|
04-14-2014, 09:59 AM
|
#1
|
1 Rivet Member
1966 22' Safari
Kirkland
, Washington
Join Date: Sep 2012
Posts: 13
|
Does a grey water tank need to be vented?
We're replacing our toilet with a composting one. Our '66 Safari only has the combined black/grey water tank. Since we're removing the black water component, do we still need to vent the tank through the top of the trailer? It will effectively be vented through the drain pipe vents...right?
Also, do we really need to vent the drain pipes? Does the vent do anything other than prevent the gurgling? The only thing connected to the drain is a dish sink. We removed the bath sink and shower. Would a tank full of soapy water really need venting?
If I could remove the vertical piping I could make the interior SO much cleaner!
Thanks,
Karen
|
|
|
04-14-2014, 10:03 AM
|
#2
|
Figment of My Imagination
2012 Interstate Coach
From All Over
, More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,868
|
Any time you let water out of a tank, you have to let air back in at the same time to ensure good flow. That's what the vents do. So the answer is, yes, you still need the vents on the tanks and drain pipes.
__________________
I thought getting old would take longer!
|
|
|
04-14-2014, 11:00 AM
|
#3
|
Rivet Master
1979 23' Safari
1954 29' Liner
Orange
, California
Join Date: Feb 2005
Posts: 3,850
|
Or any time you want to put water into the tank, you must let the air out. That is what the vent does, as it is above the tank inlet.
Bill
Quote:
Originally Posted by Protagonist
Any time you let water out of a tank, you have to let air back in at the same time to ensure good flow. That's what the vents do. So the answer is, yes, you still need the vents on the tanks and drain pipes.
|
__________________
Bill Kerfoot, WBCCI/VAC/CAC/El Camino Real Unit #5223
Just my personal opinion
1973 Dodge W200 PowerWagon, 1977 Lincoln Continental, 2014 Dodge Durango
1979 23' Safari, and 1954 29' Double Door Liner Orange, CA
https://billbethsblog.blogspot.com/
|
|
|
04-14-2014, 11:10 AM
|
#4
|
Rivet Master
2012 25' Flying Cloud
Battle Lake
, Minnesota
Join Date: Jun 2009
Posts: 7,714
|
The storage tanks need to vent pressure and gases.
The drains need vents to prevent not on only gurgling, but siphoning the drain traps enough so dangerous gases from the tanks cannot come back up through the drains. I noticed Airstream uses an air admittance valve near the shower for this purpose in our trailer. You might check on them, if they're legal, and especially proper and safe installation.
__________________
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
The Truth is More Important Than the Facts
|
|
|
04-14-2014, 11:49 AM
|
#5
|
4 Rivet Member
1975 31' Sovereign
Palomar Mountain
, California
Join Date: Feb 2013
Posts: 355
|
Also drains flow much faster with vents. Replaced my bath sink without a built in vent in the sink - when full took what seemed like 5 min.s to empty - went back and added a inline vent beneath the sink and it now flows right out!
|
|
|
04-14-2014, 12:06 PM
|
#6
|
1 Rivet Member
1966 22' Safari
Kirkland
, Washington
Join Date: Sep 2012
Posts: 13
|
Quote:
Originally Posted by Silver Hawk
Also drains flow much faster with vents. Replaced my bath sink without a built in vent in the sink - when full took what seemed like 5 min.s to empty - went back and added a inline vent beneath the sink and it now flows right out!
|
Silver Hawk,
I think you're getting to the heart of my question. What type of vent did you use? Do you still have the big, vertical pipe that goes through the roof?
If I have a vent in the grey tank, and a vent in the sink, wouldn't that do the trick? The only water used in the trailer is in the single sink. The fewer exterior penetrations, the better!
Thanks,
Karen
|
|
|
04-14-2014, 12:54 PM
|
#7
|
Rivet Master
Commercial Member
1957 30' Sovereign of the Road
1959 28' Ambassador
1949 24' Limited
Peru
, New York
Join Date: Sep 2004
Posts: 745
|
Quote:
Originally Posted by kirkland1833
We're replacing our toilet with a composting one. Our '66 Safari only has the combined black/grey water tank. Since we're removing the black water component, do we still need to vent the tank through the top of the trailer? It will effectively be vented through the drain pipe vents...right?
Also, do we really need to vent the drain pipes? Does the vent do anything other than prevent the gurgling? The only thing connected to the drain is a dish sink. We removed the bath sink and shower. Would a tank full of soapy water really need venting?
If I could remove the vertical piping I could make the interior SO much cleaner!
If the tank you are referring to is the original one, it is only a black tank. Grey water in that era went straight to the ground, albeit through the same outlet fitting as the black water did.
Thanks,
Karen
|
Karen,
If the tank you are referring to is the original one, it is only a black tank. Grey water in that era went straight to the ground, albeit through the same outlet fitting as the black water did. Grey water tanks from the factory didn't generally start until 74.
|
|
|
04-14-2014, 01:51 PM
|
#8
|
1 Rivet Member
1966 22' Safari
Kirkland
, Washington
Join Date: Sep 2012
Posts: 13
|
Quote:
Originally Posted by Colin H
Karen,
If the tank you are referring to is the original one, it is only a black tank. Grey water in that era went straight to the ground, albeit through the same outlet fitting as the black water did. Grey water tanks from the factory didn't generally start until 74.
|
Colin,
Yes, it's a black tank. But we had some work done on it and they re-plumbed the sink to dump into the black tank. We're removing the toilet, so the tank will only hold grey water.
