White Rodgers Water Heater Thermostat Troubleshooting [Solved]

When your water heater isn’t producing hot water, chances are there is something wrong with the thermostat. Read our White Rodgers water heater thermostat troubleshooting guide and you’ll be able to fix your thermostat ASAP.

white rodgers water heater thermostat troubleshooting

White Rodgers Water Heater Thermostat Troubleshooting Guide

First, you’ll need to ensure that the thermostat indeed is the problem. For that, you can test the thermostat with a multimeter. Then you may need to install a new thermostat by taking off the old one.

So let’s dive right into our White Rodgers hot water heater thermostat troubleshooting guide.

How To Test White Rodgers Water Heater Thermostat With A Multimeter?

All you need is a multimeter, a Philips flathead screwdriver, a nut driver, and tape to test the thermostat. It’s an easy process. You should be able to do it yourself. Here are the steps!

Step 1: Locate the water heater breaker panel on your circuit breaker panel and switch off the water heater or hot water.

Step 2: Remove the top and lower thermostat access panels with a flathead screwdriver or 1/4-inch nut driver from the unit’s side.

Step 3: You have the option of removing the insulation completely or folding it over the thermostat. Remove the plastic safety guard that has been placed over the thermostat and heating element.

Tape the insulator in place as well, and try not to pull the wiring out while working on this step.

Step 4: Check to see if the red reset button for the high limit has tripped. This red button is the White Rodgers water heater thermostat reset button. If it has tripped, hit the button.

If the heating components fail, the connections on the thermostat have fused closed, or the thermostat is out of calibration, the red switch button may trip.

Step 5: Disconnect the wires entering each terminal with your Philips screwdriver. Set the upper thermostat to the highest setting, and the scale on your multimeter to the RX1 setting.

Step 6: Set your analog or digital meter to 200 ohms, which is the lowest resistance. A click should be audible. Then, on the left side screw terminal, place the black probe. Also, on the left side, place the other red probe on the opposite terminal.

Then use your reading to double-check the thermostat’s operation. Your thermostat is working properly if the meter displays zero or a value extremely close to zero. If it reads wide, though, you may have a faulty thermostat.

Step 7: Place the probes on the screw terminals and lower the upper thermostat on the right side to its lowest setting. In addition, this should return a zero value.

After you’ve verified that the higher thermostat is working properly, repeat the process with the lower thermostat. The lower thermostat has only two terminals, so keep that in mind. Check to see if the reading is zero. 

You can test your heating elements if you’re confident the thermostats are in good working order. However, if one or more of the thermostats needs to be replaced, continue reading.

How To Replace Thermostat?

The thermostat can be replaced easily if you follow the given steps. We don’t recommend you try doing this yourself if you don’t have that much electrical knowledge.

Step 1: Disconnect the power cord. Close the water intake valve and turn off the gas supply. Then, using a flathead screwdriver, open the drain valve and remove all of the water from the tank.

Step 2: Be advised that after emptying the water from the tank, you should open a hot water faucet in the house to help release the water from the tank. Close the valve and unthread the gas pipe union with a pipe wrench to separate the pipe.

Step 3: Remove the T connector pipe’s top and lower pipes next. The T connecting line from the control valve can now be threaded.

Step 4: Disconnect the igniter and sensor wire harness as well as the blower assembly wire harness. Unthread the nuts connecting the burner tube to the control valve with a three-quarter-inch wrench. Rotate the old control valve counterclockwise to unthread it. A half-inch pipe can be inserted into the gas inlet port to aid with valve rotation.

Step 5: The replacement control valve is now ready to be installed. Tighten the new valve by threading it clockwise into the tank. Apply sealant to the T connection pipe’s threads before threading it into the new control valve and tightening it.

Step 6: Rethread the upper and lower pipes after applying sealant. Depending on your water heater model, you may need to replace the burner orifice.

Realign the main gas supply line and rethread the union to secure it. To do so, remove the burner access cover and use a three-eighths-inch socket to unscrew the burner cover’s mounting nuts.

Step 7: Pull the burner component loose by removing the vapor sensor and bracket from the tank base. Unthread the screws holding the burner head to the tube with a Phillips head screwdriver.

Step 8: Pull the burner head free with care. Rotate the old burner orifice counterclockwise with a three-eighths-inch wrench to help unthread it from the tube. Determine which burner orifice is right for your model by consulting the instruction leaflet. After that, thread the new orifice onto the tube and tighten it.

Step 9: To secure the burner head, re-align it, then thread and tighten the screws. As you slide the burner assembly into the tank, make sure the burner tube is aligned with the support bracket.

Step 10: To secure the nuts, thread them and tighten them. On the tank base, snap the vapor sensor bracket into position. Connect the two-wire harnesses to the new control valve to complete the installation.

Step 11: Thread and tighten the knot to secure the burner to the valve. Replace the covered access. Allow the tank to refill by opening the water input valve. Then re-connect the power wire and switch on the gas supply.

Make that the reassembled gas pipes are free of leaks. Then set the desired temperature on the new control valve, and your water heater should be ready to use.


How does a gas water heater thermostat work?

The thermostat is a thermistor that produces a modest electric current in response to heat. When the temperature of the water rises, the current rises, and when the temperature falls, the current falls. Gas control turns on and off in response to changes in electric current. 

Does a gas water heater have a heating element?

No, it doesn’t. A gas heater appears similar to an electric heater, however, it lacks the two heating elements. It has a gas burner at the bottom and a chimney that runs up the center of the tank.

Are gas water heater thermostats universal?

No, all gas water heater thermostats aren’t universal. Between single-element and dual-element water heaters, there are some differences in thermostats. There is also a difference between the upper and lower thermostats in dual-element water heaters.

What should my hot water tank thermostat be set at?

The temperature is 120 degrees Fahrenheit. This is the default thermostat temperature in most new water heaters, and it’s the U.S. Department of Energy’s suggested setting. Hazardous microorganisms, such as those that cause Legionnaires’ disease, are prevented from proliferating and may be killed at this temperature.

What does the lower thermostat do on a water heater?

The lower thermostat detects a heat change as the cold water enters the bottom of the tank. The incoming cold water will be heated by the bottom heating element. When all of the hot water in the tank is used, the higher thermostat will demand heat and draw electricity from the tank’s bottom.


Now you know what to do when you’re wondering “How do tell if my water heater thermostat is bad?”. Hopefully, our White Rodgers water heater thermostat troubleshooting guide helps you to get your heater running ASAP. 

Note: You can also read how to add a thermostat to a gas fireplace.

About William

William is the founder of Fireplacehubs.com. He has real life practical skills in fixing smoker & heating appliance issues. He loves to share his knowledge & helps others in fixing their appliances & saving their money. William firmly believes that anyone can repair his or her unit with the correct guidance & knowledge. See more at about us.

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