InstallationCâu 29 / 110
When brazing refrigerant copper line sets, dry nitrogen is flowed through the tubing to accomplish what?
a.Add refrigerant charge
b.Prevent oxidation and scale formation inside the tubing
c.Increase joint temperature
d.Test the thermostat
Giải thích
Flowing a small amount of dry nitrogen through the lines during brazing displaces oxygen and prevents the formation of copper oxide scale inside the tubing. That scale can break loose and clog metering devices or contaminate the system. This practice protects the refrigerant circuit.
Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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