Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-16-2008, 01:05 AM   #1
4 Rivet Member
 
Distantdrummer's Avatar
 
1975 31' Sovereign
Houston , Texas
Join Date: Nov 2003
Posts: 494
Question Rain Water Down Vent Pipes Goes Where ?

Ok we all know about the need for Vent Gaskets to keep water from entering around the outside of the vent pipe where it comes thru the roof.

But what about rain going down the inside of the vent pipe?
I guess it finds its way to the black or grey tanks right?
In a long stored trailer it would eventually fill the tank system and would rise and expel out the lowest openings. Toilet, tub, lav, kitch sink ...?
It would of course never rise back up to the roof thru the vent but would flood the interior of trailer eventually.

Now this is assuming the drain valve from the tanks is closed.

But I have never heard of this happening. Obviously I am overlooking something here.
Oh I realize that it would take alot of rain and that some of the water might evaporate over time (or would it?). But Airstream vent pipes do not have the little awning tops, they are just open to the weather.

Just curious and do not ever remember this being mentioned before.

thanks
__________________

__________________
__________________________
____ d'drummer ____

...aahh..rumm..pu..tum..tummm...
Distantdrummer is offline   Reply With Quote
Old 08-16-2008, 01:13 AM   #2
Rivet Master
Commercial Member
 
lewster's Avatar
 
Vintage Kin Owner
Naples, FL , Hood River, OR
Join Date: Dec 2005
Posts: 7,282
Quote:
Originally Posted by Distantdrummer View Post
Ok we all know about the need for Vent Gaskets to keep water from entering around the outside of the vent pipe where it comes thru the roof.

But what about rain going down the inside of the vent pipe?
I guess it finds its way to the black or grey tanks right?
In a long stored trailer it would eventually fill the tank system and would rise and expel out the lowest openings. Toilet, tub, lav, kitch sink ...?
It would of course never rise back up to the roof thru the vent but would flood the interior of trailer eventually.

Now this is assuming the drain valve from the tanks is closed.

But I have never heard of this happening. Obviously I am overlooking something here.
Oh I realize that it would take alot of rain and that some of the water might evaporate over time (or would it?). But Airstream vent pipes do not have the little awning tops, they are just open to the weather.

Just curious and do not ever remember this being mentioned before.

thanks
DD,

The vents that protrude thru the roof on an RV come directly from the tanks that they are venting, whether black or grey. The rain finding it's way into the vents drains directly into these tanks. Given the capacities of the tanks, I have NEVER heard of any tanks spilling over inside the RV from heavy rain entering thru the vent.

25 gallons of tank capacity would take 40 days and 40 nights of rain to even approach filling, and that's assuming that those little raindrops have one hell-of-an aim right for the vent stack!
__________________

__________________
Lew Farber...ABYC Certified Master Marine Electrician...RVIA Certified Master Tech ...AM Solar Authorized Installation Center...AIRSTREAM Solar & Electrical Specialist...Micro Air 'Easy Start' Sales and Installations
lewster is offline   Reply With Quote
Old 08-16-2008, 01:33 AM   #3
tpi
Rivet Master
 
2005 25' Safari
Trabuco Canyon , California
Join Date: Apr 2006
Posts: 866
Images: 2
Many areas of the country receive 40 inches of rain per year. If the vent pipe was closed at the bottom it would fill to 40 inch level (assuming the opening is the same as the pipe diameter). But when it hits the vastly larger tank area, that 40 inches will disperse to a much lower level, probably less than an inch. Mathematically it could be calculated given the area of the pipe opening and the area of the tank.
__________________
tpi is offline   Reply With Quote
Old 08-16-2008, 04:53 AM   #4
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
rain water

Water that gets into the gray and/or black tanks, regardless of the source, also slowly evaporates.

If you don't believe that, just store a trailer for a period of time, that has sewage in the black tank.

