We've had our black tank plugged several times. The fix is super easy. You don't need to call anybody. You don't need to disassemble anything. As mentioned in a previous post, just install this device:
Flush valveYou simply attach this to the drain pipe on your RV, close the gate valve on this device, open your black tank valve (keep gray tank valve CLOSED), attach hose and turn the hose water on.
This will push water back up into your black tank and unplug the pipe. It takes a little while for the water to fill the drain pipe and get back up into the black tank. Maybe 1 minute or so. After one minute, shut the water off and open the gate on the flush valve. If the black tank doesn't start emptying, run more water through the hose.
It sounds way more complicated than it is but it's super simple and gentle on the plumbing. You are just pushing water back up against the solids that are plugging the pipe at the tank. If the gate valves on your RV are working properly, the device is 100% guaranteed to work. I keep one attached to my RV all the time just in case I get a blockage. As an added benefit, it prevents fluid from leaking out when you remove the sewer cap.
