1994 Mercury Tracer Q&A

1994 Mercury Tracer Question: When I turn on my defroster , I hear a loud noise in my engine compartment .

I have been told that it could be my air conditioner compressor,but I hear the noise when I turn on my defroster or air circulation . Is the air compressor required for all air functions? -
Answer 1
The AC compressor does run in defrost mode, so you may have been told right! Hear it in floor mode? -