Slowly, but surely, the water evaporates, leaving the black tank dry, and with solid sewage instead of liquid.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 08-16-2008, 09:49 AM   #5
Rivet Master
 
1975 29' Ambassador
Reno , Nevada
Join Date: May 2003
Posts: 1,351
Figure a 2" diameter vent pipe - that's about 3 sq inches cross section. That means 10" rainfall will get you about a pint into the tank. A 40 gal tank is 320 pints so that means you'd need 3200" rainfall to fill the tank through the ventpipe.

During the time you are getting that rainfall, the liquid in the tank is evaporating and the uneven humidity will disperse moisture out of the tank as Andy notes. That's a rather slow process but the length of time to get 3200" rain is probably longer.

My gray tank is only 15 gallons or about a third of 40 so it'd need only a thousand inches of rain to fill it.

Do check the arithmetic based ion "There are 231 cubic inches in one US gallon. Since a cubic foot is 12 by 12 by 12 inches, a cubic foot has 1728 cubic inches. Thus one cubic foot = 1728 cubic inches = (1728/231) gallons = 7.48 gallons." Cubic feet and gallons - 9240 cu in in 40 gal divided by 3 per inch of rainfall is 3k in - cross check ok.
__________________
bryanl is offline   Reply With Quote
Old 08-16-2008, 09:59 AM   #6
4 Rivet Member
 
Darol Ingalls's Avatar
 
Join Date: Mar 2004
Posts: 411
Drummer, Surely you have other things to worry about! Darol
__________________
Darol Ingalls is offline   Reply With Quote
Old 08-16-2008, 10:24 AM   #7
Rivet Master
 
clancy_boy's Avatar
 
2003 22' International CCD
Kiln , Mississippi
Join Date: Dec 2005
Posts: 2,780
Images: 8
Another question answered here on AirForums........

Hummmm, tough to stump you guys.

OK - what is the rate of evaporation of a quart of rainwater in a 40 gal holding tank with a 1800 square inch surface area, out a 2 inch 11 foot long PVC black pipe vent at 85 degrees F and 65% humidity in south MS if the orientation of the trailer is N-NW and the sun is shining and there is a 5mph wind across the pipe opening that the mockingbird lands on 3 times daily looking for crickets in the yard below - thus blocking the vent for a total of 18.745 minutes per day...........

I'll be waiting for the correct answer........


__________________
Michael & Tina with Layla and Preston BZ
The family has grown.
2003 22' INTERNATIONAL CCD
clancy_boy is offline   Reply With Quote
Old 08-16-2008, 10:35 AM   #8
Site Team
 
azflycaster's Avatar
 
1975 25' Tradewind
Dewey , Arizona
Join Date: Mar 2005
Posts: 12,127
Images: 62
Blog Entries: 1
Quote:
Originally Posted by clancy_boy View Post
Another question answered here on AirForums........

Hummmm, tough to stump you guys.

OK - what is the rate of evaporation of a quart of rainwater in a 40 gal holding tank with a 1800 square inch surface area, out a 2 inch 11 foot long PVC black pipe vent at 85 degrees F and 65% humidity in south MS if the orientation of the trailer is N-NW and the sun is shining and there is a 5mph wind across the pipe opening that the mockingbird lands on 3 times daily looking for crickets in the yard below - thus blocking the vent for a total of 18.745 minutes per day...........

I'll be waiting for the correct answer........


Not much.
__________________

Richard

Wally Byam Airstream Club 7513
azflycaster is offline   Reply With Quote
Old 08-16-2008, 10:43 AM   #9
Rivet Master
 
easyride's Avatar
 
1977 27' Overlander
1973 27' Overlander
1963 19' Globetrotter
Naples , Florida
Join Date: Nov 2007
Posts: 1,259
Images: 1
.653428567 quarts per day.that`s assuming the mocking bird is full grown and is only blocking 75% of the vent opening,further information is needed for exact calculations you`re welcome to dispute it,just show me the formula you used.LOL Dave
__________________
easyride is offline   Reply With Quote
Old 08-16-2008, 10:48 AM   #10
Rivet Master
 