I've been poking around and found reference to Air Admittance Valves to vent the drain. If I install one at the sink and have a vent in the tank, that should do the trick, right?
We don't want to have any full height cabinets in our trailer, so I really want to eliminate the ceiling vents. Can the tank vent be routed out the rear of the trailer?
Thanks!
|
|
|
04-14-2014, 02:32 PM
|
#9
|
Rivet Master
Commercial Member
1957 30' Sovereign of the Road
1959 28' Ambassador
1949 24' Limited
Peru
, New York
Join Date: Sep 2004
Posts: 745
|
Quote:
Originally Posted by kirkland1833
Colin,
Yes, it's a black tank. But we had some work done on it and they re-plumbed the sink to dump into the black tank. We're removing the toilet, so the tank will only hold grey water.
I've been poking around and found reference to Air Admittance Valves to vent the drain. If I install one at the sink and have a vent in the tank, that should do the trick, right?
We don't want to have any full height cabinets in our trailer, so I really want to eliminate the ceiling vents. Can the tank vent be routed out the rear of the trailer?
Thanks!
|
Air Admittance allows air in to the drain plumbing to allow water to flow better, but they to not let air/fumes out of the tank…………which is what you need. The top of the tank must be vented outside somehow, either through the roof, or perhaps a vent through the side of the trailer, above the tank. Remember, methane is lighter than air, so it rises.
Colin
|
|
|
04-14-2014, 03:16 PM
|
#10
|
1 Rivet Member
1966 22' Safari
Kirkland
, Washington
Join Date: Sep 2012
Posts: 13
|
Thanks, everyone! I feel like I have a plan now. I will install an AAV along with the sink, and I'll vent the tank through the rear of the trailer.
I really appreciate all of the input!
Karen
|
|
|
04-14-2014, 05:40 PM
|
#11
|
Rivet Master
2012 25' Flying Cloud
Battle Lake
, Minnesota
Join Date: Jun 2009
Posts: 7,714
|
Also, if the sink is near the storage tank and the drain line is large enough you may not need to ventilate with a vent pipe or air admittance valve. There isn't enough water coming from the sink and into the drain line to siphon out the trap. Our bath sink is maybe four feet from the tank and has no sink vent.
There are state plumbing codes for length and size of pipe for this type venting, and rv's probably have their own code if you wanted to research it.
But the tank still needs its own vent pipe (not an air admittance valve).
__________________
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
The Truth is More Important Than the Facts
|
|
|
07-08-2017, 06:34 PM
|
#12
|
2 Rivet Member
Gatineau
, Quebec
Join Date: Jan 2017
Posts: 37
|
two grey tanks
This tread is old but I can't seem to find an answer to my questions in previous treads. To all you plumbing expert out there, here are a few question that this neophyte cannot find answer:
1) If I install two grey tanks that are contiguous and at same level, how do I install a link between the two. What size of fittings and do I need a slope between pipes. I intend to have drains connect under the belly pan.
2) The shower pan would be directly on top of one of he grey tanks. Can it be fitted directly without a p trap? Or do I need to raise my floor?
3) Can the two grey tanks share the same vent? Meaning, can my second grey tank would not have a vent pipe but by being connected to the first grey tank, which would have a vent, it would be sufficient.
Apologies if these questions are silly... The learning curve is steep... :-)
|
|
|
07-08-2017, 06:52 PM
|
#13
|
Half a Rivet Short
2017 30' Classic
2022 Interstate 24X
Carlisle
, Pennsylvania
Join Date: May 2017
Posts: 15,736
|
Quote:
Originally Posted by Juliec
This tread is old but I can't seem to find an answer to my questions in previous treads. To all you plumbing expert out there, here are a few question that this neophyte cannot find answer:
1) If I install two grey tanks that are contiguous and at same level, how do I install a link between the two. What size of fittings and do I need a slope between pipes. I intend to have drains connect under the belly pan.
2) The shower pan would be directly on top of one of he grey tanks. Can it be fitted directly without a p trap? Or do I need to raise my floor?
3) Can the two grey tanks share the same vent? Meaning, can my second grey tank would not have a vent pipe but by being connected to the first grey tank, which would have a vent, it would be sufficient.
Apologies if these questions are silly... The learning curve is steep... :-)
|
Hi
Might be better to start a new thread ....
1) Multiple sewer tanks are not a real good idea. When hooking them "bigger is better". 3" is not a bad starting point.
2) If you run straight into the tank, it will "burp" back into the shower. That's generally not a nice thing. Even the gray tank gets a bit stinky after a while.
3) You can connect both tanks to the same vent. Simply remember that the vent must be at the high point in each tank. Usually this is done with a pipe from each tank going into a Tee and then into the vent.
Yes, there are a few other things to watch out for (setting up the drains ...).
Bob
|
|
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|