fleetwood grey water drain problems

dougrainer wrote:
Thru the roof vent by running water down thru it from the roof is NOT always a good check of venting. It depends on how FW plumbed the system. They sometimes run vent AND drain plumbing 1.5 inch pipes thru the same wall connection. Ideally, you have the sink/shower 1.5 inch drain pipes run to the tank and then the 1.5 inch vent stack pipe is seperate and goes up thru the roof. But, they don't always do that (run a seperate vent stack pipe. Also, IF the roof vent stack pipe is inserted INTO the top of the tank and DOWN TOO FAR, then it may not vent air correctly(this is what is indicated by leaving the Gray valve open and the sink drain normally). I would see if you can go on the roof and see if you can pull the roof top pipe UP a little bit. If so, then retest. Doug