Growth of liquid lines
If the liquid refrigerant should rise from the condenser or receiver expansion valve at the higher level, there will be a loss of hydrostatic pressure of the refrigerant may reach its peak and starts flashing. In such circumstances, the bubbles will show in the sight glass and disappear, adding more refrigerant in the system.
Where high-rise not avoid, supercooled liquids should be enough to keep fluid in the bottom of pressure. Hypothermia can be accomplished by setting hypothermia condenser coil with water cooling and cold coil, suction liquid heat exchanger in front of the Elevator, or refrigerated subcooler.
To reduce the risk from these troubles, the condenser should be always higher than in the evaporator, if this can be arranged. The same effect will occur where the liquid line takes the heat on the horizontal run, where it may be in the same duct, as hot tubs, or go through a boiler room. If the liquid in the sight glass is blinking, even with the addition of refrigerant, the possibility of such additional heating should be investigated. To cure this, pipe insulation.