Sewer Outlet Pipe Release Valve??
Has anyone ever installed a pressure release valve into their sewer pipe?
Here’s the issue...
I mainly travel in the west these days... constantly changing altitudes as I make my way back & forth around the Rockies. With these changes in altitudes come vastly different temperature & air pressures from one location to another. Let’s take my latest move as an example...
Before finally leaving my winter camp in Arizona, I dumped the black & grey tanks. I even kept the drain valves open for an extended period (15-20 minutes, or so) to get them as empty as possible. No issues... and when I removed the sewer hose from the rig, nothing was draining from the outlet.
So I get on the road and begin traveling to my next destination, which happens to be at a location significantly higher in altitude than my previous one. I was around 800’ MSL on the Colorado River in Arizona... and am now at 5,100’ MSL here in Wyoming, but traveled as high 8,200’ MSL during transit.
Now, even though I allowed those tanks to fully drain earlier... I know that due to the normal jostling on the rig during travel that I might find some fluid had seeped into the outlet pipe once I arrived. And, having experienced the following before, I was prepared for it.
When I went to connect the sewer hose to the rig... and I begin removing the cap... BOOM! The pressure inside the pipe literally blew the cap off as soon as the cam locks were released... spewing all of those residual liquids out at high speed from the outlet.
Like I said... it’s happened before, so I knew to be well out of the way.
I understand why it happens, as with the black & grey tank valves closed during transit, there’s no venting available for the pipe... but I figure there’s gotta be a way to keep that from happening.
I’ve thought of leaving the 2nd grey tank valve open during transit... but again, with the jostling of the rig rolling down the road, I figure even more grey water that maybe didn’t fully drain while sitting static could end up in the pipe upon arrival.
Which then leads me to the question posed: has anyone ever installed, or heard of anyone installing, a pressure release valve into the 3” sewer outlet pipe?
I did a cursory search on Goggle, and on another RV forum... and the only release valves discussed were for the water heater, and other assorted fresh water systems.
So just curious... any ideas?
2013 VOLTAGE 3200 (EPIC I & II)
2014 Ford F-450 PLATINUM