Problem with langage encoding

I've inherited a database system (including source)... It's Russian text
(which I don't speak, but I need to work on it).

On my screen it shows correctly, but in the database it shows a mess...
from trying with a web browser. It appears that the data in the database is
encoded with ISO-8859-1 (my browser and the database viewed with PGAdmin
match when my browser has ISO-8859-1 encoding).... and it shows correctly
on screen in my browser when I use the WIN1251 encoding...

The problem is that the database is UTF8, and it won't let me use the
convert_to function because it says that the characters don't exist... What
I need to do is to pull the UTF8 from the database, tell postgres that it's
8859-1, and then convert it to WIN1251... How?

Thank you for any assistance!

Ron