grey water tank problems

my grey water tankk in the trailer seems to alway's get air locked makes it awfull hard to do the clean up work. it has a vent in it that seems to be okay?? my setup goes from the wash-rinse,-sanitize ,then pipe goes and hooks into hand wash thats where the vent pipe is it att. to the "p"trap by the hand wash sink. any body had these kind of problems?

I don't see how tank would air-lock if it has a proper working vent.    ... the problem must be with the drain piping.   ... Can you give more detail?

RU sure theirs not greese cloging the line????

it will drain fine for awhile then it will stop up and when it does go down it will spirt water back up the hand wash sink, then drain out. i've taken all the drain pipes apart and checked for blockage everything is clear. i'm thinking maybe the vent pipe is clogged it looks like theres a threaded piece at the top of the vent but it dont seem to want to come apart with out breaking something.

your tank will get sludge in it it will build up in the pipes. Not sure what size your drain pipes are, but I had to upgrade mine to 3/4 to properly drain them. I would get onions stuck in mine, causing my overflow pipe to build up and spew everywhere.  went thru that about 10 times before I upgraded.  any pics of your plumbing will be helpful

my drain pipes are regular houshold size 1 1/4 OR  1 1/2 I believe. I'm going to look at that vent again and see if it might be plugged up .

The general rule regarding venting of water lines is Air BEHIND Water. It sounds like you have your vent in the middle? Sinks, vent, tank. If this is the setup, I can see why you are having problems. You need to move the vent to the begining of the process, at your first sink so that the air pushes the water to the tank, if that makes sense.
 
Mike

You say the water backs up into the sink ? Do you not have it built in with an air-lock ? There should be an open space between the end of the pipe which allows the water to free flow into a hopper drain. I think you might have a manifold drain system in which there is no break in the pipes.  If this is the case, ( not getting on your case ) I don't know how the HD approved that. They have big issues in MY area to make sure NO water backs up into any of the sinks for contamination purposes. Is there anyway you can possibly post a picture of your sink setups ?
 
You def don't want water backing up into your sinks. My p-trap is built onto my hopper drain which is directly connected to my waste tank. Everything else is straight piped to flow into the hopper drain.

We plumbed ours like this block diagram shows (link follows). It's a pretty basic holding tank system. You sound like you have yours plumbed like for a "house" set up (wet vent plumbed into the drain limes). For a holding tank you need to allow the displaced air to  purge from the holding tank as water enters the tank. Otherwise it will "burp" or back fill because if the air trying to get out.
 
http://www.marxrv.com/plumbing/plumb.htm
 

okay gottit ! just as i thought the air vent stack was operating improperly, actually backwards, got it fixed and works fine now. thanks for all the replies to help! Buck 

Hi Buck.
 
Sorry I am late to post. Was the problem a "scooter vent" installed to vent the tank? I saw that done once and was going to mention, they only vent in one direction so it won't work on a tank.
 

 

JohnL
...Was the problem a "scooter vent" installed to vent the tank?

That is called a "check" vent or a "cheater" vent.

that is exactly what it was. i cant see how they expect this to work ??it allows air to go in but not to come out. seems as if it worked backwards to what it needed?

You need to remove it and replace with an open goose-neck with piece of screen to prevent bugs from getting into the tank.
... As it was, ...  there was not way for the tank to vent it's self but thru the sink drains. Back pressure cause the water to bubble in the sinks.
 
Oh ... you might want to make sure the vent is higher/taller than the top of the sinks.   This will prevent overflowing the tank, if you forget to empty it.

nope.!! thought i had it but it's still blocking up at times #@*#@ thing

I just had to drain a 21 gallon waste tank, that was clogged. Had it slip out of my hands and emptied all over my trailer floor. You talk about SUCK. It smelled so bad, I thought I was going to puke out of the top of my head.
 
I had to drill my tank and put in a very large drain pipe 1 3/4. Still don't have the tank hooked back up 100%. Waiting on the epoxy to cure.
 
Ive asked before. Is there anyway that you can take a picture of your plumbing set up ?  Is the tank not draining ? is it backing up still ? What are your drain pipes look like ? Are they big enough to where food isn't getting in the way and clogging them up ?  My problem was a pellet of something that resembled blue cheese, got stuck in my line. ( hence my drainage wasn't big enough.)