A four port reversing valve for a reversible-cycle refrigeration system having a compressor is constructed with the reversing valve having a first inlet port adapted to be connected to the compressor and second, third, and fourth ports. The four port reversing valve is further provided with a valve member operable between first and second positions. The valve member in its first position connects the first inlet port with the second port and the third port with the fourth port, and the valve member in its second position connects the first inlet port with the fourth port, and the second port with the third ports. The second and third ports and the third and fourth ports are arranged so that the angle between the ports is about 135°. In one embodiment the valve member rotates, and in another it translates linearly. Several means are disclosed for actuating the valve member.