Have you noticed that your hot water heater smells like burning dust or plastic? These and other water heater smells can be an indication that your hot water system needs attention. Don’t ignore these water heater odors—they’re signs of potential trouble that could turn into fire hazards. Learn why your water heater smells like gas or burning, and what to do about it.
1. Burning Plastic or Rubber Smells
If your water heater smells like burning plastic or rubber, it may mean that rubber or plastic components are overheating and burning. This could be due to overheating of plastic parts such as switch surrounds or insulating wire coatings or of rubber parts such as:
How to fix it: Try to pinpoint which parts are causing the smell. You may notice parts that look burned or melted, or warped out of shape. Replacing any damaged pieces is half the fix, but the other is to determine what’s causing them to burn in the first place. If you’re unable to locate the source of the problem, it’s time to call in a plumber for expert help.
2. Electrical Burning Smells
When a water heater smells like electrical burning, it means one or more electrical parts have failed or are overloaded. With hot water heaters, it’s typically one of two things: the electrical contacts or the flame rod.
- Electrical connections can erode over time. This can cause them to overheat and start arcing, causing electricity to discharge incorrectly. Arcing also causes heat to build up at the electrical connections, resulting in a burning smell.
- Flame rods can sustain damage over time. If the damage is severe enough, the rod may short out, leading to excess current that heats up the wiring and causes burning smells.
How to fix it: Electrical issues are potential fire hazards and should be fixed as soon as possible. According to the National Fire Protection Association, 10% of all home heating fires are caused by water heaters. To ensure your water heater is repaired safely, it’s best to call in a licensed plumber to deal with these issues.
3. Burning Dust Smells
Water heaters tend to be located in out-of-the-way spots where they easily accumulate dust. Over time the dust can form a thick enough layer that you notice the smell of burning dust coming from your water heater. Fortunately, there’s an easy solution.
How to fix it: Clean and dust your water heater regularly, and those burning dust smells will be a thing of the past.
4. Sulfur or Rotten Eggs
Sulfurous smells can be caused by a number of things, including bacteria and chemical causes.
Sacrificial Anode Rod
If you have a tanked water heater, that sulfur odor or rotten egg smell can be a sign that it’s time to replace the anode rod. Also called the sacrificial anode rod, this device is a metal rod that sits inside the tank and protects against rust and corrosion. As the rod corrodes, the metal reacts with sulfates present in the water, producing hydrogen sulfide.
How to fix it: Anode rods need to be replaced every one to two years. This can be a DIY job if you have some experience. If you’re not confident about doing it yourself, it’s better to call in a licensed plumber.
You can prevent this problem in the future by replacing your magnesium rod with a zinc or aluminum-zinc alloy rod. Zinc doesn’t react with sulfates in the same way magnesium does, so it helps prevent sulfur gas from accumulating.
Some kinds of bacteria use sulfates as a nutrient source and produce sulfur-containing gases. If these bacteria are present, the water may smell like sulfur or have a rotten egg odor. Most often, this is caused by water stagnation.
How to fix it: If the smell is due to stagnant water, flushing and sanitizing the water tank is usually the simplest solution. To prevent the problem from happening again, avoid leaving hot water sitting in the tank for long periods of time. If you’re going away on vacation, for instance, turn the water heater off while you’re gone.
If both your hot and cold water smells, it means your home’s incoming water supply must be treated. This is often the case for homes that use an alternate water supply, such as well water that isn’t chlorinated or times when the lakes turn over and start to smell fishy. Treating the problem may require installing a water treatment system or a reverse osmosis system.
5. Gas Smells
If your gas water heater smells like gas, there’s a chance you have a gas leak. If this is the case, don’t delay: Evacuate your home right away. Once everyone is safely outside, call your utility company or plumber for help.
If you have any reason to suspect a gas leak, don’t wait around to figure out where it’s coming from or try to fix it. Natural gas is hazardous to your health, as well as being combustible. And do not turn on or off any switches in your home, as a spark can act as an igniter.
Eliminate Unpleasant Water Heater Smells: Call CW Service Pros
Are water heater smells ruining your showers or leaving laundry and dishes smelling unpleasant? For help eliminating water heater smells like burning or sulfur, call CW Service Pros. Our licensed plumbers can quickly detect the source of the problem and find a solution that works, including water heater repair or replacement.