Emptying Dual Black/Grey tanks

[GWRam]

We are heading out on our maiden voyage in our Gateway 3650BH today. Having dual black and gray tanks is new to me. I have been wondering what
is the best way for emptying the tanks. One drain pipe from camper to sewer moving the pipe from front to back valves as needed? Two drain pipes to a
Y fitting and then to sewer? If using a Y fitting do I want to have the Y just before the sewer or up close to camper?

What have you found to be the best and or most efficient way to set this up?

Thanks for your ideas

Dave

 

[marvmarcy]

If moving often, one hose is less to store and rinse. Dump the black first, then rinse out with gray, followed by some fresh water from a garden hose (not your water fill hose).

 

[MCTalley]

When parked long enough to utilize the sewer hookups, I'll generally leave the rear gray tank hooked up and open (kitchen). Every few days, I'll close that valve and move the hose to the front hookup, flush and dump the black tank, then follow up with the front grey tank (bathroom). We've found we can easily go a week on the front tanks, so I plan accordingly.

That said, I did buy a "Y" and used it once, but makes for a lot of hoses stretched out alongside the coach. Since I don't leave the front grey or black tank valves open all the time, it was a lot of unnecessary plumbing to carry around.

 

[TXTiger]

If you need to have all your tanks hooked up to a sewer at the same time I would use short hoses from each tank to a Y connector and then one long hose to the sewer connection. That way you only have one long house to clean and store.

 

[danemayer]

Get an external gate valve for each sewer outlet, and one clear adapter. Then you can dump one tank, close the valve, move the clear adapter and hose to the other one and dump that tank. Or for the best value, just get two combo units. Here are links:

External gate valve
Clear Adapter with back flush
Combined external gate valve/clear adapter with back flush

 

[GWRam]

Thank You for all the information and quick responses. I will research those links provided when sitting around the campfire in a few hours.

Dave