Hitachi RPI-0.8FSG1 Service Manual page 369

[Example]
* In Case of Start-Up in Simultaneous COOL/HEAT Operation Mode
* In Case of Start-Up in Cooling Operation Mode (and Changeover to Simultaneous COOL/HEAT
Operation Mode Afterward)
<Attention for Automatic COOL/HEAT Operation>
In the case that the indoor units are operated under an automatic cooling/heating operation by pressing the
AUTO COOL/HEAT switch, pay attention to the followings.
(1) Interference of Cooling Unit and Heating Unit
[Phenomenon]
In the case that more than 2 indoor units are closely installed and operated in the same room, each
indoor unit interferes with the next unit, resulting in inefficient operation.
[Countermeasure]
Do not use CH units individually for each indoor units in a same room.
In such a case, connect the indoor units in a same room to one CH unit and operate indoor units in the
same operation mode, if it is possible.
Outdoor
Unit
(2) Fan Operation When Changing Cooling/Heating Operation Mode
[Phenomenon]
In the case that room temperature rapidly increases during this automatic COOL/HEAT operation, the
operation mode is changed in order, heating operation => fan operation => cooling operation.
During this mode change, the fan operation continues for more than 10 minutes in order to avoid
unwanted influences to other indoor units.
[Countermeasure]
It is recommended that other systems be considered if very precise temperature control is required.
ON
ON
10 to 20min.
Cooling
CH Unit
FIELD WORK INSTRUCTION
Cooling
Heating
Cooling
Heating
Heating
CH Unit
Outdoor
Unit
5-9