Rheem Water Heater Red Light Flashing 7 Times [7 Easy Solutions]

Rheem water heater red light flashing is the error indication of the gas control valve failure of the heater. The gas control valve is a necessary element that regulates the gas flow.

If it fails, the unit doesn’t get enough fuel to heat the water, causing 7 flashing errors.

rheem water heater red light flashing 7 times

The root reasons for this issue include obstructed venting, blocked air intake, clogged or damaged burner parts, and blocked TRD. Also, a faulty thermocouple may be to blame, and even a defective gas valve itself is the culprit.

Anyway, before replacing the gas valve, we will reset the heater and will see if the issue is resolved by this. 

Follow the below guide to get complete instructions to fix the 7-time blinking on the Rheem water heater. 

Rheem Water Heater Red Light Flashing 7 Times [7 Easy Solutions]

Here are all the responsive factors for this issue with the well-proven solution steps: 

Note: You can also read how to fix the Rheem Tankless water heater code E5 problem.

1. Reset The Rheem Water Heater

If your Rheem water heater’s red light blinks 7 flashes indicating gas control valve failure, resetting the valve would be your first troubleshooting step. The gas valve is an essential device on the heater which regulates the flow of gas. 

Opening or closing the valve manages the gas flow to the heater. When the gas control button is pressed, the valve allows enough gas flow to ignite the pilot light which is a must to heat the water. 

Anyway, in the case of valve failure, the complete ignition system would be interrupted, which can be solved by resetting this device. 

If you are looking for how to reset a Rheem water heater gas valve, follow the below steps:

How To Reset Rheem Water Heater Gas Valve

  • To reset the gas valve on the Rheem water heater, move to the gas valve.
  • Set the pilot knob to the “OFF” position.
  • Leave the gas control valve in this position for about 5 minutes.
  • When the time is passed, set the control knob back to the ‘On’ position.
  • The gas valve will be reset, and the blinking error should be erased. Now set your desired temperature. 

2. Obstructed Venting

All the water heater features exhaust vents that are used to remove the byproducts of combustion from the heater. If the venting system is clogged by debris and specks of dirt, it will prove worse and extremely dangerous for the heater’s function. 

Once the vents are blocked, it triggers pilot light problems by creating a malfunction in the thermocouple. When the thermocouple gets a bad signal from the pilot light, it prevents the gas valve from working properly. So, this time, we need to concentrate on cleaning the exhaust vent. 

How To Clean The Venting On The Gas Water Heater

  • First, turn off the gas supply.
  • Move to the gas control valve and set the knob to the “OFF” position.
  • Then the pilot light will extinguish. 
  • Locate the exhaust vent from above the heater. 
  • Now, you need to disassemble the venting pipes to reach out the obstruction.
  • Or, you may use a vacuum hose. Insert it into the inside of the vent opening and vacuum up all the dirt.
  • Apart from this, a plumber’s snake will make the task easier. Just insert it into the vent pipe’s obstruction. When it hooks to the clog, pull the snake out.
  • To clean the around inside of the vents, take a duct cleaner and pick up all the dust and pollen particles.
  • That’s how you can easily unclog your heater vent. 

3. Broken Glass Vial Of Thermal Release Device Or TRD

In the Rheem hot water heater, there features a device in the combustion chamber named thermal Release Device (TRD). TRD is mainly a safety device that contains a gas vial filled with liquid. 

thermal release device or trd

When the heater’s temperature exceeds the safety limit, the device trip off by itself. Then the glass bulb breaks, allowing a spring-loaded metal damper rod to spring up and cutting off the air supply to the chamber. 

Then, the main burner will shut off and prevent the heater from any overheating damage. Now, if the vial has burst or broken, it affects the gas valve function causing 7-time blinking. 


  • Locate the thermal release device and remove it from the housing.
  • Grab the housing and rotate it about 90 degrees to remove the housing.
  • Now check if the glass vial is burst out or broken. If the TRD fails, the glass bulb ruptures and the spring starts to release.
  • You need to new glass vial for your Rheem water heater and replace the broken one.
  • Replace the broken vial of TRD with the new one.
  • Call a professional to precisely replace the defective TRD.

4. Clogged Burner Orifice

If still, your Rheem water heater’s red light is blinking 7 times, there is a higher chance of the clogged burner orifice. The gas burner is an essential element of the heater, which is attached to the thermocouple, main orifice, main gas supply tube, pilot burner, pilot orifice, and pilot burner gas supply. 

If the gas line, orifice, and burner gas ports are blocked by debris, it affects the complete ignition system. When the gas valve lets gas flow, it passes to the combustion chamber through the pilot and manifold tubes. 

In the case of the blocked burner assembly, the gas will not flow, the burner won’t fire up, and the status light will blink the error code 7.

How To Clean Rheem Water Heater Burner

Cleaning of a water heater burner should be done in sequence as we have described below:

 clean rheem water heater burner
  • First, turn off the heater and set the gas control valve to the OFF position. Also, close the gas shutoff valve
  • Disconnect the thermopile, temperature sensor, and igniter from the gas valve.
  • Now remove the inner door to access the burner assembly,
  • Gently slide the burner tube and assembly out from the combustion chamber
  • Now, start cleaning the burner assembly and its parts.
  • Take a wire brush or a soft bristle brush to clean the orifice for obstructions and clean the scale deposits and debris.
  • Unclog the combustion chamber and flame arrestor plate using a vacuum cleaner with a brush attachment or compressed air.
  • After cleaning, dry out the complete assembly.
  • Then slide the burner assembly back into the combustion chamber and reassemble the heater.

