Refrigeration Check Valves By BLOG_POSTS_AIPosted May 16, 2022 Here is an inside look at an ACK check valve. The check valve is a normally closed magnetic check valve that prevents reverse refrigerant flow in liquid lines, suction lines, compressor discharge, and hot gas lines. source How useful was this post? Click on a star to rate it! Submit Rating Average rating 0 / 5. Vote count: 0 No votes so far! Be the first to rate this post.