Suburban Water Heater Won’t Stay Lit [11 Easy Fixes]

Your Suburban water heater won’t stay lit? Well, that can be because of several reasons such as a bad thermocouple, faulty control board, jammed flue, the air in the gas line, low gas pressure and defective igniter.

Plus a tripped high-limit switch, a defective thermostat, a malfunctioning heating element, a damaged pilot assembly, and a blocked burner orifice are also responsible for your heater keeps shutting off.

Keep reading our Suburban water heater troubleshooting guide to fix yours ASAP.

Table Of Contents

Suburban Water Heater Won’t Stay Lit [11 Easy Fixes]

Now let’s take a deeper look at the causes behind Suburban water heaters not staying lit and their simple solutions.

1. Bad Thermocouple

A thermocouple is a device that detects the pilot flame which allows the gas valve to open up and then ignite the burners.

When your flame sensor is faulty, your heater’s pilot flame will go undetected and the gas valves will close up causing your heater to turn off.

A bad thermocouple is the most common cause of water heaters shutting off. Check this first.


You can test the thermocouple simply by pressing the control knob down on the PILOT position and holding on for a while.

If you see that the heater is lit when the control knob is pressed in but as soon as you release the knob it turns off that means the thermocouple is the issue. 

But in case after the release the heater still stays lit and doesn’t shut off immediately, the problem is probably another heater component.

The best way to deal with a defective Suburban water heater thermocouple is by replacing it.   

2. Faulty Control Board

Another possible cause for your heater to keep shutting off is a bad control board. This one is costly to fix in comparison but not uncommon. 


Call the manufacturers to ask them for a new control board or for help regarding which control board to buy.

You should hire a professional to assist you with the replacement of the Suburban water heater control board. 

3. Jammed Flue

The flue is the venting system through which the exhaust leaves the water heater. If your heater’s flue is jammed, it will trap all the heat from your heater.

This can overheat it and cause the heater to shut down for safety.


Locate the flue and check it for blockage. Here’s how you clean up the vents:

Step 1: Turn the gas water heater’s gas feed off. Continue to the following step once the pilot has turned off.

Step 2: Connect your vacuum cleaner to an extension cord. Check to determine if the vent hood above the heater can be removed. With the vacuum cleaner extension, you’ll be able to reach further into the vent.

Step 3: Place the vacuum hose and extension above the heater in the venting. Vacuum up whatever you can from that area.

Step 4: To reach portions of the vent that the extension hose can’t reach, use a duct cleaner. To remove all dust and pollen particles, rub the smooth end around the inside of the vent.

Step 5: Restore everything once cleaned. 

4. Air In Gas Line

Air in your gas line stops your pilot from lighting up properly. It can be why your water heater won’t stay lit.


Bleeding out the air from the gas line is the way to go. After turning off the water heater, locate the hose bib to bleed out air.

Place a bucket under the bib to protect the floor. Turn the hose clockwise to attach it to the bib. Drain out the water into your lawn.

After draining the tank till clean water starts coming out and there is no sputtering, you can stop.

5. Low Gas Pressure

The LP side of the Water Heater requires 11 Water Column Inches of propane pressure to function properly. You can’t inspect it without specialized equipment. 

You can use your RV Furnace as a stand-in for specialized equipment. For the furnace to work properly, it needs a steady supply of propane. Propane flow should be fine if the furnace is working properly.


To reset the overflow protection device, turn off the tank valve in use, wait a few seconds, and then carefully reopen it.

If it doesn’t work, try moving the auto-changeover regulator to the other LP tank and slowly opening the tank valve on that tank. 

If that doesn’t work, shift the LP tanks’ positions to avoid a faulty high-pressure pigtail or high-pressure regulator.

In case none of these steps solves the problem, and you still detect a propane flow issue, it’s possible that the auto-changeover regulator will need to be replaced.

6. Defective Igniter

A defective igniter fails to turn on the burners and your water heater won’t stay lit that way.

