Black tank flush

[Preadus]

I just tried to use the black tank flush for the first time. Is there some sort of trick? The water will not flow into the tank.

[Campin Cajun]

There should be a check valve somewhere along that water line. Yours might be installed backwards. I'm not familiar with the wetbay on that model, on my Berkshire the access is on the PS and I can see the black tank there. The washer is held on by three screws, if yours is the same take the screws out, pull the washer out and see if you are getting water to it.

[bubbles]

I have a GT378 and the backflow valve is in the washing machine provisional area and zip tied to the plumbing for that washer. If you have emptied your black tank before and not ran water thru the cleanout the nozzle for that cleanout may be cloged with tank residue. If you locate the backflow valve and it's a clear one as is mine you will see how it is supposed to operate. It's just a simple water pressure switch.

[Iggy]

Looks like this inside one of the bedroom closets and may be behind a piece of wood panel. Usually close to where the washer dryer is hooked up at.

[k3wtf]

I have the same issue. Did you ever correct yours?

[Texas Peddler]

This is a Vacuum Breaker required by Code to prevent the possible siphoning of contaminated liquids back into the water supply. If the Breaker is installed with the bonnet in the up position, it should work as designed and allow water to flow into the dark water tank.

[Preadus]

I have a scheduled repair. I'll let you know what they say.

[Mark S]

How fast should water flow into tank? Mine goes in but seems like a seems slow, not like when I use the discharge valve flush. Should water trickle out of the tank when flushing or a fast flow?

[Scagsdale]

I tried the black tank flush on my last trip....I have a new GT 328. If you just plug the hose in, have the black tank valve open, and turn on the hose, the water comes out in a steady stream, but without the large "swoosh" that you get when you open that big valve with a full tank. I closed the valve, let the tank level build up, and then opened the valve. I did that a few times, then I turned off the flush hose, closed the black valve, and opened the grey valve. I don't know if I did it exactly correctly, but it seemed to work.

[ramair]

that's the way I flush mine. I do this until clear water only comes out.

[bubbles]

Originally Posted by Mark S

How fast should water flow into tank? Mine goes in but seems like a seems slow, not like when I use the discharge valve flush. Should water trickle out of the tank when flushing or a fast flow?

Have water flowing thru the cleanout port and open the blackwater valve and allow tank to empty down to just the slow stream from the cleanout. Close the blackwater valve and allow the cleanout input to fill your tank (you can see peogress with a flashlight shined down the comode and your tank level indicators). It will take quite a long time to fill your tank (the water does not rush in). Then open the valve again and this should empty your tank of all contents and keep your indicator sensors and tank clean. If the water does not run clean at the end of the big dump, repeat as necessary. Now, this should be done at your camp site sewer connection because it takes to long at the community dump site and there will be alot of p-o'd campers. I know someone is going to comment on this input due the closing the valve with water running in but the tank is vented and it is not an issue (google for cleanout procedures).