21
MMU-AP___4HPUL
TCTC-E20-VRF010
MMC-AP___8HP-E
TCTC-E14-VRF001-2
3. Fresh Air Intake
Usage
Fresh air is taken by using Fresh-air chamber and Fresh-air inlet box. And also is subsidiarily taken by using
Auxiliary fresh air flange through the knock-out hole of the indoor unit body.
Caution
1. Be sure to provide air return.
2. The fresh air shall be treated by heat reclaim ventilator or the like.
3. Recommended treated air temperature is 54 °F to 86 °F.
4. Be sure to decide the fresh air volume so that mixed suction air with fresh air keep operating temperature.
Provide an air filter in fresh air way to prevent sucking dust.
5. Be sure to insulate the fresh air duct.
In order to accelerate starting up in heating mode, implement pre-heating operation by cutting off Fresh Air
Intake.
6. The operating sound might increase when fresh air intake.
Characteristics between air volume of branching duct and static pressure
Following fresh air intake ratio is available by using the booster fan.
1. Fresh-air inlet box with Fresh-air chamber
Up to 88 cfm and 10% of rated air volume
2. Auxiliary fresh air flange through the knock-out hole of the indoor unit body
Up to 24 cfm
Inter - lock circuit
1. Connect the driving relay of the duct fan (DC 12 V) between 1 and 6 on the indoor P.C.board.
Part indicated with a bold line is the connecting circuit.
After installation, implement a test run to check that the duct fan of the indoor unit start / stop simultaneously.
(Implement the test run following to the installation manual of the indoor unit.)
0
Fresh Air Volume (cfm (m³/h))
Static Pressure (in WG (Pa))
Fresh Air
Chamber
Static Pressure = P (atmospheric) - P1
P1
Booster fan
(Atmospheric)
P
1.18 (295)
0.98 (245)
0.78 (195)
0.58 (145)
0.38 (95)
0.18 (45)
-0.02 (-5)
118
(200)
88.3
(150)
58.9
(100)
29.4
(50)
Using of Fresh-air inlet box
Using of Auxiliary fresh air flange
Duct fan motor
Power supply of
Duct fan motor
R
FAN
1
2
3
4
5
6
1
2
3
4
5
6
R
Relay for
duct fan
Closed end
terminal
Closed end
terminal
Indoor
P.C.board
CN60
(White)
+12 V
GND