[[email protected]]

I have been looking at this problem for a year.
I finally figured it out! I have no hair left.
The remote control unit is fried. It controls the manual switch too.
The system is suposed to push the sewer hose out with compressed air and retact it with vacuum.
After reviewing the system I found this:
My coach had the extenstion valve (out pressure) with a bad solenoid but no vacuum source.
It appears the vacuum system has been removed and the port closed. I don't know if it was ever there.
I tested the extend / retract function using a shop vacuum and the air pressure port and the hose will extend and retract.
I have redesigned the system to remove the power operated sewer valve thet provides a seal so the system can create a vacuum to retract the hose.
I replaced the missing vacuum system (I assume it was simular to the slide seals system) with a centrifical 12 volt pump.
I put a N/C valve on the output of the vacuum pump so the pressure can extend the hose and not go past the pump
I put a N/C valve on the pressure output

Extend:
The remote control button is held down to active the pressure / Extend function by opening the pressure valve
when the remote button is released the valve closes
Retract:
The remote control button is held down to active the Vacuum / Retract function by turning on the Vacuum pump and opening the valve
when the remote button is released the vacuum pump turns off and valve closes

I will draw up a flow chart if anyone is interested.

It should be easy to retro fit any waster master system with hose that goes thru the tank.
It's not a big deal, but when working will be really cool.