7 English6. REFRIGERANT PIPING WORK• For instruction for installing piping between the outside unit and BS unit, selecting a refrigerant branch kit,and installing piping between the refrigerant branch kit and the indoor unit, refer to the installation manualand equipment design materials included with the outside unit.• Before beginning the work, always check to make sure the type of refrigerant used is R410A. (The unit willnot operate correctly with a different type of refrigerant.)• Insulate all of the piping including the liquid pipes, HP/LP gas pipes, suction gas pipes, gas pipes, equalizerpipes (piping between outside units when an outside multi-unit system), and the pipe connections for these.Not insulting these pipes could result in water leaks or burns. In particular, suction gas flows in the HP/LPgas piping during full cooling operation, so the same amount of insulation as used for the suction gas pipingis required. In addition, high-pressure gas flows in the HP/LP gas piping and gas piping, so use insulationthat can withstand more than 250°F.• Reinforce the insulation material when necessary for the installation environment. Refer to the following asa guideline.• For 86°F, RH75% to 80%: Thickness at least 5/8 in.• For 86°F, over RH80%: Thickness at least 13/16 in.If not reinforced, condensation could form on the surface of the insulation. For details, refer to the Engineer-ing data book.NOTES• This product only uses the new refrigerant (R410A). Be sure to use the special pipe cutters for R410A, dur-ing installation.• Make sure that nothing besides the specified refrigerant, such as air, gets into the refrigerant piping.• If refrigerant gas leaks during the work, ventilate the area. (The outside units are filled with refrigerant.)6-1 PIPING MATERIAL SELECTION• Use only pipes which are clean inside and outside and which do not accumulate harmful sulfur, oxidants,dirt, cutting oils, moisture, or other contamination. (Foreign materials inside pipes including oils for fabrica-tion must be 9 mg/10 ft or less.)EL. COMPO. BOX lidCoil coverTop PanelEL. COMPO. BOX5)-2(Move theEL. COMPO. BOX)1)1)2)4), 6)3), 7)3), 7)3), 7)3), 7)(Rotate 180 degrees)6)7)(Rotate 180 degrees)2)9)9)8)8)4)2)[Before change 5)-1][After change 5)-3]EL. COMPO. BOXEL. COMPO. BOXRemove the wire from thewire clip.Pass the wire through thewire clip.Fig. 4