8. Installation
13
MULTI/SINGLE CAC
Indoor unit
Ceiling Mounted cassette 1-way
8.2 Precautions regarding cassette indoor unit installation
Main points about the indoor installation
• In general commercial places and offices though the height of the ceiling is 2.7 m, the ceiling height could be
over 3 m.
• In such cases because of the temperature difference with the floor the heating effect can fall down.
• Countermeasure method
1. Air conditioner should be able to operate in high ceiling operation mode.
2. Plan to install the circulator.
3. The air discharge port should be made to give more airflow to the down floor directions.
4. The gate or exit of the building is protected by dual door system to minimize inflow of outdoor air.
In case the floor or surfaces is contact with the outdoor air directly
• If the floor of air conditioned room contact with the outside air, like the store room or garage, the floor
temperature will be decreased and users can have a cold feeling in the feet.
• In such places where the feet comes in direct contact with floors will give a cold feeling to the foot.
CAUTION
– In case there is a cold air intake,
» The duct surface may have some dew drops. So a insulation on the duct is a must.(Insulation material: a
glass wool of thickness 25 mm will be appropriate.)
• Countermeasure method
1. Use the carpet on the floor.
(compared to the tiles the carpet over it will have a 3 degree rise in temperature)
2. Insulating the floor.
3. Floor heating.
In case of high temperature or humidity between the false ceiling and ceiling slab
• In case of places having the temperature and humidity of the
surrounding water sources(sea, river etc.)
• In case the steam is generated between the false ceiling and
the ceiling slab due to some nearby by steam source.
• In case of temperature of 30 degree and humidity above
80%, the units body as well as the piping insulation should
be strengthened. Refer to the psychrometric chart.
Discharge
Suction
Hot air
High elevation
of the ceiling
Outdoor
side
(Entering of air by
frequent opening
and closing of door)
Cold air
Indoor
Outdoor side
Outdoor side
Outdoor side
Low temperature
of the floor
(50~100mm
Insulation required)
Garage
30˚C
Psychrometric chart
Enhance additional
insulation required area
Relative humidity
