Anti-Siphon vacuum breaker replaced

[loadmaster]

beeje: If you have any pictures of the under belly of the camper, I would like to see them. I'm getting ready to replace the probe in the black and grey tank with the new Horst Tank probe. When I check the tanks I get a reading of 2/3 full and I know for sure the tanks are empty. So if you would send them to me @ ldmaster@comcast.net that would greatly appreciated, and them I'll try and post them for you. Plus I live in Martinsburg WV just of the mountain from you, maybe we will have to get together one day and talk.
Jim

[beeje]

loadmaster, I will gladly get the pics I have to you. ASAP

[Golfmedik]

OK, riddle me this please? I've got the same vacuum breaker that you guys have shown here(brass one) to replace my CHEAP one with. Now I'm being told by another member elsewhere that the brass one does not have a "check valve" and that one should be added to the outgoing side of the valve. Says the cheap factory one does have a ball/spring combo valve that should remain. This is a setup that he recommends. What say you guys?

[Golfmedik]

If a check valve is required, would one like this Sharkbite one work?

[BB_TX]

My 2007 with a plastic anti siphon valve did not have a check valve. At least not an external check valve. Maybe a built in one? Newer models may be different.

[scottz]

My plastic one did not have a check valve. A check valve would defeat the purpose of the vacuum breaker. As I understand it, when the vacuum breaker opens it introduces air into both legs (towards black tank and towards water inlet) allowing water to drain both directions. A check valve would prevent the water from draining out one leg. If nothing else, that would cause problems winterizing. When the vacuum breaker operates properly, there is no water remaining in the lines.

[Golfmedik]

Originally Posted by scottz

When the vacuum breaker operates properly, there is no water remaining in the lines.

That is the way I always thought it worked as well....

[beeje]

There is no vacuum breaker/ check valve needed. Our fine government regulations required it to be there. The flush system works just fine without either one in place. The chances of sewage being drawn back into the fresh water system are nil to none since there is no sewage around the spray head when flushing the tank out (if you are doing it correctly). The tank should be drained first before starting the flush.

[scottz]

Originally Posted by beeje

There is no vacuum breaker/ check valve needed. Our fine government regulations required it to be there. The flush system works just fine without either one in place. The chances of sewage being drawn back into the fresh water system are nil to none since there is no sewage around the spray head when flushing the tank out (if you are doing it correctly). The tank should be drained first before starting the flush.

Agreed, but don't forget to winterize the tank flush.

[beeje]

The lines that are plumbed to my tank are all down hill. so they self drain by themselves.

[MARK A]

Originally Posted by beeje

There is no vacuum breaker/ check valve needed. Our fine government regulations required it to be there. The flush system works just fine without either one in place. The chances of sewage being drawn back into the fresh water system are nil to none since there is no sewage around the spray head when flushing the tank out (if you are doing it correctly). The tank should be drained first before starting the flush.

>>if you are doing it correctly << Is the operative term here. There are folks that think it’s ok to drizzle black tank water on the highway. “Doing things correctly”is not a given.
Mark

[scottz]

Originally Posted by beeje

The lines that are plumbed to my tank are all down hill. so they self drain by themselves.

Not if there is a check valve on the end.

[rsp]

If there is anyone out there with a Montana 2017 3810MS that knows where this valve is please let me know. I don't want to remove anything that I shouldn't. So far I haven't found it.

[MARK A]

You should be able to see from underneath probably with the basement wall removed, 2 white 1/2” pex tubes going up through the floor. It’s likely under the bathroom sink, or I've heard of them being in the shower wall.

Mark

[jcurtis934]

Mtlakejim, look under your bathroom sink. If you see four pex lines there, then two will be hot and cold water (red and blue) and two will be tied together with the plastic device that we can a vac breaker. At least that is where mine was.

[BuilderBob]

You can pull the back wall in the basement by the convinces center side and fallow the water lines for the black flush they are the white ones the should go up under the sink in the bath room if you are going to bypass them just do behind the convinces center much easier to do it right their!

Bob & Carol
Washington St
2017 352RL 2008 Dodge 3500 DRW CC LB 4x4

Happy Trails

[BB_TX]

If the anti siphon valve is not under one of the sinks it may be inside a wall. I pulled a panel in the basement so that I could see under the floor under the shower. There was a red pipe (shower hot), a blue pipe (shower cold), and two white pipes (black tank flush lines) going up thru the floor. That meant the valve was inside the wall with the shower faucet fixture as there was no other reason for those xtra lines.

Opposite side of that wall is my entry closet. There was an opening on the back wall (about 6” sq with a plastic cover) I could reach thru and feel the valve but could not see it. Had to cut a new opening lower and to the left to remove the antisiphon valve.

[footz1941]

Originally Posted by BB_TX

If the anti siphon valve is not under one of the sinks it may be inside a wall. I pulled a panel in the basement so that I could see under the floor under the shower. There was a red pipe (shower hot), a blue pipe (shower cold), and two white pipes (black tank flush lines) going up thru the floor. That meant the valve was inside the wall with the shower faucet fixture as there was no other reason for those xtra lines.

Opposite side of that wall is my entry closet. There was an opening on the back wall (about 6” sq with a plastic cover) I could reach thru and feel the valve but could not see it. Had to cut a new opening lower and to the left to remove the antisiphon valve.

Cut them in the basement if you can get to them. Remove or replace down there

[scottz]

Originally Posted by footz1941

Cut them in the basement if you can get to them. Remove or replace down there

x2. The instructions with the brass vacuum breaker I installed said it only had to be 6" above the tank. Mine is is in the open under the bath sink, so I left it there. My previous camper had it inside a will; I cut the pipes and relocated it to the basement.

[greenmachine]

i'm next, just ordered the fittings. also i'm one of the lucky ones, no leaks to date and the fitting is under the bathroom sink in our 2014, 305rl HC.