Community Forums

fortisi876 · 10-30-2014, 12:19 PM

Hello all!

So I just picked up two 360 Siphon vent caps for both tanks. Unfortunately, my MH has what I think is a unique problem as the makers of these vent caps have never seen it either. My OEM caps are vented out of the roof side by side, approximately 3.75"-4" on center. (Photo #1 & 2 below)

#1

#2

The makers of the 360 vent cap thought it'd be best to send me one cap with the flange and the other without since they were so close together. While trying to modify the brand new vent caps as best as I could, although I did manage to get them mounted (staggered in height) I didn't like the fact that the unflanged cap was nearly an inch off the roof and short of drilling into the vent stack to adhere the cap to it, there'd be no other way to secure it to the roof. (Photo #3 below)

#3

My question is, I have access to both of these vent pipes in the laundry cabinet, they are 1.5" ABS pipes. Would it be a problem to combine BOTH vent pipes by adding a PVC wye coupling inside???

#4

THOUGHTS?!?!?

This way I'd eliminate one cap altogether and just need to patch the roof appropriately. I'd like to knock this out tomorrow so any advice would be appreciated!!!

fletch460 · 10-30-2014, 12:24 PM

dammed good idea

BFlinn181 · 10-30-2014, 12:34 PM

I think it's a good solution to the problem. I don't think it will create new problems for your tanks venting through the one cap. The other option would be to use the closet access to move one vent further away from the other and use both caps, but I don't think you'd gain any better venting.

JFXG · 10-30-2014, 08:28 PM

I don 't see any reason not to. Done all the time in residential.

exrench · 10-30-2014, 08:47 PM

What point is there to alter the OEM set-up? The vent is to the outside and the wind carries the odour away. What more is to be accomplished?

BFlinn181 · 10-30-2014, 09:09 PM

Quote:

Originally Posted by exrench

What point is there to alter the OEM set-up? The vent is to the outside and the wind carries the odour away. What more is to be accomplished?

The addition of the 360 Siphon vent cap creates negative pressure so gases don't come back up when flushing the toilet. It's much more efficient than the standard cap.

stink · 10-30-2014, 09:17 PM

Might try trimming one vent cap to fit next to the complete one and glue together with dycor.

fortisi876 · 10-30-2014, 09:20 PM

Quote:

Originally Posted by exrench

What point is there to alter the OEM set-up? The vent is to the outside and the wind carries the odour away. What more is to be accomplished?

Seriously?

I've only been a MH owner for 3 yrs and I've lost count on how many topics I've seen posted on RV forums about black and/or gray tank odors creeping inside the MH.

If you haven't experienced those odors, consider yourself lucky.

HerbZilla · 10-30-2014, 09:23 PM

No reason it shouldn't work. The only reason for two to begin with is to keep the two systems isolated so they don't mix fluids it's a code thing. But if you are backed up to your roof I am pretty sure you would have other concerns than wondering if I am meeting code!!!
Plus if it doesn't work you already have the one hole filled in so you can just relocate a second hole for a second vent. Either way your problem is solved.

fortisi876 · 10-30-2014, 09:25 PM

Quote:

Originally Posted by stink

Might try trimming one vent cap to fit next to the complete one and glue together with dycor.

I actually had one cap marked off to cut up, but then noticed that the top cap has like an airfoil design which I have to imagine is what helps pull the odors out with the lightest breeze, as advertised. I didn't want to risk damaging that design concept so that's when I began to think of eliminating one altogether.

Thanks for all the replies gentlemen, I already picked up a wye and 45* elbow, plan on buttoning it all up tomorrow.

Papa_Jim · 10-31-2014, 06:33 AM

I think modifying this to one pipe exiting through the roof is a very smart idea.

When you look at creations like this, it makes you wonder what was going on to cause the people to create it? Let's see, two different crews, each working on their own tank, one grey, one black. Each crew working their way to running their own vent pipe to the same spot through the roof as the other crew. What this means is one crew missed the mark and ended up putting their pipe beside the other pipe!

Enough Jim.

Jim

ChasA · 10-31-2014, 07:10 AM

Combining the 2 pipes with a sanitary wye wil work just fine. Both of the Winnebagos I've owned had only one vent on the roof. The vent pipes from the 2 tanks were connected inside a wall.

MarkofSJC · 10-31-2014, 12:01 PM

Here's a thought. You currently have a larger hole for two pipes in your roof. Would it not make more sense to use a Y adapter, but have a larger diameter pipe going through the roof? It may increase the volume of air flow (eliminating any bad smells in the coach) and be a tighter fit for the roof penetration (less chance of leakage)

BFlinn181 · 10-31-2014, 12:36 PM

Quote:

Originally Posted by MarkofSJC

Here's a thought. You currently have a larger hole for two pipes in your roof. Would it not make more sense to use a Y adapter, but have a larger diameter pipe going through the roof? It may increase the volume of air flow (eliminating any bad smells in the coach) and be a tighter fit for the roof penetration (less chance of leakage)

Problem with that is the new 360 Siphon vent cap wouldn't fit over a larger diameter pipe. Plus, the larger size isn't really needed for venting and the roof hole can be adequately sealed, small or large.