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Standpipe Vents [message #347284] Tue, 03 September 2019 15:43 Go to next message
Rich Kinas is currently offline  Rich Kinas   United States
Messages: 113
Registered: July 2019
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Senior Member
Hey all,

While I am working on the interior and roof, I have to do some work on the standpipe that vents the bathroom sink, the pipe that snakes up beside the frig . So I was looking at it and wondering something. I understand why this standpipe is needed base on the original design layout where the bathroom sink trap ties into the bathroom standpipe then about 6 inches below this "T" the pipe travels over to the toilet standpipe and "T's" into that pipe. However I was wondering if I just ran the bathroom sink trap output directly to the toilet standpipe "T" shouldn't this work just as good? This would allow me to remove the existing sink standpipe and a lot of extra pipe, and allow me to reclaim another 4 inches of space between the bathroom module and the frig module. Also it allows me to close up another roof penetration point Smile

Thanks again...


Rich Kinas 1976 Elaganza II Orlando, FL
Re: [GMCnet] Standpipe Vents [message #347289 is a reply to message #347284] Tue, 03 September 2019 18:19 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Rich,

One little problem you may encounter with combining the bath sink vent with
that for the toilet is not immediately obvious: During long idle periods,
the sink trap will tend to dry out. That may allow noxious odors into the
coach. You may be conscientious enough to periodically refill the trap, or
to always fill it with a non-evaporating antifreeze or similar, but most
probably aren't.

One thing you may want to consider while doing all that plumbing is the use
of the newer "traps" which don't require water and occupy less space than
the older J-traps. I'm giving you advice here about something I don't have
any personal knowledge about though -- someone here can probably offer
experience.

Ken H.

On Tue, Sep 3, 2019 at 4:44 PM Rich Kinas via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Hey all,
>
> While I am working on the interior and roof, I have to do some work on the
> standpipe that vents the bathroom sink, the pipe that snakes up beside the
> frig . So I was looking at it and wondering something. I understand why
> this standpipe is needed base on the original design layout where the
> bathroom
> sink trap ties into the bathroom standpipe then about 6 inches below this
> "T" the pipe travels over to the toilet standpipe and "T's" into that pipe.
> However I was wondering if I just ran the bathroom sink trap output
> directly to the toilet standpipe "T" shouldn't this work just as good? This
> would
> allow me to remove the existing sink standpipe and a lot of extra pipe,
> and allow me to reclaim another 4 inches of space between the bathroom
> module
> and the frig module. Also it allows me to close up another roof
> penetration point :)
>
> Thanks again...
> --
> Rich Kinas
> 1976 Elaganza II
> Orlando, FL
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Standpipe Vents [message #347294 is a reply to message #347284] Tue, 03 September 2019 20:32 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
Senior Member
Here is another way of handling the drain traps. Does a nice job of making more usable space under sinks. JWID

http://www.gmcmhphotos.com/photos/g6929-sink-trap.html


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Standpipe Vents [message #347300 is a reply to message #347284] Wed, 04 September 2019 05:39 Go to previous messageGo to next message
Rich Kinas is currently offline  Rich Kinas   United States
Messages: 113
Registered: July 2019
Karma: 1
Senior Member
Ken, I did think about the trap drying out, but figured this would be no worse than I have right now, since if the sink trap dries out there is a direct open air path to the black water tank, currently.

Larry, good idea on moving the trap to the back wall to provide more usable room under the sink.

Rich


Rich Kinas 1976 Elaganza II Orlando, FL
Re: Standpipe Vents [message #347303 is a reply to message #347300] Wed, 04 September 2019 08:17 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
Messages: 769
Registered: April 2015
Location: Bell Buckle, TN
Karma: 11
Senior Member
I removed both of mine. Both sink and bathroom sink drain through a hepvo valve with no traps.
No smells of any kind.


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: Standpipe Vents [message #347305 is a reply to message #347303] Wed, 04 September 2019 08:56 Go to previous messageGo to next message
Rich Kinas is currently offline  Rich Kinas   United States
Messages: 113
Registered: July 2019
Karma: 1
Senior Member
Wow I have to remember to search for new options for our coaches. The HEPvO seems like a no-brainer. Time to switch. Thanks for the awesome suggestion!
Rich


Rich Kinas 1976 Elaganza II Orlando, FL
Re: Standpipe Vents [message #347307 is a reply to message #347305] Wed, 04 September 2019 09:43 Go to previous messageGo to next message
Richard RV   United States
Messages: 631
Registered: July 2012
Location: Full-timer for 12 years, ...
Karma: -17
Senior Member
I've installed one Hepvo under the kitchen sink so far, two more to go. Great option, picked up some space, no winterizing, little annoying flies no longer using the team as a watering hole. Coachmen had to cut the plywood floor to fit the P-trap under the rear bath tub in the Birchaven. Not a great idea to expose a low hanging water trap to the outside air. 🙄. That's up next.

Richard


'77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemont waiting its turn
Re: Standpipe Vents [message #347314 is a reply to message #347284] Wed, 04 September 2019 10:52 Go to previous messageGo to next message
KB is currently offline  KB   United States
Messages: 1262
Registered: September 2009
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Senior Member
We used an air admittance valve in place of that pipe next to the fridge for the same reason.
It sits just under the sink counter, higher than the drain.

Karen
1975 26'
Re: Standpipe Vents [message #347320 is a reply to message #347284] Wed, 04 September 2019 12:24 Go to previous message
Michael Leipold is currently offline  Michael Leipold   United States
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Registered: April 2011
Location: Greensboro NC
Karma: 2
Senior Member
I plan to install 3 Hepvo Valves (Kitchen, Bath and Shower Drain) and use only 1 standpipe vent.
I just need to find time....


1973 GMC 26' Glacier - Unknown Mileage - Has a new switch pitch transmission with Powerdrive Smile
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