Jump to content


Photo

Gray tank vent


  • Please log in to reply
41 replies to this topic

#16 Larry & Debbie Gamble

Larry & Debbie Gamble
  • After-Market Product Supplier
  • 669 posts
  • Local time: 10:38 PM
  • Location:Under a Casita most of the time
  • Casita Model/Size:96 17SD
  • Gender:Male

Posted 09 April 2009 - 07:07 PM

Campnagle,
Don's reference to the part number is correct. 89-8151, and the proper size is 1 1/2". That's actually a Stag-Parkway (distrubutor) part# but that would be the number to use regardless of who you order it from. During the initial testing of this mod, I hooked the valve backwards up to a pressure system for 24 hours at 20 PSI. I'm no engineer, but that was a number I pulled out of thin air as 40% more than atmospheric pressure. The goal was to see if sewer gas (under slight pressure) would flow backwards thru the valve. It held the pressure. I've had mine in for nearly a year and had it out 3 or 4 times looking for problems and found none. Small shower debris here and there but nothing seems to clog it. I also flushed a hand full of grass clippings down the shower during testing. Like something you might track into the shower during a normal day. No clogs. I drove 3000 miles with a half full gray tank and took it to 13000 feet with no falures and a dry shower floor. I know of about 25 Casitas that have this mod and the only reported failure was from a rock. I'm not sure it's bullet proof, and a year isn't very long, but no news is good news! biggrin.gif

Don,
Nice touch on the vent mod going into the closet and tying in above the sink drain!. No possiblility of it accidentally becoming a "wet" vent!


Larry
Larry & Debbie Gamble
Original owners 96 17 SD
The Honeymoon Cottage


www.LittleHouseCustoms.com

#17 Larry & Debbie Gamble

Larry & Debbie Gamble
  • After-Market Product Supplier
  • 669 posts
  • Local time: 10:38 PM
  • Location:Under a Casita most of the time
  • Casita Model/Size:96 17SD
  • Gender:Male

Posted 09 April 2009 - 07:26 PM

Keith,
Good question! While it does increase the capacity and (for some) slightly improve the flow and only takes 5 dollars worth of parts, Casita probably wouldn't sell more trailers if they did it. In fairness, they don't mislead anyone. They do downgrade their representation of the tank capacity to 25 gallons and most folks can get 25 in without the mod. And then of course, we'd all have to find something else to do when we're not camping. biggrin.gif For what it's worth the Hepvo mod also slightly increases capacity but only as it relates to using the two sinks. When the tank is full, the shower will not drain as usual. However more water can be added to the sinks utilizing the vertical portion of the plumbing above the tank all the way up to the top of the sink rims. That sink water will NOT come up in the shower floor. So bacon grease on the shower floor is history!

Larry
Larry & Debbie Gamble
Original owners 96 17 SD
The Honeymoon Cottage


www.LittleHouseCustoms.com

#18 KandJ

KandJ
  • Casita Club Member
  • 506 posts
  • Local time: 09:38 PM
  • Location:Front Range Colorado
  • Casita Model/Size:17' FD
  • Gender:Male
  • Trailer Name:Humpty Dumpty

Posted 10 April 2009 - 05:58 AM

QUOTE (Larry & Debbie Gamble @ Apr 9 2009, 08:26 PM) <{POST_SNAPBACK}>
Keith,
Good question! While it does increase the capacity and (for some) slightly improve the flow and only takes 5 dollars worth of parts, Casita probably wouldn't sell more trailers if they did it.

Larry


Larry,

My reason to do this would be to increase the water flow during a dump, not the increase in capacity. On mine, 2006 17' FD the dump time is substantial and any reduction of time might be worth the mod. You say it only slightly increases the flow? One post says that it went from 12 min to 4 min. Was that unusual or would someone might expect a longer time?

I think I may try this.

Thanks!

Keith

2006 17' FD
2003 Ranger 4X4 Ext Cab 4 liter

Our Travels

 

AVE IMPERATOR MORITVRI TE SALVTANT


#19 Larry & Debbie Gamble

Larry & Debbie Gamble
  • After-Market Product Supplier
  • 669 posts
  • Local time: 10:38 PM
  • Location:Under a Casita most of the time
  • Casita Model/Size:96 17SD
  • Gender:Male

Posted 10 April 2009 - 04:24 PM

Keith,
Well, we've kind of hijacked a thread, but not totally as all these drainage issues are related. In Don's post with his links to his photos, he has actually detailed three separate but related mods.

