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Plunbing Question, to trap or not to trap?

PostPosted: Wed Sep 29, 2010 9:27 pm
by dh
Is a P trap necessary between the sink drain and the grey water tank?

PostPosted: Wed Sep 29, 2010 9:48 pm
by madjack
...the reason for a P trap is to "trap" sewer gases(methane) and other odors and prevent them from entering your dwelling...with that in mind, you should be able to answer your own question................
madjack 8)

p.s in many parks/campgrounds, if you have a plumbing system(sinks/water system) built into your camper, require you to have a grey water catch system...even if you don't(wash dishes inna pot on a table) you are supposed to properly dispose of the water...of course, if you are on BLM, Forest Service or COA type lands boonie camping, these regulations either don't apply or are unenforceable............mj

PostPosted: Thu Sep 30, 2010 6:04 am
by Shadow Catcher
I will second madjack! You do need a gray water tank in many parks campgrounds etc. You need not only a P trap, but you also need a vent for the tank, search holding tank vent.

The prospect of mucking out a tank to find a wedding ring or... that dropped down the sink instead of being caught by a P trap :thumbdown:

The only alternative I can think of is if your sink drains directly into some sort of portable holding tank i.e. the ubiquitous blue plastic jug.

PostPosted: Thu Sep 30, 2010 7:11 am
by madjack
Shadow Catcher wrote:I will second madjack! You do need a gray water tank in many parks campgrounds etc. You need not only a P trap, but you also need a vent for the tank, search holding tank vent.

The prospect of mucking out a tank to find a wedding ring or... that dropped down the sink instead of being caught by a P trap :thumbdown:

The only alternative I can think of is if your sink drains directly into some sort of portable holding tank i.e. the ubiquitous blue plastic jug.


...good point about that wedding ring...they sell a Ptrap for campers which connects directly to the sink and has a hose bib fitting on the side for drainage(I think)...................
madjack 8)

PostPosted: Thu Sep 30, 2010 8:40 am
by GPW
MJ, do I need a P-trap on my Bucket ? :lol: Something Nice about keeping it Simple !!!

PostPosted: Thu Sep 30, 2010 10:01 am
by Dale M.
The also have sink strainers, usually with holes small enough to keep rings and things from going through.....

Dale

PostPosted: Sun Oct 03, 2010 5:56 pm
by 48Rob
Is a P trap necessary between the sink drain and the grey water tank?


All depends on just how "grey" the water really is...

If you flush food scraps, milk, and other items that will quickly develop their own distinct flavor...then yes, you probably need a trap.

If you are careful about what you put down the drain, then you can easily get by without one.

If you have more than one drain that empies into the grey tank, consider the resulting stew, and again base your decision on what will actually end up in the tank.

Rob

PostPosted: Sun Oct 03, 2010 6:48 pm
by George Taylor
I put a grey tank in our campoer just for the fact I don't want to be standing in a mud hole. I do have a trap going into the tank. As for the venting, they make a vent that is mostly used in log homes. It has a valve that allows air to be pulled in when the water goes by, but keep water and the gasses from excaping out. I found 2 in a older 21' camper I junked. It has been a while, but I think that I saw them at Lowes.

PostPosted: Mon Oct 04, 2010 3:30 am
by starleen2
GPW wrote:MJ, do I need a P-trap on my Bucket ? :lol: Something Nice about keeping it Simple !!!


Isn't that kinda implied in your statement - just think about it for a momemnt :thinking: - P-trap??? :lol: :lol:

PostPosted: Mon Oct 04, 2010 7:44 am
by Hikerjohnd
starleen2 wrote:
GPW wrote:MJ, do I need a P-trap on my Bucket ? :lol: Something Nice about keeping it Simple !!!


Isn't that kinda implied in your statement - just think about it for a momemnt :thinking: - P-trap??? :lol: :lol:



Oh that's bad... :lol:

PostPosted: Mon Oct 04, 2010 10:45 am
by jimqpublic
I added a permanent grey tank to our folding trailer primarily for lunch stops. In a teardrop I'd probably try to use a portable tank, but set up inside the cabinet.

