Bad Odor Coming From My RV's Bathroom Sink Cabinet
This Could Be Causing the Bad Smell In Your RV
I have an odor in my bathroom sink in my 5th Wheel. When you open the cabinet under the sink the smell is bad. I don't know what could be causing it.
The 5th wheel is always parked in the same spot. I can't seem to figure out why only under the sink in the bathroom would be this smell.
ANSWER: Hi Ann, there could be a couple of things that are causing your odorous problem under your RV's Bathroom sink.
My first and best guess is that you have a bad Air Admittance Valve (pictured at the top of this page). Some RV manufacturers use Air Admittance Valves under sinks in place of having a roof vent for the sink.
When you drain water out of your RV's sink the draining water creates suction (vacuum effect) on the valve which then opens and allows air in the pipe which in turn allows the water to drain freely into the holding tank. When the water is done draining the valve is suppose to close tightly and seal out any sewer smell or in your case gray water tank smell from coming in the RV.
Based on your description it sounds like your valve is not sealing properly and may need to be replaced. Replacing this valve is fairly simple in that in most cases the valve just screws onto the pipe. All you will need is a big pair of slip joint pliers
to help unscrew your existing vent. To install it all you do is put some Teflon Plumbing Tape
on the threads
of the new valve and tightly screw it on.
The odor you are smelling from the gray water tank is usually from decaying food particles in the gray water itself. You might want to also start using some Enzyme Holding Tank Treatment
in both your grey and black water tanks. The enzymes in these treatments digest waste and work quite well to minimize holding tank odors as well as being environmentally friendly.
Another cause could be that if you do have a roof vent on the top of the roof for your RV's bathroom sink the vent pipe leading up to the roof has a crack in it allowing fumes from the holding tank to escape under the sink, or the roof vent is blocked by a birds nest, wasp nest, etc. and is not allowing the fumes to escape. You could have had a little varmint like a mouse or rat that has crawled under your bathroom sink cabinet and died.
Lastly, if none of the above solves the smell problem in your RV, you might want to check your RV's house batteries as they could be the source of the foul smell in your RV. If the house batteries are overcharging or low on fluid, they can produce a foul smelling gas that can be mistaken for a sewer smell.
I hope this information helps.
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