Rheem Water Heater Gas Valve Problem

Rheem Water Heater Gas Valve Problem: Here’s What To Do

This guide on the Rheem Water Heater Gas Valve Problem will describe:  

  • How do you tell if the water heater gas valve is bad?
  • How do you replace the gas valve on a Rheem water heater?
  • How much does it cost to replace a gas valve on Rheem Water Heater?
  • How do you reset the Rheem water heater gas valve?
  • What causes the Rheem Gas Water Heater to produce insufficient hot water?

Without further ado, let’s dive in.

How Do You Tell If Rheem Water Heater Gas Valve Is At Problem? 

A bad gas valve on the Rheem water heater prevents the pilot light from coming on. Or, the pilot light won’t stay lit once you release the igniter button if the gas valve is at fault. Besides, it may cause the water to be too hot or trip the thermal cut-off switch if the gas valve goes bad. 

Sign of a faulty gas control valve thermostat

Of course, those problems are also the symptoms of a defective thermocouple. So, it’s better to test the thermocouple first before swapping the old gas valve. To test the thermocouple electrically, you should use a multimeter. 

Once you get the multimeter, just disconnect the thermopile wire harness from the gas control valve. Then, attach the red lead of the multimeter to the red terminal of the thermopile and the black one to the white terminal. 

Now, set the gas control to pilot and hold down the gas control knob. Then, keep depressing the igniter button at the same time. You can check out this video if you don’t know how to test the thermopile: 

A functional thermopile should give between 650 to 850 millivolts. If you don’t get the reading, you must replace the thermopile. 

If there is no issue with the thermopile and the pilot light goes out, I bet the gas valve is the culprit. 

In this case, you must replace it to solve the Rheem water heater gas valve problem. The next chapter will help you change the gas control valve. 

Rheem Water Heater Gas Valve Replacement: The How-To Steps

Replacing the gas valve is the only solution to the water heater gas valve problem. It’s because there is no option to repair the gas valve. And this chapter will let you learn how to replace gas control valve on Rheem water heater. It will save you hundreds of bucks. 

Before heading over to the replacement workflow, ensure you have the following equipment at your fingertips: 

  • An adjustable wrench
  • A pipe wrench
  • A garden hose
  • A new gas valve

Step 1. Turn the Gas Supply Off

Begin with turning the gas shut-off valve to the Off position. It will stop the gas from flowing into your water heater. Just turn the valve that is in the gas line so that it will stay perpendicular with the gas supply line just like this: 

set the handle perpendicular to the pipe

Step 2. Drain The Water Tank

Attaching a garden hose

Attach a garden hose to the bottom of your water heater and place the other end of the hose to the nearest floor drain. Ensure you close the shut-off valve at the cold water inlet line. Now, open the drain valve of your water heater and let the water drain. 

Step 3. Disconnect all the lines from the Gas Valve

Disconnecting the lines from gas valve
*Disconnecting the lines from gas valve*

Use the adjustable wrench to detach all the lines like the thermocouple connector and other supply lines. The gas valve is connected to the gas line through a pipe. You need to disconnect the pipe by unscrewing the nipples on both sides of the tee. Then, detach the gas line from the gas valve. Don’t forget to store the nipples and other pieces as you need them. 

Step 4. Replace The Gas Valve

Once you unhook all the lines from the gas valve, it’s time to remove the valve from the unit. Just grab a pipe wrench, adjust its jaws, and set the pipe wrench on the gas valve. Then, rotate the pipe wrench counterclockwise to pull out the gas control valve. 

Now, install a new gas control valve. Before installing, use Teflon tape on the threaded part of the pipe leading to the hot water. Use the pipe wrench again to tighten up the gas valve. 

How Much Does It Cost To Replace A Gas Valve On a Rheem Water Heater?

The average cost of replacing your water heater gas valve is between $150 and $550. It includes the labor cost of $50 to $250. The price range of the replacement part is between $100 and $300. 

Criteria that will vary the cost of replacing a gas valve are the type of valve, water heater size, and the complexity of the installation. On the other hand, if you DIY the replacement task, it will cost you only the price of the gas valve.

