Black tank flush vacuum breaker.

[Beachcamper]

Finally after 4 months on the road, I have found a campground with good internet to catch up on RV YouTube videos, Changing Lanes had an issue with a water leak that stumped them. Finally figured it was the vacuum breaker. The coroplast had to be removed and insulation dried out. It was a chore, I got to thinking…should I replace my vacuum breaker with the brass one I have ready in case of such an emergency? Or just do the replacement when and if OEM one fails? Thinking this could be yet another project when I get back to Florida in October.

Here is Chad dealing with the problem:

https://youtu.be/08dJ9GK-1h4

[Superduty]

Hi Vivian,
If this was me, I would change it out. The ones that are on the our camper are junk. By the time you realize they are leaking, the mess is already there.
This was one of the first things I did when we got out 5er home, before even using it. Pretty simple to do.
Pull the facuet cover off in the shower, and take off the old, and replace with the new. (This is where mine was located, and your should be also)
Just in case, shut the water off to the trailer. I think do to the room for my hands, I took the handl hot/cold lines off. These all are twist on fittings.

Steve

[Beachcamper]

Superduty did you replace with the same or did you use the same Watts brass one like the one I purchased? Yes, I have been in this area to check out how plumbing feeds the faucet and to look at the vacuum breaker location in years past. I am attaching a picture of where it is for anyone else who has a 303rls. It is behind the towel rack at faucets. Unscrew @ the corners and remove, obviously make sure to have silicone on hand to apply all around when done.


Were you brave enough to replace the soft hose while in there?

[Superduty]

Same "watts brass valve" that you have. The plastic ones that come on the trailers are just junk.

Soft hoses. I have not gotten that far, but I'm keeping an close eye on them until I do replace them. This is planned for this year after we were done camping for the season and ready to put the 5er up for the winter hibernation.

[Beachcamper]

I have replaced soft hoses feeding the water heater but the ones in the shower area are not going to be on my list. They connect behind the furnace a very difficult area to get into. Still working on courage to do the toilet feed from above the converter. Maybe the day the converter goes, I will go ahead and tackle that one as well.

Meanwhile, will take your advice and get the vacuum breaker replaced when back on my seasonal lot.

[Superduty]

Yea, the space to work on these rigs is not fun, especially in the basement area.
I also dread doing this conversion, but water damage is no fun at all.

[Cate&Rob]

Beachcamper Superduty
Hi Vivian & Steve:

A caution on what you are doing here . . . the OE device is a vacuum breaker / check valve and the brass one is just a vacuum breaker. In "theory" the contents of the black tank could be pushed into the brass device and either out its vent holes or back to the intake connection. Either one will drip leak if fed with very low water pressure (like a hose left connected and turned off but laying in the sun). The location in the 303 is poor for a couple of reasons. One, is hard to get at and two, it is over the furnace which will get wet when it drips.

Rob

[TedS]

The Watts device does have a check valve to prevent backflow.

From Watts: Description

This 1/2 inch lead free anti-siphon vacuum breaker for hot or cold water prevents the reverse flow of polluted water from entering into the potable water supply due to backsiphonage. It consists of lead free construction, chemical resistant silicone seat disc, chrome hood, and an atmospheric vent to prevent spilling. It has a full size orifice to assure pipe size capacity and maximum flow. It is ideal for low flow, non-continuous hot or cold water health hazard applications such as on laboratory equipment.

[Beachcamper]

Beachcamper Superduty
Hi Vivian & Steve:

A caution on what you are doing here . . . the OE device is a vacuum breaker / check valve and the brass one is just a vacuum breaker. In "theory" the contents of the black tank could be pushed into the brass device and either out its vent holes or back to the intake connection. Either one will drip leak if fed with very low water pressure (like a hose left connected and turned off but laying in the sun). The location in the 303 is poor for a couple of reasons. One, is hard to get at and two, it is over the furnace which will get wet when it drips.

Rob

Thanks for chiming in Rob. Well this is not a good scenario then for using the brass Watts. Guess I will leave what is there and order another OE type in case of a mal function down the road. Will also add another water alarm to this area by the furnace.

I would assume a leak would only occur if using the black tank flush? I never leave any hose other than city water to nautilus on and turn water off if I leave rig. However, that check valve scenario is a worry.

[JCR GD]

When I replaced mine I bought the brass vacuum breaker AND a inline check valve to go with it. Both available on Amazon.

[Jlawles2]

Cate&Rob Superduty and Vivian,

Looking at the watts website and the specifications for https://www.watts.com/products/plumb...m-breakers/715 it does not show a spring to close the check valve.

Looking at https://www.watts.com/products/plumb...kers/710-febco it specifically calls it a backflow preventer. Again no spring.

Then I found this one https://www.watts.com/products/plumb...breakers/lf289 that has a spring which will prevent water from pushing through from the black tank side. Note it also has a nice vent seal to keep any water from pushing through the valve.

[TedS]

It looks like the check valve is on the inlet to prevent backflow into the inlet. There is no check valve on the outlet, so any back flow will exit the air vent. But there should be no backflow when the valve is above the toilet rim.

[Superduty]

The Watts device does have a check valve to prevent backflow.

From Watts: Description

This 1/2 inch lead free anti-siphon vacuum breaker for hot or cold water prevents the reverse flow of polluted water from entering into the potable water supply due to backsiphonage. It consists of lead free construction, chemical resistant silicone seat disc, chrome hood, and an atmospheric vent to prevent spilling. It has a full size orifice to assure pipe size capacity and maximum flow. It is ideal for low flow, non-continuous hot or cold water health hazard applications such as on laboratory equipment.

Rob,
Agree with what you mention between the two types of valves. Vivian, could add a check valve on the other side to prevent back up from the black tank as TedS I think mention.

One thing I remember is always use full water pressure. These valves do not like low pressure (leak).

Steve

[Beachcamper]

Well dang! That vacuum breaker with check valve Joseph posted is pretty expensive! I do have a check valve and can add it as in pic posted by Jim. BTW I checked my old Amazon order for the brass one and I paid $28 back in 2019.

[TedS]

Beachcamper it is described as being spill-resistant which would be a plus for inside installation that should not get wet.