Mitsubishi Electric TC-24B Instruction Book page 30

Usage - Main Menu settings - System Management
Using the System-Changeover function
2
Use the System-Changeover mode to automatically change a group of indoor units that are connected
to the same outdoor unit over between the Cooling and Heating modes according to temperature
changes.
Use this function to control the indoor units that do not have an automatic changeover mode. They can
be operated in the Heating mode in the morning, and then automatically changed over to the Cooling or
Heating mode all at once in the afternoon, for example, without the need to manually change the mode
via each remote controller.
* This function should not be used in conjunction with the System-Changeover function on the outdoor
unit or other system controllers.
* When the System-Changeover mode is set to "Auto", the operation mode is selected based on the
demands of the majority of the group, taking into consideration the capacity of each indoor unit.
When it is set to "Representative Group", the operation mode is selected based on the demand of the
representative group through updating its status every 15 minutes and changing over to the cooling or
heating mode as necessary.
Because the operation mode is selected based on the demands of the representative group or of the
majority of the groups, not all areas may be air conditioned to the optimum temperature.
• If the temperature limits are set too high or low (see P46), the System-Changeover function may
not work properly and the units may not operate in the expected mode (Cooling or Heating).
• The System-Changeover function is not available for the following types of products:
Simultaneous Cooling/Heating units (with Auto mode), Mr. SLIM®, LOSSNAY, DIDO controller, and
Air To Water (PWFY).
Main Menu > System Management
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Main Menu > System Management > System-Changeover
Block No.
Displays the block number. All units
in each group are operated in the
same operation mode. The TC-24B
automatically creates blocks based
on the refrigerant pipe connection
information and the group setting
information on each unit.
Group list
Displays the number assigned to the indoor unit groups that are connected to the
outdoor units in a specific block. Select a representative group from this list when
the "Representative Group" is selected for the System-Changeover mode.
1. Touch the [System-Changeover] button on the [System Management] screen.
2
2. Touch the Change mode button to select between "None", "Averaging", and "Representative Group".
1
System-Changeover
mode
None (default) Select this option so as not to use the System-Changeover function.
The operation modes (cooling/heating) will be changed-over based on the following:
Temperature differences between the preset temperature and the room temperature of all
indoor unit groups that are connected to a specific outdoor unit, AND the capacity of each
Averaging
indoor unit in each group.
* The operation mode of the groups of units that are not operating, or the ones that are
1
The operation modes (Cooling/Heating) will be changed-over based on the temperature
difference between the preset temperature of the representative group and the room
2
Representative temperature.
Group
* When the air conditioning units in the Representative Group are not operating, or they are
When "Representative Group" is selected, the group that is currently
designated as the Representative Group will be displayed.
* To designate a different group as the Representative Group, select
a new group on the screen that appears (shown right) when the
[Representative Group] button is pressed, and then touch the
2
[OK] button.
• The initial setting for the Representative Group is the group in a
specific block with the smallest group number.
• In a group where both Air To Water (PWFY) and Air conditioning
units are connected to Y series outdoor unit, System-
Changeover function may not function properly.
3. Touch the [Save] button.
3
Usage - Main Menu settings - System Management
3
Setting
operating in the Fan or Auto mode, will remain the same.
operating in the Fan or Auto mode, the System-Changeover function will work in the same
way as when the System-Changeover mode is set to Averaging.
Operation mode
Displays the current operation
mode.
Cooling:
Heating:
1
2
Display Block Information button
Displays the addresses of the
outdoor units and the names of the
groups in a specific block.
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