Fujitsu UTY-RVRU - Operation Tips for VRF Systems; Selectable Modes in VRF Systems; Temperature Range and Deadband Guidelines

5-4-2-3 Version
The software version of this controller is displayed on the
right.
6 OPERATION TIPS
6-1 Selectable Modes (for VRF system)
There are restrictions on the selectable modes depending on
the system configuration and operation status.
6-1-1 Heat recovery system
(a) When single indoor unit connected to RB unit
All the modes can be selected.
(b) When a master indoor unit is set in an RB group, only
the mode selected at the master indoor unit (*1) can be
used.(*1:“Fan”cannotbeselectedattheindoorunit
including the master indoor unit.)
(c) When a master indoor unit is not set in the RB Group,
refer to the following table.
Status Selectable Not selectable
Other indoor unit is in cool-
ing operation.
Cool, Dry Custom Auto,
Heat, Fan
Other indoor unit is in dehu-
midifying operation.
Cool, Dry Custom Auto,
Heat, Fan
Other indoor unit is in heat-
ing operation.
Heat Custom Auto,
Cool, Dry, Fan
Other indoor unit is in anti-
freeze operation.
Heat Custom Auto,
Cool, Dry, Fan
6-1-2 When indoor units are connected for cool-
ing only in heat recovery system
(a) Refertothefollowingtable:
Status Selectable Not selectable
At any time
Custom auto,
Cool, Dry, Fan
Heat
6-1-3 RB priority connection in heat recovery sys-
tem
(a) For indoor units or RB groups by RB priority connec-
tion,refertothefollowingtable:
Status Selectable Not selectable
Cooling priority is set by
external input.
Cool, Dry Custom Auto,
Heat, Fan
Heating priority is set by
external input.
Heat Custom Auto,
Cool, Dry, Fan
6-1-4 Heat pump system
(a) Refertothefollowingtable:
Status Selectable Not selectable
Other indoor unit is in cool-
ing operation.
Cool, Dry Custom Auto,
Heat, Fan
Other indoor unit is in dehu-
midifying operation.
Cool, Dry Custom Auto,
Heat, Fan
Other indoor unit is in heat-
ing operation.
Heat Custom Auto,
Cool, Dry, Fan
Other indoor unit is in anti-
freeze operation.
Heat Custom Auto,
Cool, Dry, Fan
(b) When a master indoor unit is set in a refrigerant system,
only the mode selected at the master indoor unit (*2)
canbeused.(*2:“Fan”cannotbeselectedattheindoor
unit including the master indoor unit.)
6-1-5 Outdoor unit priority connection in heat
pump system
(a) Refertothefollowingtable:
Status Selectable Not selectable
Cooling priority is set by
external input.
Cool, Dry Custom Auto,
Heat, Fan
Heating priority is set by
external input.
Heat Custom Auto,
Cool, Dry, Fan
6-2 Settable temperature range
The settable temperature range by operation mode and
indoor unit setting is shown in the table below.
Cool/Dry 64to88°F(18to30°C)
Heat
VRFsystem:48to88°F(10to30°C)
Othersystem:60to88°F(16to30°C)
Custom Auto
Same as the above range, but there are
temperatures that cannot be set due to the
deadband.
6-3 Deadband and set temperature
The Cool and Heat set temperature difference at Custom
Auto cannot be less than the deadband set value. If the Cool
and Heat set temperature difference is the same as the
deadband set value, the Heat setting drops by the amount
of drop of the Cool setting and the Cool setting rises by the
amount of rise of the Heat setting. When the Cool set value
reaches the upper limit, Heat setting exceeding the dead-
band set value cannot be set.
En-28