1987 325 (not i model) has working a/c conversion. There is a tiny leak apparently that needs a refil(?) or recharge every 4 years.

I had that done and the belt replaced as it was torn. Worked fine for a few weeks.

Yesterday, the fan stopped working - 90s outside so i checked fuses 3,18 and 20. 20 was blown. Replaced. Fan starts again and A/C is blowing cold for about 15 mins.

Goes out. Drove for 2 hours. Never came back on. Fan still blows. Fuses are fine. The recirc button lights up yellow but snowflake doesnt activate. Does this mean the button is broken?

Any ideas? I know a little car talk but not a lot so please try to use simple explanations for when I go get help.