I am in the midst of my second conversion,& am thinking of using a Sudor Vent instead of the roof style venting. Does anybody know the criteria needed for this to work?I know they are using in mobile homes;but haven't seen them in the RVs yet?
There are vents and then there are vents. In plumbing there are two kinds of vents, the whole system vent that in a house is the main stack that runs through the roof, and then each appliance has an individual vent connection to the main stack vent. A Studor valve is a brand name for an air admittance valve, and is a way to let an appliance (sink or shower, mostly, not a toilet) have air behind water when it's not practical to install a vent connection to the main house stack vent. It lets air in to facilitate draining from the sink, it does not vent anything at all.
Venting the black or grey tanks on an RV is very similar to the main house stack in a house. It's main purpose in life is to allow poisonous sewer gas (mostly methane along with a mix of noxious byproducts) to vent up and out of the storage tank and not enter the RV through the drains or just bubble up through cracks or flaws in the tank. Its secondary purpose is to allow air into the tank when dumping. That purpose is completely separate from what a Studor valve would do on an applicance drain line.
In short, you need a roof vent for your storage tanks. It's fine to use Studor valves on your sinks to help them drain. You can do a dual purpose drain line that both drains the sinks and has an upward line to the roof for the vent, in fact that helps the sinks drain quite well.
Brian
Fixture!.........
Ive got a studor vent on my fresh water tank to let air in as the fresh tank tank drains.
As far as gray and black tanks you need to do as Brian said above and have an exterior vent for gases...etc. Our exterior vent goes out into the rear tire well and doubles as an overflow relief (its higher than the tanks but lower than the floor of the bus) just in case the gray tank or black tank overflow.
-Sean
I have what Sean has (the over flow,but no studor vent)...having said that Oatey makes a valved vent too that gets better reviews. I think that they would work, I'd try it and leave my plumbing option open to change it, having said that there are no vent pipes sticking out of my roof....
Like Brian said Studor vents are to break a vacuum to let the fixture drain that is their only purpose
Actually the main purpose of a home roof vent is to allow air into the sewer system so flushing or draining won't vacumn out the traps.
Sniff the vent on your roof, you won't smell sewer gas.
We have one that we got from HD, probably a different brand though. The kitchen sink and shower used to drain poorly, but adding this to the pipe that connects them solved the problem.
Thanks for all of this useful info!I know one thing;converting a bus without luggage bins makes a lot of difference.Hopefully the ability to go off road in tight places & fuel mileage will outweigh the hardships,I'll keep yall posted!
Bill
Quote from: gus on June 30, 2014, 02:47:19 PM
Actually the main purpose of a home roof vent is to allow air into the sewer system so flushing or draining won't vacumn out the traps.
Sniff the vent on your roof, you won't smell sewer gas.
I agree with Gus and the "P" traps under your sink and the trap in a home toilet and the rubber seal in your RV toilet is for any smells or keep any sewer gases from getting in.
The vent just acts like turning a pop can upside down and poking a hole in the bottom. A rush of incomming air basically let the contents go out faster.
It is hard to keep water in a P trap with a moving vehicle,vents on a house are also installed to keep the main sewer line gases from backing up in the house
Yes the main stack sewer gases and toilets but not the sink drain, They have their own vents. But the main reason is to release any vacuum in the drain lines.
And in a house the P traps do keep the sewer gases entering the home.
We don't have a problem keeping water in our p traps in the bus. I made them 1-1/2" long and decreased the critical distance by 1-1/2" and they stay full of enough water for travel unless we were parked on a hill in SF and thats not going to happen. LOL
Nope, a trap where the house line hooks into the main sewer line keeps out main line sewer gas from a home.
Those home vents are there 99% to prevent vacumn emptying home traps.
Traps are before the outside vent there are no traps past the vent on the outside, traps go dry that is why restaurants and commercial buildings use a primer on all floor sinks. Years ago the code would let you tie all vents into the outside vent not allowed any longer neither are double traps.
This doesn't apply to him he still needs to vent the tank someway or he will have a terrible smell every time he uses the toilet all the Studor is a vacuum breaker in sense when a vacuum is created the valve open that is why they are called AAV (air admittance valves) they will work fine for him on fixtures but he still needs a outside vent for the tank
Now I agree with Clifford there are no traps between main soil line and vent and the street sewer tap. It just drops in at 1/4" per foot toward the street.
Yes he does need a vent I wasn't saying that. If he doesn't have that his traps will drain but not much else will.
"Nope, a trap where the house line hooks into the main sewer line keeps out main line sewer gas from a home.
Those home vents are there 99% to prevent vacumn emptying home traps."
I agree with Gus on homes with a trap before a sewer line connect, but I always default my thinking to my situation on a septic tank. No trap, and the tank is vented up through the stack to the roof. Methane is technically odorless, propane is a close cousin and has an additive to make it smell, but sewer gas definitely has an perfume all it's own...
Brian
Brian,
I also have a septic tank with no primary trap. I've been on my roof many times and never once smelled sewer gas there although I have at least three vents there.
I opened the top of my tank years ago so it could be pumped out and discovered that it had a 2-3" layer of pink stuff on top that looked like plastic. It also was completely odorless, very much to my surprise. Nature is a wonderful thing!!
My theory on stinky bus tanks is that it is caused by the constant sloshing around. It never smells when it has been sitting a while.
I agree on the RV's and Maybe only in Cali but Arizona is the same as far as plumbing code supplements,.
Guys there are no traps between the house entrance and the street period. The only thing other than 4" pipe is a cleanout but no traps. Maybe where you guys are from. I am retired Building Contractor and no I don't know everything but I have installed many main entrance soil systems and that's the way it is done here. LOL
when fixtures are not in use the main soil stack vents the toilet and main lines and the sink fixtures have their own to vent them individually so the water will move out of the fixtures when used and as to not drain the P traps by Vacuum. LOL ;D
I think the house traps are on the house side of the entrance, I've seen them on building shows on tv.
Brian
Nope ;D