AC turns on/blows but no cold air.Also a strong chemical (NOT a moldy) smell.

What is your question?

I took it to be repaired. They added a/c coolant & I had cold air for 2 weeks- still with the chemical smell. Also began hearing a hissing type sound (like air leaking) when ac was first turned on & right after it was turned off. (This sound was not there before). After 2 weeks, same problem: air blows, but no cool air. No more chemical smell. Mechanic now says it is the condenser unit (?) Mechanic said he tried to put it on a diagnostic computer to see about a leak, but that the computer would not let him get that far due to the condensing unit not working.