A second four way reversing valve is provided in the refrigerant circuit between outlets of indoor and outdoor coils to direct refrigerant through {HEAD ~ liquid lines} of the refrigerant circuit from {TAIL ~ the outlet} of one coil used as a condenser to the expansion means of the other coil used as an evaporator 
A second four way reversing valve is provided in the refrigerant circuit between outlets of indoor and outdoor coils to direct refrigerant through { HEAD ~ liquid lines } of the refrigerant circuit from { TAIL ~ the outlet } of one coil used as a condenser to the expansion means of the other coil used as an evaporator
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH 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