I have a Bauer Mariner II compressor equipped ith an ACD system. The PLC (electronics) are programmed to drain the system every 15 minutes. Recently I noticed that the system is not draining on its own. I replaced the solenoid kit, but the system is still not draining. I checked the wiring at the PLC and there is voltage going to the system. The system lights on the PLC are lit for on the 0,i,2,3 for the "in" part of the PLC and 0, 1, 4,5 on the "out" part of the PLC. The power indicator light is lit, the run indicator light is lit, the error light is not lit, and the stat light is blinking on and off. I have to admit I know knothing about the PLC. I cleaned the electrical contacts going to the ACD. The system does drain when I turn the compressor off and the second stage pressure falls below 300 psi. I have a couple of quick questions: 1. What could be causing the system not to self-drain while the compressor is running? 2. Is there any way I can continue to operate the compressor by manually draining the system, and if so how is this done (do I have to turn off the compressor, wait until the system drains when the second stage pressure declines to 300 psi)? Thanks in advance for any information!