designed, i.e. if all the indoor units of the same outdoor 2-tube unit have similar cooling and 
heating demands, then it is possible to completely automate heating in the morning (for example), cooling in the afternoon 
and heating once more at night.
Users maintain local control over the temperature in the room by the remote control.
There are two ways in which CSNET can decide whether the operation mode should be established in AUTO.