For many of us, traveling with an RV means you get to enjoy life off-grid, amongst wide open roads and the beauty of nature around you.
And the best part is with modern RVs, you don’t even need to forego any creature comforts such as running water, a working toilet, and a shower. And truth be told, a hot shower can really make the difference to your RV traveling experience.
However, when your RV hot water heater starts to act up, chances are there’s an issue that needs to be addressed right away. Some of the most common culprits for an issue with an RV hot water heater are low propane pressure, a low battery voltage, or a malfunctioning electronic control board.
Keep reading for a deeper dive into how to address this issue.
Here’s a quick troubleshooting guide to fix issues with your RV’s Hot Water Heater:
| Signs | Issue | How to solve it |
| Your hot water heater is definitely turned on, but you still get cold water coming out of your RV shower | Your bypass valves might be turned off for the water heater. This might happen when you forget to turn it back on after winterizing your RV. | Find your water heater bypass valve and turn it back on. |
| Your RV hot water does not heat as well as it is supposed to | Your outdoor shower might still be turned on and dripping, drawing cold water and mixing it with the hot water from the same pipes, reducing the temperature significantly. | Ensure your outdoor shower is shut off tight. |
| Your hot water heater turns on, then turns off by itself after a few minutes. | The heating element in your RV hot water heater is starting to corrode and go bad. | Replace the old RV hot water heating element with a new one with a heating element wrench tool and some DIY. |
| The RV hot water heater is on, but there is virtually no hot water coming out from the shower | Your propane pressure might be too low to ignite the furnace and heat up the shower. This could be the result of low outdoor temperatures, dirty propane regulator, or running other propane-dependent appliances (cooktop, refrigerator) at the same time. | Check your propane levels and ensure your propane tank and propane regulator is well maintained. Don’t use too many propane dependent appliances at once. |
| Your RV hot water heater flickers between on and off, like a malfunctioning electronic device | This could be the result of a faulty electronic circuitry board in your furnace. | The ECB controls the ignition process of the furnace, so if there’s a problem with the ECB, you’ll probably have to replace it with a brand new ECB. |
Why does my RV hot water heater start and stop?
There are 4 main issues you need to look out for whenever you face a hot water heater issue in your RV
- Low propane pressure
The propane in your RV is responsible for operating an array of appliances in your rig. If you’re trying to run your hot water heater in cold, winter temperatures, you will find that the imminent decrease in propane pressure causes your hot water heater to heat very slowly.
A dirty propane regulator can also be the cause of low propane pressure, leading to issues with your hot water heater. This is more common than you think, so you won’t have to worry about replacing it with a brand new one you can find easily in stores.
- Low battery voltage
The RV battery runs many of the electric appliances necessary for a life off-grid in your adventure mobile, so if your hot water heater seems a bit off lately, chances are it might be an issue with the battery that is causing the issue.
Your RV’s hot water heater has a furnace fan that runs on 12v DC, and this is taken straight from your RV’s battery bank. Now, this isn’t a problem if you’re in an RV campsite and you’re plugged into the mains, but when you’re out in the boondocks, your hot water furnace can very quickly wear down your battery in just a few hours. This causes your hot water heater to turn off and on as your RV battery struggles to adjust to the low power coming into its system from inadequate battery voltage.
If this is the case, you should add more batteries to your RV system – this might need some electrical experience, so call a professional if necessary.
- ECB issues
The ECB is the heart of all things electronic in your RV. It runs the lights, power, and most importantly, your hot water heater’s furnace. If there is an issue with the ECB, the instructions it gives to your hot water heater becomes muddled, causing the furnace to shut off and relight erratically when in operation. This causes the issue of hot water heaters starting and stopping.
The best solution at this juncture is to buy a new ECB and replace the old one with the new one. Consult your RV manufacturer’s handbook for instructions, as this should be quite a straightforward job.
- Furnace igniter malfunction
Lastly, the furnace igniter itself might be the problem. They are consumable parts, meaning that they eventually go bad after a few years. However, they can prematurely malfunction through careless handling.
If your furnace igniter is the issue, simply find out the brand and model of your current furnace, and look for a replacement furnace igniter on Amazon, or your local RV supplies store.
Other reasons why your RV hot water heater starts and stops
Apart from those 4 main reasons listed above, there are some more things you should look out for to get a full diagnosis of why your RV is facing this issue.
A thermostat issue is a hidden issue that most people would not know about. Thermostat problems are not clearly visible from the outside, as they are installed deep into the plumbing system, and there are no visual cues to tell you whether something is wrong with it or not.
Using a multimeter, check whether your thermostat is working and replace it immediately if it doesn’t. If you’re new to electronics and plumbing, don’t do this yourself without prior safety measures, as you might run the risk of electrocution via live wires.
Heating elements are found in electric hot water heater systems – these work the same way in which an electric kettle would, by using a heating element that heats up to a high temperature, thus heating up the water that surrounds it.
Over time, heating elements corrode and go bad. This means you’ll need to replace it with a new one.
Should I call a pro to fix my RV hot water heater?
RVers are people who know what they want – they want adventure and to be out in nature, while enjoying the comforts of home, such as a kitchen, a comfortable shelter, and a hot shower every now and then.
If none of the above tips have helped you to solve your RV hot water heater problem, chances are you’re going to need the expertise of a professional to deal with this problem for you.
They have the experience to successfully diagnose any issues with plumbing, electronics, and hot water heater systems in RVs, and fix these issues promptly. With a professional at the helm, this also means that you’ll get your hot shower back sooner rather than later – which is always a great feeling!