The vent mod as Campnagle did (first post in this thread) is the mod that increases capacity. While some report a decrease in drain time, my experience with the many that I have done is to the contrary. No significant improvement. Too many other restrictions in the system.

The "valvectomy" as I call it replaces the shower valve and the shower trap with a Hepvo waterless trap. This slightly increases capacity, has other benefits but is unrelated to increasing draining speed.

Don's significant drain speed improvement was accomplished using a new mod recently developed on the Casita Forum that replaces much of the gray drainage system and REQUIRES the vent mod be done as well. So doing the vent mod is at the least the first step in a speed improvement. While I'm sure he's pleased, I'm dissapointed in his results as about 10 Casitas have now done this "Fast Gray" mod and ALL are draining in about 2 minutes 20 seconds except for his. I intend to check his out (assuming I'm welcome) at Bluebonnet and see if I can figure out why his is so slow at 4 minutes. Most unmodded (is that a word?) Casitas drain in 7 to 10 minutes.

Since I see you're on the attendee list for Bluebonnet, I'll mention that I will be doing several demos of all three mods both before and during the rally. I am also on the agenda to give a presentation after the swap meet Saturday afternoon. All three mods will be discussed at length during the class as Brad has allowed over 2 hours for it.

The vent mod itself is quite old an has been discussed for years on both forums. The other two are fairly new and here's links to lengthy discussions of both.

http://www.casitafor...?showtopic=4444 "Fast Gray Mod"

http://www.casitafor...?showtopic=3493 "Valvectomy Mod"


Hope this answers your questions. Or at least clears some of them up.

Larry
Larry & Debbie Gamble
Original owners 96 17 SD
The Honeymoon Cottage


www.LittleHouseCustoms.com

#20 rvonroad

rvonroad
  • Casita Club Member
  • 9 posts
  • Local time: 07:38 PM
  • Location:Spring Branch, TX
  • Gender:Male

Posted 16 April 2009 - 10:33 AM

I went to Lowes, Home Depot and a local hardware store looking for the 1/4" to 1/2 barb fitting but had no luck. I was looking for it on the internet when I found a 1/2" Stem to 1/2" Tube Hose Barb at heatsinkffactory.com. Got a couple, drilled 1/2" holes, applied some SuperGlue, and let it set overnight. Now I don't have 1/4" tap that I would never use again.
COD
(C.O. Shaw, WC5S -- Dolores Spencer, KD5PDS)
09 17'FD
Spring Branch, TX

#21 GRIZZLYJERRY

GRIZZLYJERRY
  • Casita Club Member
  • 56 posts
  • Local time: 07:38 PM
  • Location:FT WORTH, TEXAS
  • Interests:ATV RIDING(Polaris RZR)
    METAL DETECTING(BEACH)
    RECUMBENT BIKE(BACHETTA AERO)
  • Gender:Male
  • Casita Club Directory #:9274

Posted 16 April 2009 - 12:10 PM

Ace Hardware has the fitting. Plastic 1/2 pipe thread by 1/2 barb with 1/4 hole. There's no pressure to deal with so i drill the hole out to 3/8. Bigger is better.

#22 Larry & Debbie Gamble

Larry & Debbie Gamble
  • After-Market Product Supplier
  • 669 posts
  • Local time: 10:38 PM
  • Location:Under a Casita most of the time
  • Casita Model/Size:96 17SD
  • Gender:Male

Posted 17 April 2009 - 05:44 AM

Lots of folks have glued theirs in with no reports of failure. Plenty of places would loan or rent the tap as well if that's the approach folks want to take. I met a fella at a rally that told me he drilled his holes then drove to a plumbing shop early one morning with a box of donuts and they tapped them for him. No end to the ways this mod can be done. I've done dozens of them at rallys for folks as well.

