You’re sitting in your RV relaxing, reading, or enjoying a movie when you notice a foul odor lingering inside. After doing some sniffing around you realize it’s coming from the kitchen sink. Here are six reasons why your RV kitchen sink might smell bad, and how to fix it.
Food Build-Up Around the Drain
No matter how hard you try to prevent food from going down the drain, it’s almost impossible to prevent it completely. Over time grease, oils, and gunk can start to build up just inside your sink drain. Even impurities in the water can contribute to the build-up, and this slimy crud will eventually start to stink.
To remedy this problem, you should do a thorough cleaning of the drain, and the sink strainer every month or so to prevent that gunky build-up.
Using a narrow brush or pipe cleaner, and hot, soapy water, scrub down inside each hole of the drain, building up a good lather. Try to get the brush down along the insides of the pipe as much as possible, but your main goal is to clean that drain.
Also, scrub the underside of the sink strainer with a small brush. A toothbrush works great for this. Give it a good rinse with hot water. It’s easiest to do this when you have full hookups and can run as much hot water as needed.
Dry P-Trap
Continuing down the drainpipe, the source of the odor could be caused by a dirty or dry p-trap. The p-trap, called that because it is shaped like the letter P, is there to trap a small amount of water in the pipe. This water prevents odors from coming up from the gray tank, up the drain, and into your RV.
If you notice a smell right after dumping your gray tank and before you have run any water in the sink, the smell could be caused by a dry P-trap. The p-trap can dry out for several reasons.
- Evaporation – water will evaporate from the p-trap when your RV is in storage or if the sink hasn’t been used for at least a month.
- Leaky pipe fitting – check for small, slow leaks where the P-trap connects to the pipes. Over time the seals can harden and leak. These connections should be hand-tightened only. Using a wrench can cause the plastic to crack, which will also cause a leak.
- Emptying during travel – driving from campsite to campsite, especially on rough roads, can sometimes cause the water in the p-trap to drain out.
The simplest solution in these cases is to run some water in the sink and allow the p-trap to fill back up. Check for any leaks around the pipe connections.
Dirty P-Trap
If you still have odors coming from your sink even when there’s water in the p-trap, then you may need to go the extra step and clean or replace the p-trap itself.
To clean the p-trap, remove the pipe by loosening the two coupling nuts. Be ready with something to catch the water when you remove the pipe. Using a brush, scrub the inside of the pipe.
Once clean and rinsed, re-attach the pipe and hand tighten the coupling nuts. Run the water and check for leaks.
Never use harsh chemicals to clean the train pipes as this can damage the pipes and your holding tank. Instead, use a mixture of vinegar and baking soda and pour it down the drain. The mixture will foam and bubble, eating away the gunk lining the pipes without damaging them. Then follow up with hot running water.
Bad Anti-Siphon Trap Vent
Also called a check valve or In-Line Cheater Air Admittance Vent, the anti-siphon valve allows air to enter into the pipe system under a certain amount of suction pressure, usually when you empty your gray tank. It contains a rubber stopper that closes when not under pressure, to prevent odors from coming out of your gray tank and into your RV.
Over time the rubber seal can go bad, dry up, or not fit properly. This will allow odors to escape into your RV. To fix this problem, unscrew the valve and check the rubber seal. If it is worn out, simply purchase a new valve and replace it.
Anti-Siphon valves are available at most home improvement stores, on Amazon, or at Camping World.
Gray Tank is Full
Often, when an RV’s gray tank is completely full, a foul odor will come up from the kitchen or shower drains. This is a good indication that your tank needs to be dumped.
RV tank sensors over time can become dirty and are no longer 100% accurate. You should try to become familiar with how much water you generally put into your gray tank during an average week.
Gray Tank Needs Cleaning
If you still notice an odor after dumping your gray tank, it’s time to flush and clean the tank. Bits of food, oils, and grease, can build up in your gray tank. The build-up needs to be broken loose and flushed away.
One way to do this is to pour 1 cup of automatic dishwashing detergent down the drain and fill this tank up 1/3 with water. The dishwashing detergent is good because it’s designed to remove grease and doesn’t create suds. Then, drive your RV around for at least 30 minutes before dumping the tank. Obviously doing this during a travel day is make it much easier.
One thing you don’t want to do is to use regular dish soap to clean out the gray tank. While some will go into the tank from washing dishes, it is not recommended to pour a large amount all at once. Liquid dish soap is designed to create a lot of suds.
Another way to clean the gray tank is to use a hydro flush attachment, like the Rhino Blaster, on your dump valve and flush out the gray tank a few times to remove any remaining food particles or built-up gunk.
Wrap Up
With proper maintenance and upkeep, your RV kitchen sink should remain clean and free from nasty odors.