RV Water Heater Troubleshooting Tips

Have you ever woken up in the morning, eager to start a pot of coffee so you can get the fuel you need to get through your day, only to find the water is cold instead of warm? Maybe you decide to take a shower instead, but the water in there is also like ice!

What is going on?

Most likely, you’re having an issue with your water heater. Just as you can experience such a problem at home, water heater troubles can also affect your RV. This becomes especially troublesome in the colder weather when hot water is an essential.

Repairing a damaged or broken water heater can be expensive. Luckily, most issues that affect your water heater aren’t necessarily serious. In fact, you may even be able to fix a few of these yourself.

The repair process begins with troubleshooting. In this article, we’re going to go over troubleshooting methods for the most common water heater problems. Of course, if it’s better that a professional fix the issue, we will mention that as well.

Problem: Your water heater stinks.

Every time you run the sink or take a shower in your RV, you can’t help but notice a terrible rotten egg kind of stench. It’s really pretty gross. You tried ignoring it for a while, but now it’s gotten to the point where even an air freshener in the vehicle can’t combat it.

Troubleshooting: It’s time to give your water heating system a flush.

The water heating system in your RV isn’t perfect. Sulfur water and hydrogen sulfide can get backed up and thus gunk up your water heater with bacteria. When this happens, the aforementioned reeking stench starts to develop.

To get rid of the stench, access your vehicle’s heater tank. Release all the water from it via the drain plug. Now, in most instances, the water should release without any issue, but if you’re having a hard time, it’s probably because of the temperature relief valve. Check this and then try again.

Next, mix together some household liquid bleach and chlorinated water (with a ratio of 1:230 for the bleach). Hydrogen peroxide is a good substitute for chlorinated water, but make sure it’s three percent (the recommended ratio of hydrogen to water is 1:160). Alternately, you can also combine water and vinegar (with a 2:1 ratio).

Pour this mixture into your empty heater tank and wait. After a couple of hours have passed, you can start the flushing, passing out this mixture. The chemicals used in the flushing mixture are meant to cleanse the unpleasant scent you were experiencing.

Problem: You don’t perform routine maintenance.

If this was the first time you’ve performed a job like flushing the system, that’s not good. Part of your responsibility in owning an RV is performing routine maintenance on the vehicle and its components, including the water heater.

Troubleshooting: Start a regular maintenance schedule.

When you’re about to retire your RV for the winter, make sure you winterize the water heater. This will keep it in good condition during the off-season, so when you return to your vehicle in the spring, you won’t have any headaches to deal with.

Also, in terms of draining and flushing the system, make sure to do this twice a year at least.

Problem: The ignitor is acting up or not working at all.

The ignitor is a crucial component of your water heater. Without it, you might as well get used to cold showers and cooking, because you’re not getting much if any hot water.

Lately, you’ve been having problems with your ignitor. If it will light at all, it doesn’t stay lit for long periods, or it takes you a while to light it.

Troubleshooting: Try assorted means of repair.

There is a slew of reasons you could be dealing with this issue with the ignitor. Here are a few tactics you can try:

  • Locate the electrodes near the ignitor. Make sure the poor ground around these isn’t loose.
  • Check the gas valve and the ground wire around this. Once again, test that this isn’t loose and fix it if it is.
  • Consider buying another thermostat if the readings are wildly different each time.
  • Inspect the electrode insultation. Is this damaged in any way, such as cracking? If so, change it out for some fresh insulation and see if that fixes the problem.

Problem: The pressure release valve won’t achieve high pressure anymore.

Speaking of important components of your RV’s water heater, the pressure release valve is another necessity. Without this, the pressure in the hot water system would build up so high that the heater would probably explode or at least start a pretty big fire.

This valve only kicks in at a pressure of 124 pounds per square inch (PSI) and sometimes 150 PSI. At this point, the water heater is about 210 degrees Fahrenheit, which is the max temperature the heater should reach. Any hotter and it becomes a safety hazard.

Your issue is that the valve seems to have condensation around it. Is it leaking? If so, what can you do?

Troubleshooting: Change out the air in the pressure release valve.

You should prioritize repairing this issue as soon as you spot it, as again, a malfunctioning or failing pressure relief valve is a safety hazard.

The valve liquid you’ve discovered is not necessarily anything to panic over. The older your pressure release valve gets, the more likely this is to happen, because air begins to move towards the hot water tank’s top rather than where it should be.

The best thing you can do is change out the air. To do this, unplug or otherwise power down your water heater. Now wait a while to make sure the water isn’t hot. Once you know it’s safe to go near the water, check the levels in the water heater.

Access the faucet’s release pressure as well as the water supply, which you want to power down. After a few minutes, restore the water to the tank and the air pressure issue should be fixed.

Problem: Sooting is occurring.

Sooting refers to the accumulation of soot, which is made of amorphous carbon and is black in color. You’ll only have to deal with soot if ignition within the tank does not fully occur.

Troubleshooting: Check the main burner.

The main burner is most likely the culprit that’s leading to the soot accumulation. It could also be the exhaust grille or the U tube though (no, not like the popular social media video platform, although close).

To diagnose and treat the issue, first you should look at your gas supply. Is this close to full or almost empty? If it’s the latter, top off the supply. Next, check your flame spreader, air shutter, valve, and main burner alignment, looking for anything off-kilter.

Lastly, you can look for obstructions in or around the exhaust grille, U tube, or main burner. Hopefully one of those troubleshooting tactics does the trick!

Problem: The water is moving very slowly through the tank.

