Float valve

Float valve, either high or low side, can serve as the measuring device. On the high side float, located in the liquid line, allowing fluid in the bottom side, when a sufficient quantity of refrigerant has been compressed to move float. No liquid remains in the receiver. Refrigerant charge enough to fill the coils will be put into the installation system. This type float, the previously widely used, currently restricts the use of some types of industrial and commercial systems.

On the low side of the float valve maintains a constant level of liquid in the evaporator. It is used in flooded evaporators type, where the average cooling flows through the pipes in the bathroom refrigerant. On the low side of the float is more critical than operations on the high side float and should be made more precise. Failure will lead to the evaporator to fill during shutdown. This condition can lead to serious knock and possible problems at compressor start-up.

Needle valves, either aperture or Packed type, can be used as expansion valves. As such, they are usually installed in a bypass route around automatic or thermostatic expansion valve. They are placed in operation during normal management has failed or has been removed for repairs.