Larry
Larry & Debbie Gamble
Original owners 96 17 SD
The Honeymoon Cottage


www.LittleHouseCustoms.com

#23 Chris C

Chris C
  • Casita Club Member
  • 1,046 posts
  • Local time: 10:38 PM
  • Location:Central Oklahoma
  • Interests:Custom Furniture builder. Photography. Paragliding. Camping. Llamas. Really living life! (on and on and on and on!)
  • Gender:Male

Posted 10 June 2009 - 05:25 AM

I know I'm always slow to get some of these modifications done, but I installed my gray water vent yesterday. Of all the modifications I've done to the Casita, it was the easiest and quickest to do. (Except for changing the license plate from a New Mexico one to and Oklahoma one when I bought it!!!!!!) biggrin.gif I ran the vent up through the closet floor to just above the drain from the bathroom sink. I'm preparing for a "dry" 3-day trip and the extra room in the tank will be welcomed.

Chris
2006 17' Spirit Deluxe pulled with a White 2008 Honda Ridgeline RTS.


Visit My Website


#24 Sue and Sandy

Sue and Sandy
  • Casita Club Member
  • 1,703 posts
  • Local time: 09:38 PM
  • Location:Colorado Western Slope
  • Casita Model/Size:2001 16ft. Freedom Deluxe
  • Gender:Couple

Posted 13 June 2009 - 10:13 AM

Keith,
If you want to decrease the dumping of the gray tank, do the gray tank vent mod.
Sandy just finished doing this mod yesterday, and when we tried dumping water from a full tank, it came out much faster than before. We will still prop the Casita on blocks to get the maximum amount out, but it will take less time now.

Thanks to everyone for the pictures, descriptions, discussion and inspiration!

Susan

Edited by Sue and Sandy, 13 June 2009 - 10:16 AM.

post-176-0-54687300-1405271931_thumb.jpg

2001 16' FD "The Alpine Egg-Spress" #1155
2013 Ford F150 Supercab 4X4


#25 KandJ

KandJ
  • Casita Club Member
  • 506 posts
  • Local time: 09:38 PM
  • Location:Front Range Colorado
  • Casita Model/Size:17' FD
  • Gender:Male
  • Trailer Name:Humpty Dumpty

Posted 14 June 2009 - 01:11 PM

QUOTE (Sue and Sandy @ Jun 13 2009, 11:13 AM) <{POST_SNAPBACK}>
Keith,
If you want to decrease the dumping of the gray tank, do the gray tank vent mod.
Sandy just finished doing this mod yesterday, and when we tried dumping water from a full tank, it came out much faster than before. We will still prop the Casita on blocks to get the maximum amount out, but it will take less time now.

Thanks to everyone for the pictures, descriptions, discussion and inspiration!

Susan


Susan,
I had Larry do the mod when we were in Bandera at the Bluebonnet. I just finished taking everything out of Humpty Dumpy and the truck after almost 7,000 miles to the southeast. The mod did work as we had numerous places where we had to dump. It does work and the extra vent mod does increase the gray water. We spent 4 nights dry camping in the Great Smokey Mountains National Park and we each had a good cleanup at night and a full shower each morning and did not fill the tank. I had to add extra water to the tank from the 5 gal jugs. The rest of the time we at least had electricity for the air conditioner. Hot and humid! I ordered the HepVo valve when we were gone and I will put in as soon as I get to it.

Thanks Larry!

Keith

Got to run, Jane says that there is funnel cloud I need to look at.

2006 17' FD
2003 Ranger 4X4 Ext Cab 4 liter

Our Travels

 

AVE IMPERATOR MORITVRI TE SALVTANT


#26 Larry & Debbie Gamble

Larry & Debbie Gamble
  • After-Market Product Supplier
  • 669 posts
  • Local time: 10:38 PM
  • Location:Under a Casita most of the time
  • Casita Model/Size:96 17SD
  • Gender:Male

Posted 15 June 2009 - 04:29 AM

Keith,
Glad the two mods worked out for you! Capacity and velocity are what it's all about. Sorry we couldn't get to your valvectomy as well, but you'll have fun doing it. Post when you get it done.


