2021 373FB-R Roof Vents

[MichaelJTrent]

So our rig is relatively new (<1 year) and when first hooking up at a site, the first time we flush the toilets we get horrible black tank smell throughout and around our RV.

I decided to replace the black tank vents on the roof with a better quality siphon vent from Lippert so I bought 2. When I got up on the roof I realized I have 4 vents, one for each black and grey tank.

I couldn't find any information about which vent belonged to which tank, so I made a best guess based on where the vents were located and which ones failed the old smell test.

The 2 front vents are in the master bath and the left-most one is over the shower (below in red), which is next to the toilet. The other front vent is located right above the master bath dual vanities.

The 2 rear vents are above the half bath and the left-most vent is above the sink while the middle vent is almost directly above the toilet (below in red).

I was wondering if anyone would have any insight as to which vent is which. It's sort of a moot point now because the vents are installed, but I am curious if I got the right ones.

If you look from the sky downward, this is the layout of my vents and the red X's are the ones I replaced.

[Yoda]

So our rig is relatively new (<1 year) and when first hooking up at a site, the first time we flush the toilets we get horrible black tank smell throughout and around our RV.

I decided to replace the black tank vents on the roof with a better quality siphon vent from Lippert so I bought 2. When I got up on the roof I realized I have 4 vents, one for each black and grey tank.

I couldn't find any information about which vent belonged to which tank, so I made a best guess based on where the vents were located and which ones failed the old smell test.

The 2 front vents are in the master bath and the left-most one is over the shower (below in red), which is next to the toilet. The other front vent is located right above the master bath dual vanities.

The 2 rear vents are above the half bath and the left-most vent is above the sink while the middle vent is almost directly above the toilet (below in red).

I was wondering if anyone would have any insight as to which vent is which. It's sort of a moot point now because the vents are installed, but I am curious if I got the right ones.

If you look from the sky downward, this is the layout of my vents and the red X's are the ones I replaced.

If the vent is white it is most likely a roof /attic vent, Tank vents are black. There may be a screw holding the black/gray vent caps on (or not) but they pull straight up to get off. If there is a pipe down from there it is a tank vent. If you pull the cap of the attic vent you should see insulation - no pipe. If you pull your basement pass through wall you will see how the tanks vents are probably combined/connected.

Hope this helps

[MichaelJTrent]

I appreciate it. All four of the above referenced pipes are black. I'm 100% sure they all go to either the front black\grey and rear black\grey.

I also pulled down the smaller basement wall and used that info to help me decide which of the four vents to replace.

Like I said, it's done now so this is really just me hoping for confirmation I got the right ones. Thanks again!