HVAC home A/C question

[bad Chad]

I have a house with a year old A/C unit.  I was looking it over and noticed that the refrigerant line coming into/out of the condenser unit is insulated as it should be.  However once it passes into the co housing it has no insulation on the lines, should it?  Should I pop the top and put some pipe insulation on the copper tubes?

[Perazzimx14]

The insulation is to keep the condenser (liquid) line sweating in finished areas and also keep the coldest liquid going to the evaporator coil. The evaporator (hot gas) line is left uninsulated to help flash off heat before entering the compressor to start the cycle anew. 

What you have is normal and nothing would be gained from insulation.

[bad Chad]

Thanks brother.  I don’t know my way around a/c very much, but I was sure one of us could set me straight!

[Rick in WNY]

That's one of the nice things about this place, the "hive mind" here is made up from a bunch of people will all kinds of expertise.

Ask the questions, someone here is bound to know the answer. 

[Wayne Orwig]

The insulation is to keep the condenser (liquid) line sweating in finished areas and also keep the coldest liquid going to the evaporator coil. The evaporator (hot gas) line is left uninsulated to help flash off heat before entering the compressor to start the cycle anew. 

What you have is normal and nothing would be gained from insulation.

I think you have the lines reversed. The liquid line to the evaporator gets hot. The returning vapor line is cold.

Keeping the vapor line cold, keeps the pressure at the compressor a bit lower. I'm not sure there is anything to be gained by insulating that short bit of pipe, in a way that would hold up to the heat, rain, wind and vibration.

[Perazzimx14]

I think you have the lines reversed. The liquid line to the evaporator gets hot. The returning vapor line is cold.

Keeping the vapor line cold, keeps the pressure at the compressor a bit lower. I'm not sure there is anything to be gained by insulating that short bit of pipe, in a way that would hold up to the heat, rain, wind and vibration.

Quite possible I had lines reversed. That was after about 8 Yuengling and a double vodka rocks

[Markcarovilli]

well one is hot and one is cold - the one with the insulation is the cold one.........

Mark

[elvisboy77]

Both the Yuengling and the Vodka on the rocks w/ a squeeze of lime were cold

Lol

[oldbike54]

 The larger line is known in the parlance as the *suction* line , speaking of which ... several year back I was sweating in the refrigerant lines on a new condensing unit (the big ugly thing outside) . When I touched the suction line to wrap a cooling rag around it there was a serious jolt of electricity that made me tingle . Now , I ain't all that smart , but even I knew that wasn't right . Out comes the Fluke , sure enough , there is 100 V at about 2 amps present in the line . WTH ? The homeowner was the GC on the house , and was a slightly off center pilot for the Okie state troopers , He was running the job from long extension cords , and one was chafed along a 6 inch section . So right when I wrapped the rag around the suction line , one of the carpenters was pulling on an extension cord . Yep , you guessed it , the chafed section was laying on the copper refrigerant lines running in the attic  literally 

 Dusty