What is it and what is its function?

[David A. Andersen]

You all can change the rusted POS or pay several hundred dollars when it leaks and sucks in all kinds of air and moisture. If your lucky the compressor will not fail or coke from heat and moisture in the oil...

How old is that thing anyway?
Maybe it's on the list of things to replace before their time!

[Joe Funderburk, CMI]

Originally Posted by dandersen

You all can change the rusted POS or pay several hundred dollars when it leaks and sucks in all kinds of air and moisture. If your lucky the compressor will not fail or coke from heat and moisture in the oil...

How old is that thing anyway?
Maybe it's on the list of things to replace before their time!

David, do you call out the absence of a filter/dryer as a defect? If so, would you mind sharing that language?

[David A. Andersen]

No!
A filter dryer is a "good idea" when installing an new split HVAC system.

When there is a refrigerant circuit problem ( failed compressor) a dryer should be installed/changed in every case.

When you see those dark spots on the outside of the filter/dryer, that means there is deep corrosion and the device should be replaced.

[pnarron]

I like the button, and thanks for everones help.

[sparksnmore]

Wouldn't hurt to recommend replacing it while the refrigerant can still be reclaimed but hey, I wish all HI's would say dryers with rust on them should be replaced, we could keep busy replacing them all.
However, filter-dryers are made of fairly heavy metal and CAN last for years looking rusty before they actually rust through.