What’s That Smell in my RV? [How to find and eliminate RV Odors]

About the Author

Tom Davidock

Tom has been working in the outdoor recreation and environmental fields for over 25 years and writing about for the past 15. Whether it's camping, or RVing, Tom provides first-hand kneowldge of the information outdoor enthusiests need to enjoy adventures on the road. Tom has had his content featured in industry-leading news publications including RV Business, RV News, and RV.com. Tom is also the author of "Used RV: The Complete Guide for Buying a Used RV."

Does your RV smell? RVs are unique in that they combine a variety of compact pieces of equipment, technologies, and systems to make a living on the road possible. Some of these are slightly different from what we use in our homes. They also can produce a unique odor that we’re not used to smelling. This is especially true when living in such a small space, a common problem of RV life. Your nose is an excellent indicator of a problem, and if you smell something off or a foul odor, it can help pinpoint the cause of the issue. Below are some of the common RV odors that RV owners may notice and what they may tell you.

In this article, we’ll cover each type of smell in detail, provide possible sources, and suggest some solutions. However, below is a quick list of some of the more common RV orders and where they may be coming from.

RV Sell And Ordor Quick Reference List:

  1. Propane Smell: This smell indicates a potential gas leak. It’s advised to check all propane appliances and connections for leaks.
  2. Gasoline Smell: Commonly arises from the RV truck motor or generator. Immediate inspection is recommended.
  3. Decay Smell: Often due to full black or gray wastewater tanks. Regular draining and using tank treatments can help alleviate this odor.
  4. Sewage Smell: This can be caused by hard water at the campground. Installing a water filter on the city water connection is a recommended solution.
  5. Sulfur Smell: This may originate from an RV water heater or an overheating battery. Cleaning the water heater or maintaining the battery can resolve this issue.
  6. Rotten egg Smell: Indicates an electrical problem. Checking the circuit panel and electrical components for overheating or poor connections is advised.
  7. Fishy Smell: Indicates an electrical problem. Checking the circuit panel and electrical components for overheating or poor connections is advised.
  8. Burning Plastic Smell: This also points to an electrical issue. Inspecting electrical components and seeking professional help if needed is crucial.
  9.  Ammonia Smell: This usually signifies a leak in the RV refrigerator, potentially requiring a replacement.
  10. Mildew or Musty Smell: Indicates moisture problems. Using a dehumidifier and checking for leaks can help mitigate this smell.

Propane Smell

Propane has a unique and identifiable unpleasant smell. If you don’t know what it spells like and have an RV, make sure you find out. The propane smell is an additive put into the gas to notify you of a potential gas leak. If you smell propane in your RV, you should immediately turn off the gas at the tank. You may have a propane leak.

Check all propane appliances inside the RV, including your stove/oven, refrigerator, and hot water heater, if the smell is inside the RV. Try to determine if the odor is isolated to a specific area. Outside of your RV, check your refrigerator access panel, water heater access panel, outdoor grill or kitchen, and of course, right around your propane tanks.

Check all connections along the propane line, especially where it exits the tank and connects to the appliance. You can use a mixture of water and soap, or purchase a leak detection solution, to brush over the connection. If bubbles form, you found the leak. It’s essential to repair a leak ASAP before using your propane.

Gasoline Smell

If you smell gasoline while camping, you should try to find the source of it ASAP. There are two primary sources of distinct gasoline small: Your truck/motor or a generator. If it’s coming from the RV or truck, make sure you take it in for service. If it’s coming from the generator, inspect all gas lines and the carburetor and check for leaks. A flooded carburetor can fill up with gas and leak out. Also, the smell of gas can linger for a while if you have had an accidental spill or mishap.

Decay Smell

If you smell a strong decaying odor in your RV, it’s likely related to possible sources. First, a common cause is decaying food. Next is a dead mouse in your RV or walls. This odor can be very strong and unpleasant. The good news is that you can usually pinpoint the problem with your nose. If it’s food, you should be able to find it easily. However, if it’s a dead mouse, it can be challenging.

In order to get rid of the odor, you need to remove the source. Finding a dead mouse may be easy if it’s an accessible area or seemingly impossible if it’s within a wall. If you can find and remove the mouse, you should do it. If not, it’s time to turn on your fans, open the windows, and light a candle. The smell will eventually dissipate, but it can take several days or longer.

Sewage Smell

Probably the most unpleasant part of RVing is dealing with wastewater. The most likely culprit is your RV’s black tank or gray tank if you notice a sewer smell that reminds you of a septic tank odor. This holding tank odor is the strongest during the hot summer months. However, your tanks shouldn’t be a source of the constant odor. If your RV toilet smells or your sink smells, there are some steps that you can take to alleviate the unpleasant odor.

First, check to see if your tanks are full. If they are, it’s time to drain them. While it’s a good idea to use a tank treatment in your black tank, you can also use it in your grey tank(s). Rather than relying on a treatment that simply masks the RV toilet odor, make sure you get one that speeds up the digestion of solids. You can also purchase deep clean treatments, which are helpful to use between camping trips to help remove any buildup in the tanks.

If your black tank has a flush system, you should give your RV a good flush after every few tank dumps. This step will help keep your tank clean and prevent buildup and unpleasant odors. If you don’t have a tank flush system, you can purchase a handheld tool. You can give your tank a quick fill and empty with fresh water if flushing your tank isn’t an option.

