No matter what time of year it is, unexpectedly stepping into an icy cold shower is not a pleasant experience. RV water heaters are notorious for breaking down. Fortunately, they’re also relatively easy to fix if you know where to look.
In this guide we’re going to break down the most common reasons RV water heaters fail, and help you troubleshoot your camper to keep the hot water flowing.
Why is my RV water heater not heating?
Before diving into the details, these are the most common reasons your water heater is not working:
- Pressurized water is not reaching the inlet
- Propane is not turned on
- Leak in the LP gas line
- Ignition switch is not lighting
- Electricity is not reaching the water heater
- Bad circuit board
Getting Water To The Heater
In order for your water heater to work, it needs water!
There is a pressure relief valve located at the top of your heater. Unscrew it, and see if any water comes out (PS: do this carefully in case there is hot water inside).
If there is no water, check that your water heater bypass valves are open. This is an easy thing to forget after winterizing your RV.
Check The Propane Tank
Make sure the propane tanks are full and working. You can try lighting the stovetop to double-check that the propane is flowing.
Many propane-powered water heaters have an Overfill Protection Device (OPD) installed which will shut off flow to the tank when it detects a rush of propane. This can happen if the lines were de-pressurized.
To re-pressurize the lines: Close the propane tank valve, turn off all propane-powered devices, re-open the valve.
Check Propane Lines For Leaks
Maybe your water heater is not getting a proper flow of propane.
Check for leaks around the fittings using soapy water. If the water bubbles up, you have a leak! You can also conduct a smell test to check for signs of leaky propane.
Ignition Switch and Electricity Problems
Manual Valve Gas Water Heaters
If your manual water heater will not light, check the thermocouple to make sure it’s clean and attached tightly to the control valve. It should also be centered in the pilot light flame. Clean the pilot burner, orifice, and tube.
If the ignition still will not light, you probably have a bad thermocouple or control valve.
Direct Spark Ignition (DSI) Gas Water Heaters
Ensure the igniter is cleaned and properly aligned. Then, make sure power is reaching the water heater and circuit board using a multimeter.
One of the most common causes of failure are limit switches that prevent the
heater from overheating. Some switches have a push to reset button on those sensors but many do not. If the switches fail they prevent the heater from lighting.
Check the circuit board fuse. If it’s intact, the circuit board may need to be replaced. You can find circuit board testers at many RV service centers.
Dinosaur Electronics is one of the leading circuit board manufacturers. They sell replacement boards for most of the major brands and electronics.
Adjustable Flame Shutters
Some water heaters have an adjustable flame shutter that determines how much oxygen the flame gets.
The flame is less stable when it’s open all the way. If you close it too much, you won’t get a strong enough flame and it will look yellow instead of blue.
You want to keep the flame shutter somewhere in the middle for a steady, hot flame.
Make Sure Your RV Hot Water Heater Is Clean
A common problem is spiders or webs in the burner tubes. Clean these with a small bottle brush or blow it out using an air compressor.
If your water heater doesn’t light reliably remove the motor assembly from the heater and clean the electrodes and burner with a wire brush. Check that the electrodes are 1/8 inch apart.
Replace Your Corroded Anode Rod
Water heater anode rods should be replaced on an annual basis. It gets corroded before the tank does so you don’t damage your camper. If the anode rod becomes too corroded then it’s not doing a good job of protecting your tank.
While this part won’t effect the water heater itself, replacing the corroded anode rod is easy and inexpensive to do while troubleshooting other problems.
In A Nutshell: RV Hot Water Heater Troubleshooting Tips:
- Make sure the water heater bypass vales are open.
- If you have an outdoor shower, make sure both hot and cold knobs are completely turned off!
- Ensure that your propane tank is full. Low or empty tanks can prohibit flow.
- If there is water dripping from the RV water heater access panel, the temperature may be set too high.
- If you have an electric water heater, consider replacing the heating element.
- Test that the water heater thermostat works using a multimeter.
- Do you have low water pressure? Make sure you are only using one faucet at a time. Use a high-quality water pump. Replace the water heater check valve.
- Get your circuit board tested at an RV service center.
- Check your fuses.
- Replace the water heater anode rod (if applicable).
Installing The Girard, Atwood, or Suburban Tankless Heater
Tankless hot water heaters like the Girard, Atwood, or Suburban are becoming more popular. These are easy to install and can replace your previously tanked system.
The most common reason your new water heater will not turn on is if there’s air in the gas line. You can remove the air by turning on the stovetop burner and letting it run for a few seconds.
Another reason the water may not come out hot is if the faucet or showerhead has too low of a flow rate. You may need to kick-start the water heater by turning faucets on full blast, bleeding air from the water lines, removing any water restrictors, and running just one water appliance at a time.
That’s A Wrap!
Broken water heaters are a common problem in the RV world. Fortunately, many of these issues can be easily fixed. Remember to check your owner’s manual for a brand-specific troubleshooting guide.