The second reversing four way valve is mounted in the refrigerant circuit either to connect selectively {HEAD ~ the outlet} of {TAIL ~ one coil} used as a condenser to the expansion means associated with the other or evaporator coil or to connect some circuits arranged in a parallel in the coil used as an evaporator to a suction line of the compressor 
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The second reversing four way valve is mounted in the refrigerant circuit either to connect selectively { HEAD ~ the outlet } of { TAIL ~ one coil } used as a condenser to the expansion means associated with the other or evaporator coil or to connect some circuits arranged in a parallel in the coil used as an evaporator to a suction line of the compressor
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH