Fujitsu AIRSTAGE J-IIIL Design & Technical Manual page 779

¢ Economizer input function
Cooling economizer consists of ducts, dumpers, and automatic controling system. In cold or warm
climate, the economizer reduces or stops the VRF comperssor, providing cooling using outside air.
• Example of economizer
Room space
• How to use economizer
Operation
mode
Heating
Fresh air
intake cooling 34 to 55°F (1 to 13°C)
Combined
55 to 75°F (13 to 24°C)
VRF cooling
75°F (24°C) or more
*: Minimum fresh air requirements are specified in ASHRAE Standard 62.1.
3-2. External input
Return air damper
Environmental Intaking
condition fresh air
Cold climate
Minimum*
34°F (1°C) or less
Cool climate
Optimum
Warm climate
Hot climate
Minimum*
Exhaust damper
Air
conditioner
Heating
Stop
100% Cooling
Cooling
- (08-25) -
Economizer
logic module
Fresh air damper
Economizer Remarks
Heating by air
Disabled
conditioner
Cooling by intaken
Enabled
fresh air only
Combined cooling
Enabled by intaken fresh air
and air conditioner
Cooling by the air
Disabled
conditioner
3. Indoor unit