87 300sdl I converted last year to 134. It worked fine until now. I am getting hot air blowing constantly with ccu off. I checked fuses and found #5 blown. I replaced it and hot air stopped blowing. I checked ac low pressure line and have no pressure. I also can see the compressor will not engage. I can manually move the clutch, so apparently it is not frozen. What would you reccomend I check? Is there a punchlist or a procedure to follow to repair ac? Any help will be appreciated.