I have an Adler Barbour Cold Machine, two of them, in my 1994 40.5. One is for the refrigerator, the other for the freezer. They are identical; therefore, why is one compartment a frig. and the other a freezer? Also, the o-ring in the fitting at the connection to the plate (a thin, rectangular, stainless apparatus)has been damaged and I have lost the refrigerant. Where can I get replacement o-rings? Thank you for any help. Larry Baswick