Reasons for having the tank plumbed-in:
1- You have to carry it somewhere, might as well be able to use it in the carried position.
2- Quick snack/lunch/etc. stops or when you just want to wash your hands don't require setting up your catch can. (Think of stops in a parking lot where it would be exceedingly inappropriate to drain water on the ground).
3- To satisfy rules at some RV parks (Oregon and Florida have laws requiring a tank that can't overflow on the ground). (The cube-shaped Aquatainer can easily be plumbed with an appropriate vent.)

Regarding P-traps. The standard on small RV's is a very handy little device that doesn't take up any room. Here's a kit that includes the trap, hose, and a male hose connector designed to mount on the outside wall. You can mount it straight to the forementioned Aquatainer. http://www.dyersonline.com/camco-flexib ... drain.html

The Reliance Aquatainer is available in 4 and 7 gallon versions. They have a large cap which includes a thread-in faucet, and a small threaded vent cap. Threads in the large cap are (I think) 3/4" FIP, while the Camco connector uses 3/4" hose thread- which is much coarser. You can get a swivel adapter between the two at any hardware store.

Regarding fresh water- I like the TAB trailer's setup where they use a portable container to feed the pump. Saves space vs. a built-in tank plus carrying a container to refill with.

PostPosted: Mon Oct 04, 2010 10:47 am
by S. Heisley
...good point about that wedding ring...they sell a Ptrap for campers which connects directly to the sink and has a hose bib fitting on the side for drainage(I think)...................
madjack
_________________


Madjack is right. It's a little plastic set-up that screws on. You can get it and the related parts at most RV shops for about $13. Then, you can either hook to a gray water tank or pipe it to the outside and screw on a hose that goes into a tank or canister there. I'm using one and am piping mine to the outside to a hose that dumps into one of those screw-cap 5 gal. water jugs or a fancier set-up.

The nice thing about a portable gray water tank is that you don't have to move your whole trailer to dump the gray water. You just wheel the unit or carry it to where you need to go. The professional units usually sit on the ground and slide under the trailer, out of the way.

Hardware Options

PostPosted: Mon Oct 04, 2010 11:13 am
by Engineer Guy
W/o weighing in on P Trap necessity, I'll mention some details:

1. There are Traps I've used that have a neato, reliable, sealed fitting in the bottom. It's about the size of a Quarter, and turns to one side to open the Trap. This allows 'stuff' in the Trap to be drained into a waiting Bucket. This bypasses the need to use a Plunger or Snake.

2. The item George Taylor refers to is often called an 'Island Trap'. It sits invisibly just under the Countertop of an Island. The 'vacuum' of water going down the drain pulls a lightly-springed Valve open so that replacement air can enter the system, rather than through a Roof-mounted Air Vent.

Re: Hardware Options

PostPosted: Mon Oct 04, 2010 12:17 pm
by fromeo
Engineer Guy wrote:2. The item George Taylor refers to is often called an 'Island Trap'. It sits invisibly just under the Countertop of an Island. The 'vacuum' of water going down the drain pulls a lightly-springed Valve open so that replacement air can enter the system, rather than through a Roof-mounted Air Vent.



Also known as an "air admittance valve." Here's a recent pic from my build thread. Look hard in the upper right hand corner and you can see it in use:

Image

- Frank

Re: Hardware Options

PostPosted: Mon Oct 04, 2010 9:12 pm
by George Taylor
Engineer Guy wrote:W/o weighing in on P Trap necessity, I'll mention some details:

2. The item George Taylor refers to is often called an 'Island Trap'. It sits invisibly just under the Countertop of an Island. The 'vacuum' of water going down the drain pulls a lightly-springed Valve open so that replacement air can enter the system, rather than through a Roof-mounted Air Vent.


Thanks for the corect lingo. I am an electrician not a plumber.