The FTV series thermostatic valves are systems that are controlled by a thermostat and direct the oil from the oil tank to the temperature.
When the oil reaches a certain temperature, it prevents the oil from going directly to the screw and allows it to circulate through the radiator. The oil temperature in the radiator is lowered to a certain degree and then comes back to the thermostatic valve and is sent to the screw.
This system keeps the temperature of the compressors at certain levels during operation and prevents them from overheating.
In cold weather, it does not send the oil directly to the radiator and allows it to warm up to a certain degree