| Author |
Message |
MC - Iv
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, March 04, 2005 - 12:51 am: | |
I am starting to design my plumbing system and have the tanks for black and grey.The grey tank will be above the black.
Can I use one hole for the tank as an inlet and a vent,(like a "wet vent" in residential) or should I install a separate hole for the vent in each tank.
Also, I was planning to install a secondary drain from the grey to go into the black using a sanitary tee on the black vent.
I hope this doesn't sound too confusing. I just have to know how many "spin on" fitting to allow for.
Thanks, Iv.
P.S. I found some interesting flexible neoprene elbows and tees at H.D. which will really simplify installation of the drain system in hard to reach areas. |
CoryDaneRTS
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, March 04, 2005 - 1:54 am: | |
(" Can I use one hole for the tank as an inlet and a vent ")
<<<>>>
The norm is to have a separate vent in the tank. This is to prevent presurizing the tank and possibley damaging the tank seams.
On the other hand, with a pipe large enough to handle a down flow as well as up flow, you may be ok. It seems that there would be some resistance since both drain and vent are utilizing the same space, but as long as you do not supply enough drainage to fill the "2 way" drain/vent pipe, the operation should go flawlessly.
(" to install a secondary drain from the grey to go into the black using a sanitary tee on the black vent. ")
<<<>>>
This is used by some to extend the use of the grey water. When the grey tank gets too full it can overflow, thus allowing some additional time.
SOME can bypass the grey tank and either go direct to dump or to the black tank.
There are many variations to use.
cd |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, March 04, 2005 - 8:28 pm: | |
MC,
ANSI/NFPA 1192 permits "wet vent" systems in RV's subject to certain constraints on pipe sizes.
I highly recommend you purchase or borrow a copy of this publication and read it thoroughly. Last I checked, it was available on-line for less than $50.
My gray water system is wet vented with no problems.
-Sean |
Sean Welsh (Sean)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, March 04, 2005 - 8:34 pm: | |
Addendum...
I should have been clear that wet-venting is for waste only and not soil.
Also, your proposal to connect gray and black tanks is prohibited upstream of the dump valves (known in the trade as "fullway termination valves").
If you want to combine tank capacities, you should use combined black/gray tank(s), which makes all your DWV system "soil" and imposes additional restrictions on how things are plumbed. Again, get the book -- it's invaluable.
-Sean |
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