11-28-2023, 08:40 AM
I am having the same issue with mine, I can hear air flowing through the intake hose of the engine driven air compressor. This should be stopped at the air dryer as it has a check valve of sorts that keeps the air from flowing back to the compressor. I believe that Richard is correct, this is a part of the purge valve on your air dryer, you can either rebuild the purge valve or replace the entire unit. I have a newer Wabco 1200 air dryer but my coach is a bit newer. I have a new purge valve to put in mine to see if it cures the issue but have just not gotten to replacing it yet.