Community Forums

db4570 · 02-08-2023, 04:32 PM

Just bought a new camping trailer after camping in tents and a popup for many years. So the RV toilet is a new thing for us.

It seems like there is a lot of discussion about RV toilet challenges. Mostly preventing smell.

Why is this? I understand it may be because there is only a (possibly leaky) rubber valve between the bowl and the waste tank. But why are they using this method in the first place, instead of a regular residential type toilet with a simple water trap?

I must be missing an obvious reason.

TandW · 02-08-2023, 04:51 PM

There is no trap in a typical RV toilet to deter unpleasant tank odors from entering the living space during a flush cycle, especially during times that a ventilation/exhaust fan is in operation.

Old-Biscuit · 02-08-2023, 04:54 PM

Need a tank for residential....
No tank needed for RV design toilet...just water supply, vacuum breaker and bowl seal

RV toilets are not that big of a problem

The RV toilet on my 2007 Trailer is still all OEM
Same bowl seal, same water valve, same vacuum breaker etc
Works just as well today as it did 17 yrs ago

Just a little routine cleaning and lubrication of seal.
During non-camping I pour Olive Oil into bowl...just enough to cover the seal

I've had more problems with Residential Toilets then any RV toilet

hypoxia · 02-08-2023, 05:17 PM

Quote:

Originally Posted by Old-Biscuit

Need a tank for residential....
No tank needed for RV design toilet...just water supply, vacuum breaker and bowl seal

RV toilets are not that big of a problem

The RV toilet on my 2007 Trailer is still all OEM
Same bowl seal, same water valve, same vacuum breaker etc
Works just as well today as it did 17 yrs ago

Just a little routine cleaning and lubrication of seal.
During non-camping I pour Olive Oil into bowl...just enough to cover the seal

I've had more problems with Residential Toilets then any RV toilet

wildtoad · 02-08-2023, 05:28 PM

Typical house toilets use significant amounts (2+ gallons, some toilets more, some less) of water per flush. RV toilets use very little water for liquid only flushes, a bit more for solids. It’s all about holding tank management. If on full hookups, not a real issue.

pasdad1 · 02-08-2023, 05:29 PM

A macerator toilet is another RV type of toilet. I prefer this type. Never any smell while flushing, and it grinds up everything making for a easier to manage black tank (I think anyway.)

Yes, it uses more water than a drop toilet, but this also helps the black tank, as more water to solids ratio is a good thing.

pushtrk99 · 02-08-2023, 05:29 PM

If it smells maybe time to replace with new one -not expensive and and very easy to change-We chose to replace ours for sanitary reasons, was one of the better modifications we did

deandec · 02-08-2023, 05:44 PM

Interesting re the odor issue.

Our electric. direct drop toilet flapper ceased to operate in the open position.

No smell from the toilet in the coach during the 6 days needed to have the part replacement shipped to us. Pleasantly surprised by this.

Maybe an updraft changes the odor status?

Jkwilson1989 · 02-08-2023, 09:27 PM

A residential toilet would likely empty the trap when the rig was moving. Then there would be nothing blocking the smell

db4570 · 02-08-2023, 09:39 PM

Quote:

Originally Posted by TandW

There is no trap in a typical RV toilet to deter unpleasant tank odors from entering the living space during a flush cycle, especially during times that a ventilation/exhaust fan is in operation.

Yes, but why?

[QUOTE=Old-Biscuit;6419413]Need a tank for residential....
No tank needed for RV design toilet...just water supply, vacuum breaker and bowl seal

Yes, but why? Why not a tank and trap?

Quote:

Originally Posted by wildtoad

Typical house toilets use significant amounts (2+ gallons, some toilets more, some less) of water per flush. RV toilets use very little water for liquid only flushes, a bit more for solids. It’s all about holding tank management. If on full hookups, not a real issue.

I have a regular residential toilet that is .8 GPF. I am reading that is about the average RV flush.

I am just wondering why a trap couldn't be incorporated into an RV toilet design. Seems so simple compared to a valve, seal, etc.

SteveJ. · 02-08-2023, 10:06 PM

A tank would leak out the top during braking and other maneuvers. The syphon trap may also empty.

We use about a cup to a pint of flush water for liquids and about double or so for solids in our drop toilet, a lot less than the .8 that your resi toilet uses. When boondocking any water not wasted is a good thing as tank capacities are finite.

AllegroD · 02-08-2023, 10:28 PM

Yep! Do not want a tank full of water bouncing down the road.

Mudfrog · 02-08-2023, 11:54 PM

[QUOTE=db4570;6419556]Yes, but why?

Quote:

Originally Posted by Old-Biscuit

Need a tank for residential....
No tank needed for RV design toilet...just water supply, vacuum breaker and bowl seal

Yes, but why? Why not a tank and trap?

I have a regular residential toilet that is .8 GPF. I am reading that is about the average RV flush.

I am just wondering why a trap couldn't be incorporated into an RV toilet design. Seems so simple compared to a valve, seal, etc.

The simple answer is,, there's no need for it. A smell won't come up through the bowl unless the bowl seal goes bad and isn't holding water. This doesn't happen all that often. Mine finally got to where it wouldn't seal well but this was after more than 18 years of service.

Personally, I like being able to adjust how much water I use for each flush. Number one gets a flush with just enough to rinse the bowl. Nowhere near .8 gpf. Number two uses more but probably not that much either!

Skilletface · 02-09-2023, 05:55 AM

Quote:

Originally Posted by db4570

Just bought a new camping trailer after camping in tents and a popup for many years. So the RV toilet is a new thing for us.

It seems like there is a lot of discussion about RV toilet challenges. Mostly preventing smell.

Why is this? I understand it may be because there is only a (possibly leaky) rubber valve between the bowl and the waste tank. But why are they using this method in the first place, instead of a regular residential type toilet with a simple water trap?

I must be missing an obvious reason.

While traveling most if not all water in a sanitary fitting would be siphoned out at least in to the black tank or maybe splash out.

The simplest fix to control RV toilet odors is to add about “1/2 of water on top of the waste gate valve after completing your business. Lightly stepping on the low mounted lever with out opening the waste gate valve will spray water into the toilet bowl.
Also using a black tank treatment will help with odor control and make sure all of your roof vents are secured down while in transit this will insure that the gasses being released through the plumbing roof vent will not be drawn into the RV.