Thank you, gentlemen;
From this discussion, I now have a much greater appreciation for my venerable Pace unsoldering system. You have provided some additional thoughts for maintenance procedures. The fellow I bought it from could not locate the manual for it, so I have just been going from my observations and what I had learned when at the NASA Reliable Electrical Connections School at the George C. Marshall Space Flight Center in Huntsville, Alabama, many years back.
Ralph, Latte Land, Washington