Maybe you have no issue with the water temperature, but rather the speed at which it moves (or lack thereof!). You may not necessarily see this issue, and sometimes you don’t even hear it. You just wait and wait and wait to wash your hands or take a shower or even get some water to put on a pot of coffee.

Troubleshooting: Perform a vinegar soak.

So what’s the reason your water is moving at the speed of molasses (and even that is being generous)? It’s likely the faucet screens have developed mineral deposits. These deposits prevent the water from flowing at normal speed, which causes the aforementioned annoying delay.

You can easily fix this issue with a vinegar soak. First, pour vinegar into a large cup. Microwave the cup for 30 to 60 seconds. You want to warm up the vinegar but not make it hot. You also want to avoid accidentally boiling it.

Once the vinegar is at the desired temperature, cover the faucet screens in this mixture and let it sit for a few minutes. You want the calcium deposits to break down, which can take time, so be patient. You may even have to pour the mixture a few times to get rid of the deposits entirely.

Problem: The electrodes won’t spark.

Above, we talked about electrode insulation. Although this sounds like complicated scientific talk, it isn’t. Your water heater comes with what’s known as an anode rod, which is a type of electrode. That said, the rod can lose its force over time, breaking down and turning from silver to a coppery shade.

All this and more may lead to problems with the electrodes failing to spark.  

Troubleshooting: Check the electrode connection and wipe down electrodes.

You can try a slew of troubleshooting options, one of which will hopefully take care of your problem. Those are:

  • Test the circuit board. Is it working? If not, it’s time for a new one.
  • Check the insulation of the electrode. This may become loosened or cracked over time, in which case the electrodes should be changed out for new ones.
  • Look at the circuit board wire connections and make sure these are all tightened.
  • If the electrodes are dirty, wipe them down carefully and gently.
  • Create a gap between electrodes when repositioning these. The electrodes should not be on top of one another or too close to each other.
  • Check the connection to the main burner and the electrodes. Is this tight? If not, make sure it is.

Problem: The propane fails to turn on.

Without propane, you also won’t get sufficient heat to your water heater. This can lead to the aforementioned unfortunate issues of cold showers and a generally unpleasant experience on your RV.

Troubleshooting: Unclog the burner nozzle.

Fortunately, the repair for propane failure isn’t too difficult. There are a few issues you should keep an eye out for, both now and in the future.

One of those is loose wires. Once a propane nozzle’s wires loosen, ignition may not occur. If it does, the water heater may not stay lit for long.

Corrosion is another issue to be aware of, especially if you can hear the ignition is trying to kick on (it’ll make a clicking sound). If it’s a serious case of corrosion, you may have to replace the entire burner.

Sometimes the air line may get clogged, especially if you left your RV in a car park over the winter and you’re just dusting it off in the spring. If so, you can rid the line of air via bleeding, which is a slow release technique.

Lastly, you should check the burner nozzle and the exhaust area. Sometimes dust, debris, dirt, and even insects will back up the gas supply tube, which leads to burner nozzle failure. Here’s a fun fact: insects such as spiders actually enjoy the propane scent and actively seek it out.

Problem: The water comes out cold.

Uh-oh. The worst has happened. Despite that you let the water heater sit for a while so it could warm up again, the water is coming out cold every time. It’s been days now and you’re eager for a hot shower.

Troubleshooting:  Look at the bypass valve.

If it’s not any of the issues we’ve covered so far, then it’s time to take a look at your water heater’s bypass valve. You should have turned this on before you left your RV for the off-season, as this valve aides in winterizing the water heater.

If you did, there’s a chance you didn’t set the valve on when you got back to your RV. That could be your issue.

Another tactic you can try is looking at the faucets. How many of these are open and running? If the answer is anything but one, that could be why the water temperature is so chilly. When you run multiple faucets, the first faucet will produce hot water while the other produces cold water. There can also be an overlap, especially once the hot water runs out. Then both faucets just run cold.

As a rule of thumb, you should always have one faucet running at a time and no more than that. Otherwise, you’ll be likely to have more cold-water days in the future. No one wants that!

Problem: The water heater is too loud.  

Your water heater used to operate soundlessly. In fact, besides twice-a-year maintenance (or more), you didn’t think about it much at all because it was that quiet. Now, though, each time you use hot water, the heater is whistling, popping, or even screeching or whistling.

These sounds are annoying, sure, but they’re also indicative of a bigger problem. In fact, each one is a sign of a different issue!

Troubleshooting: Various tactics depending on the type of water heater sounds.

Okay, here’s how you can solve the issue of each sound:

  • Whistling noises: If your water heater whistles as it works, go to the check valve. Look for any dust, dirt, or other debris that can get clogged up in there. Remove said mess and the whistling should stop.
  • Popping sounds: If it’s more like a popping that you’re hearing, this could be because of mineral deposits. Whether you have a gas or an electric water heater, mineral deposits can form and lead to that unwanted clunking and popping. Remove mineral deposits following the vinegar troubleshooting instructions outlined above.
  • Screeching or whining: From screeching to whining and more, these noises all have one thing in common: they’re very high-pitched. That pitch tells you to check for signs of corrosion as well as calcium or limescale growth. A corroded water heater might be done for, but you might want to call a pro just to be sure. Water conditioner, such as this one from Limetron, will clear away limestone deposits.


Your water heater is an integral part of your RV, keeping the water nice and toasty for showering, cooking, and more. If something goes awry with the heater, your first inclination may be to panic.

Most of the issues you’re dealing with are incredibly common and thus easily fixable without the need to call in a professional (in most cases). By following these troubleshooting tips, you shouldn’t have to worry about your water h

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