LEARN and EARN!

Get your RV Technician Certification in as little as 5 weeks!

Fix Your RV Water Heater FAST with These 5 Easy fixes

May 6, 2025
/
Tony Flammia
Image

Imagine this: youโ€™ve been driving all day, finally pull into your campsite, get everything set up, and all you’re dreaming about is a long, hot shower. But when you turn on the tapโ€ฆ ice-cold water. ๐Ÿ˜ฉ

Before you panicโ€”or call a technicianโ€”there are five quick and easy things you can check yourself that just might get your hot water flowing again. I’m Sue Rasmusen, instructor at the National RV Training Academy (NRVTA), and today Iโ€™m walking you through five common water heater issues that are easy for any RV owner to troubleshoot.

Letโ€™s get started! ๐Ÿ”ง


1. ๐Ÿ’ง Lukewarm Water? Check for a Bypass Valve Issue

If youโ€™re getting lukewarm water instead of hot, your water heater might not actually be the problem. The issue could be a bypass valve that wasn’t reset properly.

There are two common bypass points:

  • At the back of the water heater โ€“ This often happens after dewinterizing. If you forgot to close the bypass, cold and hot water can mix, reducing temperature.
  • At the shower โ€“ Sometimes internal shower bypasses remain open, leading to the same result.

โœ… Fix: Make sure all bypass valves are properly closed after winterization or maintenance.


2. ๐Ÿ”ฅ No Heat on Propane? Check the Tank

Trying to run your water heater on gas, but getting nothing? Listen closely. If you hear a repetitive โ€œclick, tick, tick,โ€ sound but no ignition, thatโ€™s a sign your propane may be the culprit.

โœ… Fix:

  • Make sure your propane tank is full.
  • Ensure the valve is open.
  • Confirm that propane is reaching the appliance.

Sometimes the simplest answers are the right ones!


3. โšก Using Electric Mode? Donโ€™t Miss the Hidden Switch

Many RVers donโ€™t know this, but if you have a Suburban water heater, thereโ€™s a hidden electric switch on the heater’s exterior face. If that switch is off, your water heater wonโ€™t work on electricityโ€”no matter what your inside panel says.

โœ… Fix:

  • Locate the manual switch on the outside of the Suburban water heater.
  • Flip it to โ€œonโ€ and try heating again.

This fix is incredibly commonโ€”Sue sees it all the time!


4. ๐Ÿ”Œ Water Heater Not Powering On? Check the Fuse

If your water heater isnโ€™t making any noiseโ€”no clicks, no ignition attemptsโ€”check the fuse box inside your RV.

Water heaters typically use a 15-amp fuse, and if itโ€™s blown, the whole system may be dead silent.

โœ… Fix:

  • Check the fuse panel.
  • Replace the blown fuse with a new 15A fuse.
  • Use a multimeter to test if youโ€™re unsure.

This is a super quick and affordable fix that could save your trip.


5. ๐Ÿงฏ Got a Dometic Water Heater? Test the Thermal Cutoff

On Dometic units, there’s a small but mighty component called a thermal cutoff on the front of the heater. If this safety feature blows, neither electric nor gas modes will work.

โœ… Fix:

  • Use a multimeter set to ohms.
  • Check the thermal cutoff for continuity (a complete electrical path).
  • If it fails the test, simply swap it out with a replacement part.

Replacing a thermal cutoff is fast, easy, and could be the difference between cold showers and comfort.


๐Ÿšฟ Get That Hot Shower Back!

There you have itโ€”five easy fixes for your RV water heater that anyone can do with basic tools and a little know-how. Donโ€™t let cold water ruin your evening after a long travel day.

Recap:

  1. Check water heater and shower bypass valves.
  2. Ensure propane is on and available.
  3. Flip the hidden Suburban switch.
  4. Check and replace blown fuses.
  5. Test and replace the thermal cutoff (for Dometic units).

Still having issues? Thatโ€™s when itโ€™s time to call in a certified RV technicianโ€”or consider training with us at NRVTA to learn how to handle it all yourself.

๐Ÿ‘‰ Subscribe to our YouTube Channel for more weekly Tech Tip Tuesdays.
๐Ÿ‘‰ Visit NRVTA.com to learn about hands-on RV training and certification.

Until next timeโ€”stay smart, stay safe, and enjoy the open road!

Fix Your RV Water Heater FAST with These 5 Easy fixes

Get Registered Today!

Talk to a student advisor to learn more!