5. Blocked Air Intake

If the red light flashes 7 times, there would be a higher possibility of a blocked air intake screen. The air intake screen allows proper air circulation within the unit. 

If the air intake screen is blocked by lint buildup, the burner will not get enough gas, and the gas valve will stop working properly. For this, the burner will not remain lit for prolonged periods. For the gas valve malfunctioning, the red light will blink 7 times.

How To Clean Rheem Water Heater Air Intake

Turn off the heater and gas supply before starting cleaning. Then, locate the air intake screen of your water. You will find it at the base of the water tank on the front of the unit. Slide out the burner assembly to access the air intake screen.

cleaning the air intake screen using compressed air

Now take compressed air to suck up all the dirt and debris from the air intake screen. Run the compressed air back and forth across the air intake screen.

Then, remove excess dust buildup using a paper towel dampened with water. After cleaning, reassemble the heater and turn on the gas supply.

6. Faulty Thermocouple

A thermocouple is a sensor that generates a small electrical current when it’s heated by the pilot flame. This small current sends to the gas valve to keep the valve open and to continue the gas supply. 

faulty thermocouple

But if the thermocouple starts malfunctioning, it fails to sense the pilot light and generate the voltage necessary to keep the gas valve open.

Also, if the thermocouple is accumulated dirt particles or is kinked, it interrupts the signal sensing. Only replacing the thermocouple can resolve this error blinking.

How To Fix A Bad Thermocouple On A Water Heater

  • First, locate the thermocouple at the water heater’s burner assembly and right in front of the pilot light.
  • Look for carbon build-up on the thermocouple. Clean the thermocouple using emery cloth sandpaper. 
  • Then check the thermocouple electrically. For this, you need to measure the voltage reading of this device using a multimeter.
  • A healthy thermocouple will give a voltage reading between 20 and 30 millivolts.
  • If the reading is below 20 millivolts, be sure the thermocouple is defective.
  • Once you’ve determined that your thermocouple is at fault, replace the defective one with the help of any certified plumber. 

7. Replace The Defective Gas Control Valve

If all the above troubleshoots have failed to prove well, and the red light is still blinking 7 times, a faulty gas valve could be the problem. There are several for why the gas valve may stop working. 

replace the defective gas control valve

Here the valve itself may have simply worn out or damaged. Sometimes, the gas valve stops functioning due to basement seepage or submersion. Other possible reasons include a glitch in the safety circuit or defection in electronic gas ignition components.


Whatever the reason is, you need to replace the faulty gas control valve. After replacing the valve, the 7 error blinking will be erased, and the heater will start function gain. 

You can do it by yourself, or it will be better to contact any plumber to replace the faulty gas valve. But below, we have discussed some basic steps to replace the defective gas valve from your Rheem water heater. 

How To Replace Faulty Gas Control Valve On Rheem Water Heater

Here are the instructions to replace the defective control valve:

  • First, turn off the heater and shut off the gas shut-off valve.
  • Turn off the water supply and drain the water from the tank. For this, open the drain valve.
  • You will need a wrench to disconnect the gas supply line from the gas valve.
  • Disconnect the valve adapter and burner assembly.
  • Unplug all the connections from the valve.
  • Disconnect the bad gas control valve using a wrench
  • Install the new gas control valve and connect all the necessary attachments.
  • Connect the gas line with the control valve.
  • Turn on your heater and open the gas supply.
  • Light the pilot light. 
  • The Rheem water heater blinking 7 times will be resolved.


What is a flammable vapor sensor lockout on a water heater?

Flammable vapor sensors are safety devices on the heater. They go to soft lockout when the flammable vapors are detected. Thus, the chance of ignition of the vapors is reduced.

Why won’t the Rheem water heater turn on?

The water heater will not turn on when it is not getting enough power. Also, tripped limit switch, failed heating elements, the air in the gas line, or a defective gas valve are also culprits. 

Wrapping Words

Throughout this article, we have explored each of the aspects that are responsible for the 7-time error blinking in your Rheem unit. Also, our assembled solutions procedures will assist you in fixing the error more effectively and within a short span of time.

 Hopefully, you are now clear on how you will erase the red light error from your unit. But still, if you have any questions left behind, let us know through comments. We will be happy to help you. 

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.

3 thoughts on “Rheem Water Heater Red Light Flashing 7 Times [7 Easy Solutions]”

  1. My 6 year Rheem water heater valve flashes 7 times red and will not light the pilot. Heater was off for 8 days prior. Can you help please?
    Thank you Octavian

    • Hi Octavian

      Generally, when the gas control valve fails, the water heater doesn’t get enough fuel to heat the water, causing 7 flashing errors.

      Well, the root reasons for this issue include obstructed venting, blocked air intake, clogged or damaged burner parts, and blocked TRD. Also, a faulty thermocouple may be to blame, and even a defective gas valve itself is the culprit.

      However, before replacing the gas valve, we need to reset the heater to see if the issue is resolved by this.

      If resetting doesn’t work, inspect all the above-mentioned issues & try to find out the main culprit behind the problem.

      Then, fix it following our solution guide in the article.

      Hopefully, your water heater problem will be solved.

      Best of luck!

  2. My 5 year year old Rheem gas hot water heater flashed 7 times on at least 5 occasions over the 5 years. It always “fixed itself” by just resetting. Turn OFF, wait a few minutes. Then go through the Pilot lighting sequence.


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