Describe signs of moisture in the refrigeration system. How to remove the moisture from the system?
Moisture often comes into refrigeration system as an atmospheric humidity during maintenance. That is why very important to vacuum the system (or blow by N2) after maintenance or repairs finished in order to remove air and any possible moisture.
Moisture gets frozen in the Thermo Expansion Valve with the formation of internal ice cork. This could be judged by pouring the hot water on the valve: the cork melts and you can hear the hissing sound of Freon passing through the TXV.
Thermo Expansion Valve ceases to perform its functions because of ice cork which fixes it in some position.
If it stuck in minimal flow position the Evaporator lacks Freon and cooling capacity reduces. At the same time, compressor discharge pressure rises and may auto cut-off it.
If TXV stuck in maximum flow position the liquid Freon may get to the outlet of the Evaporator. This can be seen by the frost on the Evaporator outlet pipe. Liquid Freon may get into the compressor suction and damage it.
Refrigeration systems equipped with the Dryers which specially dedicated for moisture entrapment. Pay attention to replace Dryer elements as per Maker's instructions. If your system got moisture replace Dryer with a new one, probably the old already exhausted. Keep monitoring the TXV and Evaporator frost and defrosting it as required. The moisture will travel the system than and will be absorbed by the dryer finally.
