RV Water Heater Troubleshooting and Repair

by | Sep 16, 2023

RV Water Heater Troubleshooting and Repair

We started the day with no hot water when connected to the campground power and using the 120V power option for the water heater. Fortunately, we were able to use the propane switch and the water heater functioned well. For most RV water heaters, the parts that are most likely to fail are easy to test and replace if needed. This held true for our 12 Gallon Suburban Advantage Tank Water Heater model 5146A/F. Now it was time for RV water heater troubleshooting and repair.

Troubleshooting An RV Water Heater

We’ve all forgot to turn on the water heater when we arrive at the campground. This was the most obvious starting point. I checked to ensure both the 120V water heater switch was on and the breaker feeding the water heater had not tripped. Both were on and still no hot water.  Next step was troubleshooting the water heater components.

The components mostly likely to fail are the 120V water heater element or the thermostat switch. Starting with the water heater element, first ensure no AC or DC power is going the water heater. If the unit has been heating with propane, give the water heater time to cool.

testing rv water heater elementWe removed the heating element cover and use a digital voltmeter set to AC voltage to ensure no AC power is going to the heater element. Once confirmed, I removed one power lead from the electric heater element, set the digital meter to OHMS, and placed the probes on each heater element. We had a reading of 10 OHMS indicating a functional heater element.

Our next step was to test the 120 volt thermostat switch. On the 12 Gallon Suburban Advantage Tank Water Heater model 5146A/F there are two thermostat switches. This can be found near the top of the water heater with two rubber inserts used to reset the switches if overheating occurs. With the cover removed you’ll find the 12V thermostat switch on the right and the 120V on the left. The 12V has a wide, flat conductor running top to bottom and the 120V has a thin wire located in the same place.

testing rv water heater thermostat switchFirst we found the power wire located at the bottom of the 120V thermostat switch had overheated and some of the insulation wire was burned. We removed the wire and tested the switch with the digital voltmeter. The bottom of the switch has two tabs, one where the power wire connects and the second with a soldered wire going to the top of the switch. I set the digital volt meter to OHMS and placed a lead on each post. A working switch will read a short, zero on the digital voltmeter. If the switch has failed, the reading will be low or open depending on the voltmeter’s display. Our reading was low indicating a bad switch.

It was time to order parts and begin the repair.

Repairing An RV Water Heater

suburban 232306 thermostat switch model 232306We ordered a new Suburban 232306 Thermostat Switch, Model: 232306 from Amazon. Looking at the back of the thermostat switch ensure you see the 2306 before ordering. Replacing the switch was simple, slip off the power wires, remove the center nut, pull off the old thermostat switch and reverse the process to install the new unit. Make sure the nut is tight to create a thermal bond between the water tank and the switch, but do not over tighten and risk breaking the threaded stud from the tank.

We also suspect the power wire either rubbed the metal edge and the wire shorted, or the power connector wasn’t tight causing overheating, but most likely the thermostat switch overheated causing the wire to burn before the switch completely failed. We replaced the connector, reconnected all wires, replaced all the covers, and it was time to turn on the 120V switch to the water heater and see if our repairs worked.

RV Water Heater Troubleshooting And Repair Results

Our RV water heater troubleshooting and repair was a success. Turning the 120V power to the water heater and waiting about an hour, hot water had returned. The troubleshooting process discussed took less than 30 minutes. With Amazon Prime, we had the Suburban 232306 Thermostat Switch, Model: 232306 in two days and the repairs took less than an hour.

If you have basic skills using small tools, RV water heater troubleshooting and repair is simple. The two most common parts to fail are inexpensive. At the time of this blog, the Suburban 232306 Thermostat Switch, Model: 232306 was $16 and if the heating element failed, its cost would have been $20. With a few minutes of troubleshooting and repair we were able to have 120V heated water again.

If using tools and wiring isn’t your skill set and a RV technician is needed, this is one of the lessor cost repairs for parts with labor being the higher cost component.

The video below shows our step-by-step process to troubleshoot and repair. I’ve also included helpful links below for parts, tools, and our blog showing how to use a digital voltmeter.

rv water heater troubleshooting and repair
Helpful Links:
How To Use A Digital Voltmeter

Crenova MS8233D Digital Multimeter

Klein Tools 32500 11-in-1 Screwdriver

Suburban 232306 Thermostat Switch, Model: 232306

520900 RV Water Heater Element For Suburban RV SW Series Electric Water HeaterRV AccessoriesCheck out our RV Accessories page where we have listed a wide range of products from essential items to those “nice to have” RV products to make RV life more enjoyable. Every item listed is being used or has been used by Joan and I as we’ve traveled across the country in our RV.

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