How Do You Reset Rheem Water Heater Gas Valve? 

Resetting a gas valve on a Rheem water heater is not rocket science. Just follow the below steps to reset it:

  • Turn the valve off and unplug it from the electrical connection for a minute.
  • Plug it back again and turn the valve on. 
  • Now, set the temperature knob to the lowest setting. Now, rotate the knob from the lowest setting to the highest setting. Count 1, 2, 3, 4, 5, 6, and 7 and rotate the knob back and forth at the same time. Once you reach 7, you can see the status light stops flashing, which indicates you reset the gas valve successfully. 

What Causes the Rheem Gas Water Heater To Produce Insufficient Hot Water?

Your Rheem Gas Water Heater will produce insufficient or no hot water due to one of the following reasons: 

  • Your hot water demands exceed the capacity of the water heater. To avoid this problem, wait several minutes to let the unit recover from an abnormal demand. 
  • The inlet gas pressure should be between 4″ WC and 10.5″ WC for proper functioning of the unit. If the gas pressure is low, the water heater will heat the water insufficiently. Adjust the gas pressure to meet the requirements set by the manufacturer to resolve this issue. 
  • When you set the gas control thermostat to a lower setting, you will get the hot water according to the input. Turn the combination gas control to a higher setting to fix the low-temperature issue. 
  • If the hot water faucets remain open, you will get inadequate hot water. Ensure you close all the hot water faucets. 


Can a gas control valve be fixed?

No, a gas control valve can’t be fixed. It means you need to replace the gas valve once it gets faulty. 

Can you change a gas valve on a water heater without draining it?

No, you can’t change a gas valve on a water heater without draining it. Just attach a garden hose to the drain valve which you can find at the bottom of the water heater. Then, place the other end of the hose to the closest floor drain. Now, open the drain valve and drain the water. 

How long should a gas valve last? 

A gas valve should last up to 15 years. 

Read Also:


You must replace the gas valve if the Rheem water heater gas valve is at fault. Fortunately, we broke down the way of changing it. Just follow the steps we mentioned and make the replacement. 

If you have any questions about the water heater, leave a comment below. We feel happy to help.  

Similar Posts


  1. If my Rheem water heater gas valve is faulty while tank is still under warranty, will Rheem pay to have it replaced, including part and labor?

  2. I have a gas 40 gallon Richmond water tank made by Rheem. I’m very upset Rheem caps off their labor price at $150.00. This leaves too much leeway for a job that can cost far more than that. My last water heater was taken care of with not just with parts but the labor. And why can’t the problem be accessed before sending the gas valve. Very strange that a 2 year old water heater should have a faulty gas valve. I will check the warranties carefully before buying this brand again as I’m on a fixed income. What good is the part if I don’t have enough money to pay the serviceman.

    1. Sorry to hear that my friend…

      We are going through a terrible situation- first the pandemic and second, the war. The best thing we can do is to adapt with the situation though it’s difficult.

      I recommend you to have the gas valve replaced by yourself, which will save you the labor cost.

      Best of luck!

  3. I am afraid to replace it by myself for injury to my family me or my house I am surprised and very angry I fill cheated with a limited warranty if I had known I’d go through this I would have never bought this faulty water heater I am surprised they don’t have another recall

    1. Hey Lucille,

      Yes, it’s hazardous to perform such replacement task that involves gas. I recommend you to call a certified plumber to make that replacement for you. Feel sorry for the experience you have with Rheem.

  4. I bought propane water heater installed it but the pilot would stay lite, I replaced the theme coupler same problem,if I only had a few gallon in the tank not all the way to the gas valve can that cause the pilot to go out? Or do I need a new gas valve?

    1. Insufficient fuel in the gas tank can also cause the pilot light to go off. I recommend you check gas tank and ensure there is enough amount of gas. If refueling the tank with gas doesn’t improve the condition, inspect the gas valve. If needed, replace the gas valve with a new one. However, I highly recommend you to call a certified plumber to check your water heater.

Leave a Reply

Your email address will not be published. Required fields are marked *