Camco Cyclone or 360 Siphon holding tank vent covers?

If you have a sink that drains into the black tank then it should have one of these vents downstream of the P-trap. It keeps the water from being sucked out of the P-trap when you dump the black tank. It is also a source of air intake for the roof vent (other than flushing the toilet) to help draw the sewer gases out of the holding tank.

cruz-in wrote:
I too thought that they must pull the air from somewhere. If nothing else when you flush the toilet, theoritically, there is a bit of a negative pressure in the tank that will cause flpw up the vent pipe....but once the toilet valve is closed, not sure where the air to be pulled out comes from...

Having said that, there is a Camco Clyclone on the rig next to us. When the wind blows so that the rear of the cyclone is facing our rig, if you are in line with it, you can smell a faint tank odor. So it must be pulling something.

Keep in mind that the air passing the Cyclone isn't the only air blowing in your face. You are downwind of the entire RV including the sewer connection and anything else in that general area.

I too thought that they must pull the air from somewhere. If nothing else when you flush the toilet, theoritically, there is a bit of a negative pressure in the tank that will cause flpw up the vent pipe....but once the toilet valve is closed, not sure where the air to be pulled out comes from...

Having said that, there is a Camco Clyclone on the rig next to us. When the wind blows so that the rear of the cyclone is facing our rig, if you are in line with it, you can smell a faint tank odor. So it must be pulling something.

beemerphile1 wrote:
Waste of money in my opinion. The vent stack is nothing but an open pipe which is the same as in a house or commercial building. If you are trying to solve some issue, you should find the problem, not add on worthless accessories.

Actually, I don't see how there can be much venturi or siphon effect with these vent covers unless the toilet valve was open or there was some other way to flow air. In my opinion it's kind of like holding a soda straw straight up in the air with your thumb on the bottom, not much will flow out of the top if you placed it in a stream of air. I've just never seen the need for them or had a problem they would solve. I see 'em on a lot of rigs though!

Waste of money in my opinion. The vent stack is nothing but an open pipe which is the same as in a house or commercial building. If you are trying to solve some issue, you should find the problem, not add on worthless accessories.

I replaced the OEM vents with 360 vents and have had no issues with them. I replaced them at the start of this summer.

Mike

While I like the idea of no moving parts, I used the cyclone on my last RV without any no issues.

I've used both, and the 360 works as well if not better than the Cyclone. It's also less prone to breakage.