[ VII Microprocessor Control ]
(2) Connection to the indoor unit
Use the cables that fit the connectors on the indoor unit control board.
1) External output cable (with a yellow connector)
This cable is used to connect a relay circuit for an interlocked operation with either an electric or a panel heater.Select the
heater output pattern (1st =CN24-1 or 2nd = CN24-2) to use, and connect the cable to the connector on the indoor unit control
board that corresponds to the selection.
2) Panel heater connector (with a green connector)
This connector is used to perform an interlocked operation with a panel heater. Depending on the indoor unit control board
specification, connect the cable to CN22 as appropriate.
CN22 for FAN control
(PAC-YU25HT)
(3) Wiring
A basic connection method is shown below.
Remote control board
Relay circuit
Electric Heater
or panel
heater
Preparations in the field
For relay X, use the specifications given below.
Operation coil
Rated voltage: 12VDC
Power consumption: 0.9W or less
* Use the diode that is recommended by the relay manufacturer at both ends of the relay coil.
The length of the electrical wiring for the PAC-YU25HT is 2 meters (6-1/2 ft.)
To extend this length, use sheathed 2-core cable.
Control cable type: CVV, CVS, CPEV or equivalent.
2
Cable size: 0.5 mm
~ 1.25 mm
Don't extend the cable more than 10 meters (32ft)
Recommended circuit
Wiring diagram
(4) Wiring restrictions
Keep the length of the cable connecting to the circuit board of the indoor unit shorter than 10 meters (32ft).
Longer than 10 meters (32ft) could cause improper operation.
Use a transit relay when extending wiring such as remote wiring.
HWE20150
X
X
2
(16 to 22 AWG)
R
1-phase power
S
supply
208V, 230V/60Hz
R
S
Control board
CN24
Indoor unit
control board
Adapter
CN24
Red
1
White
2
CN22
White
1
2
(applicable only when a panel
heater is connected)
Maximum cable length
is 10 m (32ft)
H1
FS1
FS2
88H
H2
FS1
FS2
88H
26H
88H
- 24 -
Outdoor unit
control board
Please set function
codes that are shown on
outdoor unit service
manuals (DIP S/W
Functions).
FS1, 2 ----- Thermal fuse
H1, H2 ----- Heater
26H --------- Overheat protection
thermostat
88H --------- Electromagnetic contactor
GB