I'd probably crosspost a request to alt.hvac; those guys are very helpful
when someone who isn't a trained hvac technician asks a question. *Be sure
and tell them you are a homowner, and that you have a done a few DIY
projects (like a fence and a water faucet) in the past so they know you
would be capable of the work. *

Jon

Jon you are a mean person, hvac guys hate anyone to touch an a/c
without a licence, especially a homeowner. They really wish this to
become a death penalty crime. This group will chew him up if he does
this, a bunch of arrogant (*&^%$) people there.

Scott