"Folgers" P-Trap Solution May Help Tank Stink

For those whose RV is connected to a drain most of the time, you probably keep your gray water valve open. At times a smelly little problem arises: Sewer gases can come back up the sewer hose, into your gray tank, and slow migrate their way up the through the tank and out the roof vent. At times those same evil essences can somehow re-infiltrate your RV with a negative impact on your olfactory organs.

Worse still, if there are any "vague" connections in your gray water venting system, those nasty little essences can also make their creeping way out, carrying not just the odor of gray water (as bad as that is) but with a direct connection to the city sewer (or local septic system) that REALLY horrific scent of black water can invade your premises.

What to do? Enter the Folgers P-Trap solution: If you leave your sewer hose connected and the dump valve open, stick a P-trap between the sewer and you. Simply obtain a coffee can (or a large rock, and make a bend in your sewer hose, as illustrated in the photo here. Gray water will advance over the bend, but the water trapped in the hose on the "rig side" of the coffee can will prevent the odoriferous fumes from crossing over.

Mind you, when you dump your black water you'll want to temporarily remove the coffee can to allow a free-flow of black water, etal, to make the trip down the sewer unimpeded.

Rotating Holding Tank Vent Really Does the Job

We blogged earlier about dealing with holding tank odors through better tank management. Here's another trick the nose knows works: Those fancy wind-driven rooftop tank vents. Here's the deal: The standard OEM vents are not much more than tricky caps to keep the birds out. The don't allow a great deal of air flow to allow the essence of holding tank to escape; at times pressure actually puffs it back down into the tank, and finding any other escape route--sometimes into the coach.

The model we tested, an RV 360, puts a fin atop a rotating vent cap. As the wind blows, the "emitter" side of the vent cap is on the downwind side, causing the wind pressure to suck those narsty gasses out of the holding tank. Does it work? We found our stink situation really alleviated, as have many other RVers.

These systems are not difficult to install, although they can be a bit messy, depending on the type of sealant you use on install. Be sure to wear grungy work clothes. The instructions included with the system are clear enough, but on one install, the instructions left us high and dry. The existing vent pipe was located right next to the rooftop air conditioner unit--and if the 360 vent were placed at rooftop level, it would have bumped right into the a/c unit. Not only would the wind be cut, in some cases the vent unit would simply not turn freely.

We worked around this simply: Using PVC pipe the same diameter as the existing vent pipe, we glued the "bell" end of the new pipe over the top of the existing vent pipe. With this "extension" in place, we attached the 360 vent to the top of our extension. No obstruction problems, no holding tank stink. Total time? About an hour and a half, including the time it took to figure out the "work around." Tools are easy: Putty knife, screwdriver, and a hacksaw if you need to rig an extension.

You can find the 360 at most RV suppliers, including Camping World.

The Nose Knows Holding Tank Stink

"I stink, therefore I am," says my philosopher. He lives under my RV, and travels everywhere with me. He is a rather nondescript fellow, about six feet tall, four feet wide, and a thin six inches thick. He seems to prefer a dark suit, in fact, every time I lay eyes on him, he's laying about, clad in the black skin of plastic suited to folks of his kind. Although he is never invited inside, from time to time he does--in an awful way--make his presence known. He is a windy fellow, and many of my associates simply state, "He's full of it." And so he is, for my friend the dark philosopher is a black water holding tank.

As much as I try and force him to keep his ideas to himself, he does on occasion air his opinions. Usually my better half, she with the more sensitive of noses, is the first to complain. "You've got to do something about this!" she'll yelp, making a rapid exodus from our little room of rest. It is perhaps the torture stake of the male species, this job of being resident problem-solver.
To keep my dark friend happy, I feed him a gruel of enzymes and bacteria, guaranteed to be "earth friendly," and to relieve my friend of unwanted odors. To be sure, when it doesn't work, I'm not sure who makes a bigger stink--my tank, or my wife.

Holding tank odors are a bane for RVers, but often they can be simply cured. First, we have not enough space to discuss the relative merits of holding tank chemistry--check a future blog for that--but if your tank "sits" for a long time without motion, say parked in an RV park for months on end--a sour tank is often a result.

I know I said I wouldn’t go into depth on holding tank chemistry, but I swear by the natural, enzyme and bacteria friendly variety. When my "green black water tank" goes sour, here’s the first fix: Dump the black water tank and refill with fresh water--and dump it again. Now chuck a pound box of baking soda down the toilet and again, REFILL the black tank with water. Let it sit overnight and dump it again. Now recharge the tank with your bacteria friendly treatment following the maker’s recommendations.

My philosopher friend urges that dogged determination may be required to track down and cure a smelly problem. At least that's what I translate--"When pesky pots pose proboscis problems, probably pointed poking will prevail." 'Nuf said.