Go Back   Montana Owners Club - Keystone Montana 5th Wheel Forum > MOC on M.A.R.S. > Repairs & Service
Click Here to Login

Reply
 
Thread Tools Display Modes
 
Old 08-30-2019, 10:47 PM   #1
Ohioken7
Established Member
 
Join Date: Apr 2019
Location: Rossford
Posts: 30
M.O.C. #23846
What is this under my sink? Itís leaking

Found this, the black valve thing connecting the white lines, leaking tonight. What is it? Hopefully the photo I attached works. If not, on my MHC 372rd we have dual sinks. On the right side, a white pex line comes up from the floor, connects to a black valve thing, then back to the white valve.
Attached Images
File Type: jpg B2380038-D41A-4CFB-B1FF-3CF34313DC4C.jpg (255.3 KB, 16 views)
__________________
Ken & Margaret
2019 372RD
2019 F450
Ohioken7 is offline   Reply With Quote
Old 08-30-2019, 11:26 PM   #2
Carl n Susan
Site Team
 
Carl n Susan's Avatar
 
Join Date: Oct 2005
Location: Carmichael - CA
Posts: 4,098
M.O.C. #4831
That is an anti-siphon valve for the black tank flush.
__________________
Carl (n Susan) Youngren
There is more to life than fuel mileage.
2012 Montana 3700RL Big Sky Package towed by a 2015 Ford F350 6.7L PSD 4WD CC LWB

Carl n Susan is offline   Reply With Quote
Old 08-31-2019, 06:38 AM   #3
Mikendebbie
Montana Master
 
Mikendebbie's Avatar
 
Join Date: Jan 2018
Location: Austin
Posts: 556
M.O.C. #21044
Anti siphon valve

Question: I assume since I have 2 black tanks with separate flush systems - I have two anti siphon valves- correct?
__________________
Mikendebbie Austin TX - Aggie '77
2019 Chevy 3500 High Country DRW
2018 Montana 3921FB
Three cute Aussies Gus+Fern+Jimmy
Mikendebbie is offline   Reply With Quote
Old 08-31-2019, 09:12 AM   #4
BB_TX
Montana Master
 
Join Date: Oct 2006
Location: McKinney
Posts: 5,303
M.O.C. #6433
Ken - Those black tank flush anti siphon vacuum breaker valves have a long history of leaking, often to the point of flooding your trailer. Many have simply removed them and connected the lines directly together, and use an external anti siphon valve. Some don't even use an external valve. The chance of dirty water being siphoned back into the public water supply is very remote in this case, but remote does not mean impossible.

Some have replaced the valve with a better quality brass valve.


MikenDebbie - I would think if you have two black tanks each having a flush connection that there would be two of those valves. One valve could not service both flush lines since each has its own connection.
__________________
Bill & Patricia

2007 3075RL
2012 F350 SRW CC LB FX4 6.7
BB_TX is offline   Reply With Quote
Old 08-31-2019, 09:20 AM   #5
Ohioken7
Established Member
 
Join Date: Apr 2019
Location: Rossford
Posts: 30
M.O.C. #23846
Thanks everyone for the advice.
__________________
Ken & Margaret
2019 372RD
2019 F450
Ohioken7 is offline   Reply With Quote
Old 01-12-2020, 09:49 PM   #6
Theater Effects
New Member
 
Theater Effects's Avatar
 
Join Date: Oct 2019
Location: SL, UT
Posts: 7
M.O.C. #25168
Sorry old thread. Does this only leak when you flush the tank or are there other times it could leak?

Obviously if it leaks replace/fix as indicated, but just wondering if it limited to only when you flush the tank.
__________________
2017 F350 SRW
2019 MHC 372RD
Theater Effects is offline   Reply With Quote
Old 01-12-2020, 10:40 PM   #7
Daryles
Montana Fan
 
Daryles's Avatar
 
Join Date: May 2019
Location: Alton
Posts: 335
M.O.C. #24086
If it is defective, and you have a fairly full black tank, and you corner at speed, it is possible for the water to slosh with enough pressure to backflow.
Hence, why it is mounted high above the tank and why it is an anti-siphon, one way valve.
Cash ACME brass 1/2" FNPT anti siphon vacuum breaker valve.
https://www.lowes.com/pd/Cash-Acme-B...ker/1000385647
__________________
Daryl
Daryles is offline   Reply With Quote
Old 01-13-2020, 08:59 AM   #8
BB_TX
Montana Master
 
Join Date: Oct 2006
Location: McKinney
Posts: 5,303
M.O.C. #6433
Quote:
Originally Posted by Theater Effects View Post
Sorry old thread. Does this only leak when you flush the tank or are there other times it could leak?

Obviously if it leaks replace/fix as indicated, but just wondering if it limited to only when you flush the tank.
That valve is only connected to the flush water line connection in the convenience center and is never pressurized unless you open the water faucet valve to it. It is not connected to any other source of water.
__________________
Bill & Patricia

2007 3075RL
2012 F350 SRW CC LB FX4 6.7
BB_TX is offline   Reply With Quote
Old 01-14-2020, 07:30 PM   #9
beeje
Montana Master
 
beeje's Avatar
 
Join Date: Oct 2015
Location: westminster md
Posts: 1,366
M.O.C. #17894
Quote:
Originally Posted by Daryles View Post
If it is defective, and you have a fairly full black tank, and you corner at speed, it is possible for the water to slosh with enough pressure to backflow.
Hence, why it is mounted high above the tank and why it is an anti-siphon, one way valve.
Cash ACME brass 1/2" FNPT anti siphon vacuum breaker valve.
https://www.lowes.com/pd/Cash-Acme-B...ker/1000385647
#1 You should not be traveling ANYWHERE with any substantial stuff in your tanks...Ö.
#2 There is NO way for it to back flow to anything, since there is a check valve at the hose connection to the flush system.
__________________
2014 GMC 3500 Dually diesel 4x4 CCLB. Curt q24.
2011 Montana 3455 SA. 6 point level up. Disc brakes.
Progressive EMS. Valterra tank valves. Sailun G637 tires. ARP fridge control. All led lighting. Mor Ryde IS to be installed 6/2020
beeje is offline   Reply With Quote
Old 01-17-2020, 12:48 PM   #10
lundwc16
Montana Fan
 
Join Date: Oct 2015
Location: Aquebogue
Posts: 112
M.O.C. #17988
Removed my anti siphon valve after a leak. I ran a direct line from the black tank flush & added a anti siphon valve used on lawn sprinkler systems from a big box store. I am surprised to see an anti siphon under a sink, as I was told that it should be higher than any other drain in the camper to meet "code". From the factory mine ran from the basement up behind a wall higher than the shower drain.

John
__________________
2010,3075RL, Hickory
2016 Ford, 6.7, 4X4, SRW
lundwc16 is offline   Reply With Quote
Old 01-17-2020, 01:47 PM   #11
BB_TX
Montana Master
 
Join Date: Oct 2006
Location: McKinney
Posts: 5,303
M.O.C. #6433
Quote:
Originally Posted by lundwc16 View Post
..........
I am surprised to see an anti siphon under a sink, as I was told that it should be higher than any other drain in the camper to meet "code". From the factory mine ran from the basement up behind a wall higher than the shower drain.
John
That line is only connected to the black tank flush. Since the black tank is under the floor it only needs to be higher than that to function correctly.
__________________
Bill & Patricia

2007 3075RL
2012 F350 SRW CC LB FX4 6.7
BB_TX is offline   Reply With Quote
Reply

Tags
leak, valve sink

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Montana RV, Keystone RV Company or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 05:17 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×