Check Items Before Test Operation (Before Poweringon) - Carrier MMY-MAP0724FT9UL Service Manual

8-2. Check Items before Test Operation (before poweringon)

Prior to the test operation, check the following items to verify there are no problems with the installation work.
(1) In the case that a central control system is not connected:
(1)Are the indoor and outdoor communication lines of the header unit connected to the U1/U2 terminals?
(2) Is the relay connector between the U1/U2 terminal and the U3/U4 terminal removed?
(Set up at shipment from the factory)
(3) Is the communication line between outdoor units connected to the U5/U6 terminal?
(4) Is the terminal resistance (SW30-bit 2) on the interface PC board of the header unit turned on?
(Set up at shipment from the factory)
(5) Is the end terminal of the shield wire open?
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.
(1)
Header unit (A)
U3
Outdoor unit
U1 U2
(6)
U1 U2
Indoor unit
A B
Remote
controller
Main check items
(2) (4)
Follower unit (B)
U4 U3 U4
U5 U6 U1 U2 U5
U1 U2 U1 U2
A B A B
Remote Remote
controller controller
– 80 –
(3)
U6
(5)
U1 U2
A B
Check