Dryer Purge Valve and Primary Tank

Did you replace the check valve. ????

 

10/4 . I just recently had to work on my dryer and if I remember right, I had some trash in the system due to me not being carefull enough when I went to put it all back together...But I took it all back apart and cleaned the check valve up really good and walla problem solved...May or may not be your problem but it doesn't hurt to try, doesn't cost anything and who knows, just make sure that you have some extra o-rings in case you mess one up....Just thought I'd throw that out there..

 

Ok, you are positive the tank is actually empty, and not just a bad gauge? Did you remove the line at the drier and make sure air is not coming out at all? Anyway, I agree with waybrot, before replacing it see if you can take out the pp valve and clean it. I have never done that, but don't see why it can't done. There are also two auxiliary ports, if one is not used you should be able to supply that other reservoir from there.