[Koha] Koha outdated call number in Location field

[Daniel Glendening]

Hi,

I'm trying to convert our small library from an old outdated 
call number system to Library of Congress.

I've run into a strange situation: when I change the call 
number on a biblio record and item, for some reason 
the item won't show up with a catalog search of that
 call number. Strangely, it WILL show up with a catalog 
search of the OLD call number. Despite the old calll 
number not being present in any MARC or item record
 fields, when i run a search query it show up in the 
"Location" field, for example:

"1 Resource Room <i>Resource Room Stacks M.AE4.2006</i>

generic: 
"1 Library Name<i>Location Old-callnumber</i>

Any idea why the new LCC call numbers are not searchable, or
 why this old call number won't go away?

Thank you!

Daniel