To know whether the igniter is the problem, check to see if the igniter produces sparks during ignition trials. In case you can’t spot sparks, your igniter is most likely faulty.


Replacing the igniter will fix the issue and your heater should be running normally. If you aren’t feeling confident enough to replace the igniter on your own, it is better to enlist professional help. Better safe than sorry.

7. Tripped High Limit Switch

The high-limit switch is installed in your heater for safety purposes. Water heater overheating has caused explosive accidents in the past.

So, modern water heaters feature a high-limit switch that shuts off the water heater when it surpasses a pre-specified temperature. Thus, a tripped switch can cause your heater to shut off.


Resetting the high-limit switch should fix the issue. But if the high-limit switch trips again after you start up the heater, the switch is probably defective and needs replacement. 

8. Defective Thermostat

A malfunctioning thermostat can cause the water heater to shut down. The problem could also be with the wiring of the thermostat. 


First, check the wiring of the thermostat. Check the owner’s manual for the wiring diagram. Repair any damaged wires and tighten any that are loose.

If that doesn’t fix your heater, test the thermostat with a multimeter to check whether it needs replacement. The following video should help you in the testing process.

9. Malfunctioning Heating Element

It may be time for a replacement coil, due to the age of the water heater. The coils are responsible for transferring heat from your tank to your home.

And if they become too cold or blocked with minerals like calcium, you will not have sufficient heating capability. This may be why your heater isn’t running continuously.


You need to replace the heating element. The process isn’t too complicated. In case you have some prior experience with heating appliances, you can try DIY replacing it. Watch the video below for help.

10. Damaged Pilot Assembly

If your heater’s pilot assembly is damaged, it can be why your Suburban RV water heater will not stay lit.


You need to check whether the pilot light is lit properly. If the flame keeps going out or not turning on at all, you probably need to replace the assembly. 

11. Blocked Burner Tube

Dust or calcium deposits could obstruct the burner orifice. It could prevent the burners from lighting properly. 


To get the water heater to work correctly again, you’ll need to replace the burner tube. Follow these instructions to change the tube on your own:

  • For around five minutes, turn off your hot water heater and turn on a nearby tap. Remove the water heater’s lower access panel.
  • Remove the old tube’s base from the gas valve to the pilot light by unscrewing and removing it. Replace the burner tube.
  • Using an adjustable wrench, reattach the base of the new burner tube to the gas valve for a snug fit.
  • Check to determine if the water heater is working properly by turning it on. If it still has issues, engage a mechanic to give it a complete examination.


How do I reset my Suburban water heater?

Look at the back of the heater. At the bottom there are two buttons. The electric circuit reset is on the left, while the LP reset is on the right. Press down on them to reset the water heater.

Why Is My RV water heater not heating the water?

A faulty thermostat, a broken or damaged dip tube that allows cold water to mingle with hot water at the top of the water heater, or low temperature setting on the thermostat can be why your heater isn’t producing enough hot water.

Should I leave my RV water heater on all the time?

It is safe to leave your electric RV water heater on at all times, whether you are stationary or traveling. Other drawbacks include cost and the influence of fuel use on the environment, although safety should not be an issue.

What happens when a heating element goes out in a water heater?

Without a working heating element, your water heater will be unable to heat up water. You will need to replace the heating element to restore your heater functions.

How much does it cost to replace a water heater element?

You can expect it to cost somewhere between $200 and $300 to replace your heating element. Usually, there are two heating coils in a water heater.


Hopefully, now you know the answer to the question, ‘ how do you fix a hot water heater that won’t stay lit?’.

In case you have any queries regarding your Suburban water heater you can leave us a comment. We will do our best to help you.

About David

David is a man who loves doing research and finding out the best solution to any type of heating appliance issues like heaters and fireplaces. Whenever he finds the perfect solutions to any issues of heating appliances after doing in-depth research, he loves to share them with his readers. In fact, his aim is to help his readers to fix the issues with their heating appliances easily.More about us .

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