Extra copper line at Evaporator. See photo.

[Gene South]

Extra copper line at Evaporator. Maybe I am overtired but don't recall seeing of these before. What is extra copper line ?

[Zibby Bujno]

looks like a test port brazed in suction line by installer. Waste of part/money.

[bruce m graham III]

ditto on service port and waste of $$$ pressures should be checked at the condenser

[Jim Luttrall]

Factory installed port. Lots of units have them.

[Bob Cone]

It is likely an external equalizer port connection for use with a thermostatic expansion valve.

[Phillip Stojanik]

Extra copper line at Evaporator. Maybe I am overtired but don't recall seeing of these before. What is extra copper line ?

Its factory installed and is used to enter, and subsequently relieve, the shipping pressure in the coil (usually just dry nitrogen).

Contractors use this to quickly verify that the boxed coil they are buying has held its shipping pressure upon pickup at the loading dock. If there is low or no pressure left in the coil then he will not accept it.

After installation it serves no particular purpose.