richinny's Avatar
 
2011 34' Classic
Westchester Cty.NY , / Miami FL
Join Date: Jul 2007
Posts: 3,122
The Answer to Life, the Universe, and Everything is numeric in Douglas Adams' series The Hitchhiker's Guide to the Galaxy. In the story, a "simple answer" to The Ultimate Question is requested from the computer Deep Thought, specially built for this purpose. It takes Deep Thought 7˝ million years to compute and check the answer, which turns out to be 42.

en.wikipedia.org
__________________
Ricky
2012 F150 Super Crew 5-1/2' bed Ecoboost 4x4 3.73 elec. lock diff. Propride hitch
give life. kidney & pancreas transplant 9/9/06
Ingrid-my unofficial '"World's Oldest Streamer" 1909-2008 R.I.P.
richinny is offline   Reply With Quote
Old 08-16-2008, 11:08 AM   #11
4 Rivet Member
 
Distantdrummer's Avatar
 
1975 31' Sovereign
Houston , Texas
Join Date: Nov 2003
Posts: 494
Arrow

Quote:
Originally Posted by Darol Ingalls View Post
Drummer, Surely you have other things to worry about! Darol
worry..? nope ..?
whats me worry ?

Unappoligetically Curious ..? OH yeah !

My trailers have always been either stored (outside) or parked in the woods (hunt lease) or doing the Driveway-Queen reign.
Actually I have worried (a little) over the years about leaves and roaches and dirt daubers and whatever getting in the vents . Washed down with rain. I even suppose mice could travel there, but unless they could come back out, they would not pose much of a problem I guess. If they could come and go they might bring all sorts of nest building stuff in, which could be bad. I know of no birds that would enter and go down to such a "lovely nesting area".
I guess if it became a One-Way street of no return for mice it might pose a prob if you ended up with 25 gallons of rodent carcasses in their Temple of Doom.

Inland Andy and the Forum math club above have convinced me that the full vent flood is not likely to happen due to Mother Nature.
However we should be careful not to ever park under a gutter drain or any place that a stream might directed into the vent pipe.
Also if you live next to Dennis the Menace or if you go up there and decide to flush out the vent with the water hose, be sure not to go in the house for lunch, nap & nooner and forget to turn off the spigot.

Oh and life and the internet have convinced me that no serious or semi serious question goes long without the class clowns, grafitti gangs or thread hijackers spinning their webs. Course it could be much worse, the "thought police" could get involved. Not that I am worring about that either. < G >
__________________
__________________________
____ d'drummer ____

...aahh..rumm..pu..tum..tummm...
Distantdrummer is offline   Reply With Quote
Old 08-16-2008, 11:15 AM   #12
Site Team
 
azflycaster's Avatar
 
1975 25' Tradewind
Dewey , Arizona
Join Date: Mar 2005
Posts: 12,127
Images: 62
Blog Entries: 1
Part of the gasket kit for the drain is a screen (fine) that will prevent all but the smallest bugs from entering the system. The gaskets should be replace every 5 years. If (when) the gasket fails, the rainwater that lands next to the pipe will enter the shell of the trailer. This is something to be concerned about.
__________________

__________________

Richard

Wally Byam Airstream Club 7513
azflycaster is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Rain Water Leaks MikeSmith Member Introductions 5 07-17-2007 12:10 AM
Insulate those hot water pipes. LTD30 Fresh Water Systems 2 06-09-2006 04:23 PM
Little dribbles of rain water reynolds431 Furnaces, Heaters, Fireplaces & Air Conditioning 11 10-16-2005 12:57 PM
replace old copper water lines with plastic pipes m. Clarke All Argosy Trailers 7 03-27-2004 12:42 AM
Where do these water pipes go? letsgo Fresh Water Systems 1 12-21-2003 08:56 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 11:19 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.