Which vent pipe is the Black Tank?

I was going to suggest inserting a long straw to find out.

Imagine my surprise when I climbed up on the roof of mine and discovered there was only 1 vent pipe. At least I don't have to figure put which one is which. LOL

Ivylog wrote:
If you have not already bought the cyclone I'd put two PVC Ts on. Our coach came with two facing front to rear... No smells and less than $10.

All done. Spent $18.00. NOW you tell me. Oh well, story of my life a dollar short, and a day late. LOL

Thanks anyways. You tried.

If you have not already bought the cyclone I'd put two PVC Ts on. Our coach came with two facing front to rear... No smells and less than $10.

Original Poster here. Thanks for all the suggestions.

When presented with all the options, my wife felt that it would be a lot easier to do the "sniff" test. She went up on the roof, sniffed each pipe. (Remember they are side by side within inches of each other)

One smelled like "shower water" in her estimation. The other smelled like...well, you know what.

So, the if you have the right person, a sniff test will work.

I can just picture this guy, looking into the toilet and saying" Well, hello there. Do you come here often?"
HHAAAHHHHH

4x4van wrote:

ronniedean1234 wrote:
or just talk into your toilet with flush valve open and you can hear which vent the sound comes out of

Just don't do that while IN a campground...you are likely to get some really strange looks from nearby campers!!

It is O.K. I am very used to getting stragnge looks. LOL

ronniedean1234 wrote:
or just talk into your toilet with flush valve open and you can hear which vent the sound comes out of

Just don't do that while IN a campground...you are likely to get some really strange looks from nearby campers!!

John&Joey wrote:

Dog Folks wrote:
I proposed that my DW crawl up there and sniff each one, but that ain't happening!

Just tell the DW to stop being a baby. RV'ing is a team hobby.

LOL. YOU tell her. I'll stand by with the ambulance for you.

put water in toilet, flush and listen in vents for water draining into tank...or just talk into your toilet with flush valve open and you can hear which vent the sound comes out of, no I do not talk to my toilet..lol