Larry
Larry & Debbie Gamble
Original owners 96 17 SD
The Honeymoon Cottage


www.LittleHouseCustoms.com

#27 Paul from NWOnt

Paul from NWOnt
  • Casita Club Member
  • 48 posts
  • Local time: 10:38 PM
  • Location:Fort Frances, ON
  • Casita Club Directory #:2914

Posted 15 June 2009 - 06:46 PM

QUOTE (Larry & Debbie Gamble @ Apr 10 2009, 06:24 PM) <{POST_SNAPBACK}>
Don's significant drain speed improvement was accomplished using a new mod recently developed on the Casita Forum that replaces much of the gray drainage system and REQUIRES the vent mod be done as well. So doing the vent mod is at the least the first step in a speed improvement. While I'm sure he's pleased, I'm dissapointed in his results as about 10 Casitas have now done this "Fast Gray" mod and ALL are draining in about 2 minutes 20 seconds except for his. I intend to check his out (assuming I'm welcome) at Bluebonnet and see if I can figure out why his is so slow at 4 minutes. Most unmodded (is that a word?) Casitas drain in 7 to 10 minutes.


Larry


This may have something to do with the length of his vent line, and the resulting flow restriction (it has to do with hydraulics and pressure). I would try just using a spare chunk of line a few inches long stuck onto the barb in the tank and see if that makes an improvement. The solution, if this works is to either re-route the vent so it's shorter, or use a larger diameter vent line.

Wouldn't you know it, I couldn't find the specific mention of it in my manuals, but it has to do with the length of the pipe (or in this case plastic line), the pressure pushing against it (in this case, atmospheric), and the smoothness of the pipe wall (the plastic is pretty smooth) - All coupled together with the diameter of the pipe to tell you your flow rate at the end of the system. In the case of the elongated vent, there is a good possibility that during the first part of the dump, the system is still acting like a wet vent.

Disclaimer: I never pulled out the calculator, it's just an educated guess if all other things are equal. It's also easy to test in a non-destructive way.


#28 Larry & Debbie Gamble

Larry & Debbie Gamble
  • After-Market Product Supplier
  • 669 posts
  • Local time: 10:38 PM
  • Location:Under a Casita most of the time
  • Casita Model/Size:96 17SD
  • Gender:Male

Posted 16 June 2009 - 04:34 AM

Paul,
I did spend some time looking at Dons's issue and a great deal more time thinking about it. His revent mod which is only a small portion of the Fast Gray mod, is unique in that it passes into the closet and ties into the vent above the inlet from the bath sink. In theory this should be good as it would prevent the revent tube from ever becoming a wet vent. That being said, it's not the way most of us have done it. My only suggestion to Don was to test the system for being undervented by removing the kitchen sink trap to turn that side into a temporary additional vent. He did the test and only noted a few seconds in faster drain time. I noted no difference in his modded system (other than his vent tie in point) and the 11 I've done and 5 done by others that I've had a chance to check out.
I suspect that one variable is a test criteria has never been established. Other than timing the draining while set up level, some might stop the clock when it gets to a slow trickle, and others when it gets to a fast or even a slow drip. This alone could add a minute or more to the drain time. But regardless of the criteria, Done reduced his time (using his own consistent critera) by 7 or 8 minutes! So he's happy. But your suggestion is valid and would certainly be worth considering. I will certainly test the theory on my own Casita.

Thanks,

Larry
Larry & Debbie Gamble
Original owners 96 17 SD
The Honeymoon Cottage


www.LittleHouseCustoms.com

#29 Paul from NWOnt

Paul from NWOnt
  • Casita Club Member
  • 48 posts
  • Local time: 10:38 PM
  • Location:Fort Frances, ON
  • Casita Club Directory #:2914

Posted 16 June 2009 - 06:48 PM

If there was only a few seconds improvement, then the capacity of the vent line must be sufficient.

Interesting dilemma. I agree that a standardized test method would be nice, but as you said; The man's happy with it.

That is perhaps the best result one could ask for. biggrin.gif

#30 Vernon Jessup

Vernon Jessup
  • Casita Club Member
  • 5 posts
  • Local time: 10:38 PM
  • Location:Memphis TN
  • Gender:Male

Posted 15 July 2009 - 11:41 AM

I noticed on the new Casita Web site - under Feature - They list the gray water tank as 32 gal. Are they using this gray water vent system now?