• VRV ® Systems • Installation procedure 17• Installation procedure1 Installation of outdoor1 - 7 Field wiring1 - 7 - 4 Examples[Setting the cool/heat operation type]1 Performing cool/heat setting with the remote controller connected to the indoor unit.Keep the COOL/HEAT selector switch (DS1) on the outside unit PC board (A1P) at the factory setting position OFF. Remote controller2 Performing cool/heat setting with the COOL/HEAT selector.Connect the COOL/HEAT selector (optional) to the A/B/C terminals and set the COOL/HEAT selector switch (DS1) on the outside unit PC board(A1P) to ON. COOL/HEAT selector• For the above wiring, always use sheathed vinyl cords with 0.75 to 1.25 mm2 or cables (2 core wires). (3 core wire are allowable for the COOL/HEAT selector only.)• All transmission wire is field supply.• If the following limits should be exceeded, be careful that any abnormal transmission may be caused;Maximum wiring length ................................1000 m or lessTotal wiring length .......................................2000 m or lessMaximum branching ....................................16 branching or lessWire length between outside unit ................30 m or less• Never connect power supply to any connection wiring and its terminal block, otherwise the entire system may be damaged.• Up to 16 branches are possible for transmission wiring. However no branch is allowed after branch. Branch Branch after branch• The wiring to the indoor units must be connected to the F1/F2 (To IN/D UNIT) terminals on the PC board in the outside unit.To indoor unit OnOffOutOnOffOut