Just purchased a like new 2014 Thor Ace 29.2 and in looking at owners manual regarding the black and grey tank draining it is not real helpful. Is there anywhere I can get photos or diagrams of what I need to identify and how to use ?
You might try calling Thor with your Vin number, do not know if they keep the info for a 2014. My 29.3 waste valves are in a drivers side cabinet. Each tank has its own valve, the black pipe is a larger diameter then the Grey. Each valve has a pull handle that opens the "knife type" gate valve. Hook up your sewer hose and let it rip.
Retired and never looked back