Update-Leaky Black Flush Vacuum Brake

[Oemtech]

Well last night I walked around the rig and saw a "BIG" puddle of water just behind the the rear wheels. I thought I forgot to empty the gray tank again... When it is "really" full the gary tank leaks around where the vent pipe goes into the tank, even with sealant putty installed. I checked the tanks and they were both empty.

As I checked further, the water was dripping off the "pex" pipes coming from the bath room. Oh, great a cracked "pex" pipe that I can't get to. I went into the bath room and sure enough the floor under the sink was wet. As I was checking the pipes I felt a drip of water. Low and behold the water was run down a pipe. After checking I found that the "check valve" was leaking. I shut off the water, removed the valve, cleaned it, checked for proper operation, reinstalled it, turn on the water and checked for leaks. No leaks... Hurray. Recheck 20 mins later, water on the floor. Turned off the water and went to bed.

Saturday morning I called the dealer and sent photos of the needed part. I will call Newmar Monday to find out just exactly what this thing does.





Now I needed to repair it so I can use the the rig... as I live 24x7x365 in it. I couldn't find a 1/2" male/male pex elbow. So, I took a 1/2" pvc threaded elbow, a short piece of 1/2" pvc pipe and 1/2" treaded straight to make the fitting I needed.



Installed my make shift adapter, I now have water and no leaks.

On Edit:
This item has been federally mandated on all RV's with a black tank flushing system since about 2004.

[Oemtech]

Well last night I walked around the rig and saw a "BIG" puddle of water just behind the the rear wheels. I thought I forgot to empty the gray tank again... When it is "really" full the gary tank leaks around where the vent pipe goes into the tank, even with sealant putty installed. I checked the tanks and they were both empty.

As I checked further, the water was dripping off the "pex" pipes coming from the bath room. Oh, great a cracked "pex" pipe that I can't get to. I went into the bath room and sure enough the floor under the sink was wet. As I was checking the pipes I felt a drip of water. Low and behold the water was run down a pipe. After checking I found that the "check valve" was leaking. I shut off the water, removed the valve, cleaned it, checked for proper operation, reinstalled it, turn on the water and checked for leaks. No leaks... Hurray. Recheck 20 mins later, water on the floor. Turned off the water and went to bed.

Saturday morning I called the dealer and sent photos of the needed part. I will call Newmar Monday to find out just exactly what this thing does.





Now I needed to repair it so I can use the the rig... as I live 24x7x365 in it. I couldn't find a 1/2" male/male pex elbow. So, I took a 1/2" pvc threaded elbow, a short piece of 1/2" pvc pipe and 1/2" treaded straight to make the fitting I needed.



Installed my make shift adapter, I now have water and no leaks.

On Edit:
This item has been federally mandated on all RV's with a black tank flushing system since about 2004.

[GaryKD]

Congrats, you deserve it.

[Max Hubrich]

Hi Dale,

I just checked mine. I don't have the same setup. Mine is a straightforth hot/cold hook up for both the bathroom sink and the clothes washing machine. No other lines under the sink-- What in the world could this valve be for?

[Brigadoon]

Dale,

I'll be interested in hearing what Newmar has to say. I've been thinking of doing the same. A tech that I talked to says that is tied in with your black tank flush system. I asked him if it was necessary, he said probably not but there are some builing rules/regulations that say builders have include that valve in their design.

I'm also think of capping off the black pipe that is visable in your pictures. Both pipes have been known to leak oders out into our bathroom.

[Oemtech]

I kind of figured it was something like that. For about a year I have heard water dripping after I emptied the tanks. I just assumed that it was my RO system kicking in. But, after I added the "check valve" bypass the dripping stopped. I am not sure but I think the water was actually running into the GRAY tank as it would fill like 2X faster that what I thought was normal.

A couple things I forgot to add to the original post.

1) Always turn off the water if you are going to be away from the rig for more than a hour. Believe me a small drip can ruin your day.

2) Turn off you water heater (both propane & electric) or you just may find a burned up water heater or worse a burnt coach. Why, when you turn off the water the system will depressurize over an hour or so and the water heater will release enough water that allow part of the electric element to be exposed. Now as the water cools the thermostat will call for heat and the heating element will not be under water completely. Now should you have the propane switch on you could end up with a real mess.

OBTW - My total cost in parts for the bypass was $1.60. But, even if I add in the glue, the small piece of pipe, the trip to town and my time I might have $5 invested and 2 hours total time. But, if i had the dealer do it I would have at least 2 days assuming they had the part in stock, $225+ in gas (6 hour round trip) and $150? parts/labor.

[Oemtech]

I spoke to Newmar.... Brigadoon was right.
1) It is Federally mandated... So, it probably applies to all brands and models.
2) It is placed up high so that gravity and air pressure will make the valve function correctly.
3)Not sure if it drains into the gray tank.
4) I am not the first person to get have this problem and my bypass is pretty much normal.

[Route 66]

It's a back flow prevention valve for the black tank flush.

[Oemtech]

Call it what you want... It is installed in a very poor location. When it fails you get lots of stuff wet.

I have an anti back flow preventer on my system that drains into the bay where the sewer connection is. I can collect a full 8 oz. plastic cup of water when I turn off the black tank flush. That much water drained under your bathroom sink can ruin you day!

[Latitude]

Its like "this"

Its under the sink beside the shower!!!


Rick

[Oemtech]

That would be the part to keep an eye on.

[Oemtech]

UPS delivered the replacement part... Newmar's cost $45. But, I think the part may have originated in Austin, Tx..... Yep, about 45 mins from my house. I will check this out in the morning.

[Oemtech]

I got hold of the manufacturer... This is his 1 and only product. You can get the replacement part shipped via USPS to you door for $17.

Newmar/Dealer/UPS Shipping = $52.47
Lakeview RV Supply/USPS = $17.00
Difference <span class="ev_code_RED">$35.47</span>

Should you need one:

Lakeview RV Supply
512-261-8000

[Brigadoon]

Thanks Dale, I'll keep this info in my file.