REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN INSTALLING UNIT
Caution:
The compressor POE oil for R-410A units is extremely susceptible to moisture absorption and could cause compressor failure. Do not leave system open to atmosphere any longer than necessary for installation.
General Information
Systems using R-410A refrigerant run at a pressure of approximately 1.6 times that of similar systems using R-22 and the energy efficiency is comparable. The R-410A refrigerant is a 50:50 mixture of R-32 and R-125.
When installing equipment using R-410A refrigerant, there are a number of standards that must be met:
•Ester oil is used for R-410A.
•It’s important to work with absolute cleanliness.
•Brazing must be done with the use of Nitrogen.
•The system must always be charged in the liquid state.
When refrigerant R-410A is used, the composition will differ depending on whether or not it is a gaseous state. Consequently, always charge the refrigerant while it is in a liquid state.
General Precautions – Refrigerant leaking
The composition of refrigerant R-410A changes when it is gaseous state. Thus, when there is a refrigerant leak the basic performance of the air conditioner may be degraded because of a change in composition of the remaining refrigerant.
Therefore, do not add new refrigerant. Instead, recover the remaining refrigerant with the refrigerant recovery unit. Then, after evacuation, totally recharge the unit with the specified amount of new refrigerant at it’s normal mixed composition state.
Tubing Precautions
The refrigerant R-410A is less is more easily affected by dust or moisture than R-22 refrigerant. Make sure to temporally cover the ends of the tubing with caps or tape prior installation.
Never use tubing which is less than 0.03 inch in thickness (Standard Specification ASTM B-280), since air conditioners with R-410A refrigerant are subject to higher pressures than those using R-22 refrigerant.