A very common problem with a black tank that persistently smells is a blocked roof vent pipe. The black water tank odors and gasses are exhausted from a vent on the roof. If this gets clogged, the gasses can’t escape and will make their way into the RV. An annual inspection of your RV roof vent is a good idea. The best way to prevent RV toilets from smelling is to make sure to clean out your black tank regularly.

Your grey water tanks can smell too. This problem is especially true for your kitchen tank, which gets food particles, grease, and other organic materials in it. While you can use commercial RV tank cleaners, many people have success using hot water and dish soap. Simply fill the tank with hot tap water and a good degreaser soap and let it sit for a while. It’s best to flush it while the water is warm, so do so within an hour or so of filling. Also, don’t forget to check and clean your shower drains. They can be a source of bad odors too.

Sulfur Smell

A common source of a sulfur odor is hard water at the campground, and is likely the culprit if you’re smelling it when using water. While it’s harmless, it can be unpleasant. An easy fix is to install a water filter on your city water connection. These are inexpensive and effective, but be sure to replace them on a regular basis. Funky smells can also be avoided by filling your freshwater tanks at home and using that water while camping.

Rotten egg Smell

If your RV smells like rotten eggs, the source is likely related to one of two issues. First, if you notice a bad smell when using hot water, it’s likely coming from your RV water heater. Anaerobic bacteria, while not dangerous, can react to the magnesium or aluminum anode rod in your RV water heater. Now is an excellent time to clean your RV water heater and replace the anode rod. First, drain the RV water heater after it cools down and flush out any buildup in the tank. It may take a few rinses to get it clean. Next, you’re going to flush your water heater with peroxide, which is a germicide. For a six-gallon heater, you will use 16 ounces of peroxide. With the water heater tank empty, use a funnel to pour the peroxide into the anode rod plug in the water heater. Replace the plug and fill up your water heater. Don’t turn the water heater on when doing this.

Next, the best solution is to let the mixture sit in the tank for a few hours. The disinfection happens quickly but waiting a bit will help ensure that it’s fully clean. After you drain it, it’s time to install the new anode rod. After that, fill the water heater as usual and turn it on. You should be free of the rotten egg smell.

Another potential source of a rotten egg smell can be the battery. If a battery is overheating, the sulfuric acid in the battery is converted to hydrogen sulfide, which smells like rotten eggs. This odor is a sign that your battery needs maintenance or replacement. Don’t simply ignore it, as the problem won’t go away and can lead to other issues with the battery or your 12-volt power.

Fishy Smell

Unless you recently had fish for dinner, you shouldn’t smell it in your RV. A fishy odor is a telltale sign of an electrical problem. The first place to check is your circuit panel area. See if the smell is more pungent in this area. A poor electrical connection or overloaded electrical wire can cause this and shouldn’t be ignored. Next, check for overheated fuses and melted insulation. If you suspect a problem with the electrical system, it’s best to enlist the help of a licensed electrician to diagnose or repair this issue.

Burning Plastic Smell

Just as the fishy smell indicates an electrical problem, so does a burning plastic odor. While it’s possible that you left a plastic utensil on a hot stove, and it melted, you most likely would have noticed that. If the smell is coming from the electrical system, it means that something is getting hot enough to melt the plastic sheathing on the wire. Don’t ignore this problem. The first step is to try to pinpoint the source of the smell. When you do, inspect all electrical components in that area, including outlets, appliances, or electronic devices. While you should be able to find the problem, be sure to call an electrician or bring your RV in for service. You may simply have a loose connection or a problem with an appliance or device. Ignoring it can be dangerous and start a fire.

 Ammonia Smell

You may remember that strong ammonia smell from when your mom mopped the kitchen floor. If you smell it in your RV, the most common source is the RV refrigerator, signaling a leak. Unfortunately, if this is the problem, you may need to replace your RV fridge soon. It’s not always possible to fix this problem.

Mildew or Musty Smell

A mildew smell or musty odor indicates one thing: moisture. If you’re camping in a humid area or don’t have adequate ventilation, moisture can creep into various parts of your RV and cause a must or mildew smell over time. While it’s a common issue, left untreated, it can also lead to mold growth, which you want to avoid. Inspect your RV for water leaks too.

Another source of moisture, which will cause this smell, is an external leak. If moisture gets into the walls or sealed areas of the RV, you may not notice it until it starts to smell or you notice physical water damage. If you suspect water leaks, find and seal them.

You should dry out your RV with a dehumidifier to deal with the odor. You can help to get rid of the smell with a charcoal air filter or even an open tub of activated charcoal.

Two other sources of this odor can come from your refrigerator or air conditioner. You should be able to identify if the problem is the refrigerator. Preventing this is best achieved by wiping down the refrigerator when turned off and keeping the doors open when not in use.

If your air conditioner is the problem, a great way to fix this is to clean the filters. You can also purchase an air conditioner deodorizer, which you spray into the air intake when turned on. It may also be an excellent time to clean your coils if you haven’t done that recently.  

2 thoughts on “What’s That Smell in my RV? [How to find and eliminate RV Odors]”

  1. My smell is coming from My toilet in my rv. It’s weird because the sinks don’t smell and my second toilet don’t smell. The toilet that does constantly has a brown/yellow water. I have never smelled anything like it. Help

    • You may want to check out your toilet model. There are some dometic models that have been recalled because water gets trapped and creates a strong odor that you can’t get rid of. I’ve read posts from many people who had this problem.


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