7-2. Check Items before Test Operation (before powering-on)
Prior to the test operation, check the following items to verify there are no problems with the installation work.
Main check items for electric wiring
The communication system differs from that of R22 or R407 refrigerant “Modular Multi
System
” air conditioners.
Check wiring points again carefully.
(1) In the case that a central control system is not connected:
NOTE
The figure above does not show all the electric wires.
For details, refer to the installation manuals for the outdoor unit, indoor unit, remote controller, or optional devices.
k
c
e
h
C
s
m
e
t
i
k
c
e
h
c
n
i
a
M
(1) Are the indoor and outdoor communication lines of the
outdoor
unit connected to the U1/U2 terminals?
(2)Is the relay connector between the U1/U2 terminal and the U3/U4 terminal
disconnect
? (Set up at
shipment from the factory)
(
3
)Is the
terminator resistor
(SW30-bit 2) on the interface PC board of the
outdoor
unit turned on? (Set
up at shipment from the factory)
(
4
) Is the end terminal of the shield wire open?
(
5
) Is the end terminal of the shield wire earthed at the
outdoor
unit side?
U1
U2
U1
U2
U1
U2
U1
U2
U1
U2
U3
U4
B
A
A B
A B
B
A
(1)
(2)
(
3
)
(
4
)
(
5
)
Outdoor unit
Indoor unit
Remote
controller
Remote
controller
Remote
controller
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