Installing the 360 Siphon RV Fume Extractor

Nasty Smells in the RV

Sometimes after towing our trailer I will notice during setup at the campsite the smell of waste tank odors. I think what happens is with all the rocking and rolling the trailer endures while on the road, the water in the plumbing P-traps gets washed away and tank odors can seep inside the rig. I believe a simple upgrade to the standard RV roof top waste tank vent covers will be a solution to these nasty odors. A product called a 360 Siphon looks to be just the ticket.

360 Siphon RV vent

360 Siphon RV Rooftop Waste Tank Vent Cover

I’ve seen some rigs with a spinning fan sort of waste tank fume extractor but really like the fact that the 360 Siphon has no moving parts and sits nice and flat with a dome top. Even when very careful driving in treed areas an occasional brush with branches is not uncommon for us.

With its low profile, alien space ship looking design it creates an air vortex that sucks the fumes up and out of the waste tank. Anytime air is moving through it suction is created drawing the fumes out of the waste tank. They say this actually reduces or even eliminates the need for tank odor control chemicals. I like that, as I hate using any chemicals in the waste tanks.

360 Siphon beside regular vent

Installing the 360 Siphon RV Fume Extractor

The installation of the 360 Siphon is very simple, takes maybe 20-30 minutes and needs very few tools, but does mean a trip up onto the RV roof and time on a ladder. I’m very used to climbing up on our rigs roof and thankfully quite agile. If you aren’t its best to have an RV service department do the job.

The first thing that needs to be done is remove the existing waste tank vent cover. Normally they are held in place by multiple screws and sealed with caulking. Try to do the job on a warm day so the caulking is soft and easier to remove. Our rubber type roof is caulked with a product called Dicor self-leveling lap sealant. This stuff stays kind of soft and is pretty easy to remove like a big glob of bubble gum. I like to use a dulled metal scraper, pry bar type tool. Some folks like to use a plastic one just in case of slipping and damaging the roof.

Once I got my old vent off it quickly became apparent the vent pipe was far too high above the roof plane to fit the 360 Siphon. I needed to cut it down to around 5/8ths of an inch above the roof. This was easily done using a hack saw blade.

After cutting the pipe to the proper height and cleaning up the surface I added some Dicor sealant to a gap between the pipe and the rubber roof then added the supplied butyl tape to the mating surface of the 360 Siphon.

The 360 Siphon comes with a small plastic adapter piece so you can use it with 1 ½ inch or 2-inch pipes. That gets inserted into the vent pipe and the main body is screwed down over that. Finally, I gave the outside edge and screw heads a good coating of the lap sealant. That’s it!  A nice little inexpensive upgrade to my Keystone Cougars waste ventilation system.

360 Siphon RV vent installed

360 Siphon RV vent installed

Video Detailing the 360 Siphon Vent Installation

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