Fujitsu AUU7RLF Design & Technical Manual page 170

[Installation precautions]
When inside the When the indoor unit is installed where the inside of the ceiling
ceiling is high is 30°C (86°F) RH80% or greater, the dew point temperature
temperature and of the outer perimeter may become higher than the cabinet
high humidity surface temperature and moisture will condense on the surface
of the cabinet and water drops may fall inside the room.
→Refer to Fig.A
In addition, the humidity may vary considerably the same as
when the inside of the ceiling is close to hermetically sealed
and used as the outside air intake path.
Moist air curve
Relative humidity 80%
Dry bulb temperature 30°C (86°F)
Fig.A
When using an When using an external duct to take in new fresh air, etc.,
external duct condensation may form on the surface of the duct due to the
effect of the outside air temperature and the humidity inside
the ceiling.
When the If the cold or warm air blown out from the air conditioner
remote controller directly contacts the thermostat section of the remote
installation site is controller, the outlet temperature of the air conditioner may be
bad sensed and room temperature control will be different from the
room temperature and "not cooled" or "not heated" or other
trouble may occur.
In addition, there is the possbility that the same kind of trouble
may also occur when the remote controller is effected by direct
sunlight.
Contents
Work method when reinforcing the heat insulation
of on-site piping
Condition which Slit of heat insulating
requires addition
material facing
of outside heat
upward
insulation
Covered gas
pipe (heat
insulation
strengthened)
Heat insulating
material (procured at
the site)
Contents
- (01 - 166) -
Countermeasures (Reference)
(1) Add heat insulating material to
the outside of the indoor unit
cabinet.
*Regarding the cassette type,
use of the "high humidity
correspondence kit (option)" is
recommended ..
(2) Strengthen the heat insulating
material of the refrigerant
piping and drain piping also
→Refer to Fig.B
(3) When the humidity inside the
ceiling changes considerably,
install a ventilation port.
Heat insulation
reinforcement material
Flare connection
(procured at the site)
Small exposed part
Binding material
of copper pipe is
desirable.
Fig.B
Countermeasures (Reference)
(1) Always perform heat insulation
processing.
(Heat insulating material:
Glass wool 25mm (1 in.) thick
or more.)
(1) Install the remote controller
where it will not be directly
exposed to the cold or hot air.
(2) Install the remote controller
where it will not be directly
exposed to sunlight or strong
lighting.
To indoor unit
Fit tightly
(purpose is to
cover the sealant)