ELECTRICAL CONNECTIONS
N
1
2
L
N
1
2
N
1
3
2
L
N
1
3
2
N
1
2
L1 L 2 L 3
N
1
2
N
1
2
3
N
1
2
3
L1 L 2 L 3
MOC-MOH
Power supply
mm
2
Ph
Interconnection
(Indoor/Outdoor)
Cooling mm
2
Heating mm
2
Fuse (slow-blow)
A
07 09 12 18
25
35
40 45 55 65
1 1 1
1
3
1 3 1 3
1 1 3 3 3
3x2.5
3x4
5x2.5
5x4
3x2.5
4x2.5
10
32 16
16 10 25 10
35 40 16 20 25
Power supply
220-240V/1Ph/50Hz
208-230V/1Ph/60Hz
MOC 07 - 35 - Cooling only
Indoor unit
Outdoor unit
MOC 25 - 65 - Cooling only
Indoor unit
Outdoor unit
Power supply
380-415V/3Ph/50Hz
460V/3Ph/60Hz
Wire sizes
Terminals N and 1 (see diagrams above) correspond to power
supply to the indoor unit coming from the outdoor
unit.
Compressor power supply is established by terminal 2.
Power supply to the 4-way valve is established by terminal 3.
For further details on wiring of these units, see the diagrams
pasted inside each unit.
MOH 07 - 35 - Heat pump
Indoor unit
Outdoor unit
Outdoor unit
Power supply
220-240V/1Ph/50Hz
208-230V/1Ph/60Hz
MOH 25 - 65 - Heat pump
Indoor unit
Power supply
380-415V/3Ph/50Hz
460V/3Ph/60Hz
START-UP
Before starting the air conditioner, please check the following points:
- That the unit is installed according to instructions given in this
documentation.
- That the unit is correctly wired up.
- That flare connection nuts are tightened.
- That the unit has been evacuated and leak-tested.
- That isolating valves have been fully opened.
- That the refrigerant charge has been topped-up if necessary.
Start the units and check operation in both the cooling and the heating mode.
Unit base plate
Compressor
Diagram n°1
MOC 18 - MOH 18
Coil
DEFROST
Defrost is handled via a defrost management electronic control
board (model with two potential meters and 6 dip
switches, see diagram n°2). This enables defrost cycles to be
initiated when the temperature reaches -5°C at the condenser
coil bend. The end of defrost cycle set point is +10°C. The
duration of the defrost cycle varies depending on operating
conditions but it is limited to a maximum of 10 minutes. Time
delay between successive defrost cycles is 30 minutes.
The defrost cycle can be forced into action by shunting terminals
DEF on the defrost control board in the outdoor unit.
The time delay between successive defrost cycles and the
maximum duration of each cycle are adjustable. If these
need to modified, please contact YORK first for technical advice.
If your unit does not defrost correctly, please check the follow
points carefully:
- Is the refrigerant charge correct ?
- Is the sensor in the right location on the outdoor coil ?
- Low and high pressure switch settings on units :
MOC-MOH 35-45-55 LP = 1.5 Bars HP = 28 Bars
1
Dip Switches for adjusting time delay between defrost
cycles and maximum defrost cycle duration.
2
Female sensor connection
3
Shunt these terminals to stimulate a defrost cycle.
1 2 3 4 5 6
DEF
ON
2
1
3
Diagram n°2 - Adjustable Defrost Control Board
Transformer
