Why Is My Rheem Water Heater Status Light Blinking Blue?

Rheem Water Heater Status Light Blinking Blue indicates a faulty or a proper functioning unit- depending on your water heater model. For example, if you have a power vent model from Rheem, the blinking blue status light implies a problem. 

On the other hand, a flashing blue light (every three seconds) will indicate that your water heater is operating like a champ if you have a Rheem Performance Plus Series Water Heater. 

Today, I will describe what the blue light on the Gas Valve LED indicates on the Rheem Power Vent Water Heater. So, let’s dive in. 

What Does Status Light Blinking Blue Mean On Rheem Water Heater?

On the Rheem Power Vent Water Heater, the status light will blink blue if the pilot light is off and there is a system problem. The number of blue flashes on the status light will imply the exact problem. 

For example, three consecutive blue flashes indicate that the pressure switch failed to open. It can also mean flammable vapor sensor lockout if the status light blinks blue seven (7) times. 

The following table will list all the blinking blue light codes and what problems they point to: 

LED Status	Problem
One flash every three seconds	Low flame signal
Two flashes every three seconds	Pressure switch failed closed
Three flashes every three seconds	Pressure and/or blower thermal switch failed open
Four flashes every three seconds	TCO activated
Five flashes every three seconds	Flame out of sequence
Six flashes of one, every three seconds	Failed trial for ignitions
Six flashes of four, every three seconds	Flame sense out of sequence
Seven flashes every three seconds	Flammable vapor sensor lockout
Eight flashes of two, every three seconds	Temperature sensor fault detected
Eight flashes of four, every three seconds	Combination gas control (thermostat) fault detected

Related: Rheem Water Heater Blinking Red Light

What Does Cause The Status Light to Blink Blue On Rheem Water Heater?

Low flame signal, flammable vapor sensor lockout, and defective gas control are responsible for the status light to blink blue.  

Low Flame Signal

One blinking blue flash on the status light will indicate a low flame signal. And a low flame signal on your power vent water heater will be a result of: 

• Too low gas pressure
• Low voltage to the water heater
• Defective pilot assembly 

How To Fix: 

First, measure the inlet gas pressure. The inlet gas pressure to your water heater shouldn’t exceed 10.5″ WC for natural gas or 13.5″ WC for LP gas. 

Second, connect the water heater with the provided power cord to a 120V, 50/60 Hz power supply. 

Third, replace the pilot assembly if the pilot light won’t come on when attempting to ignite the burner. 

Pressure Switch Failed Closed

The status light will blink blue two (2) times when the pressure switch fails to close. You will experience this water heater issue because of: 

• Incorrect blower pressure switch wiring
• The wiring to the blower pressure switch may come loose
• Defective blower assembly

How To Fix: 

To resolve this problem, verify that you wire the blower pressure switch according to the user manual. Next, ensure that the wiring to the blower pressure switch is correct and secure. 

If the mentioned remedy doesn’t bring any luck, I bet the blower assembly is at fault. Regarding this, you should replace the blower assembly. 

Open Draft Pressure Switch

Rheem Water Heater that flashes three (3) times may indicate an open draft pressure switch. Due to one of the following reasons, the status light will blink blue three times: 

• The wiring to the blower pressure switch and thermal switch is incorrect
• The wiring to the blower pressure switch and the thermal switch is connected improperly
• The vent system gets clogged

You can try the following troubleshooting steps to resolve this water heater problem: 

• Verify that the wiring to the blower pressure switch and thermal switch is correct and secure.
• Inspect the vent system for obstructions. Release the blockage from the exhaust vent if required. 

TCO Gets Activated

A four consecutive flash on the status light will indicate that the TCO or thermal cut-off switch gets tripped. 

Rheem Power Vent Water Heater has a safety feature called a thermal cut-off switch. When it senses excessive chamber temperature due to flammable vapors, the TCO switch will cut off the gas supply to the burner. 

As a result, the pilot light won’t stay lit and shut off the unit to protect you against overheating. 

How To Fix: 

Try to reset the TCO first as a remedy. If resetting the thermal cut-off switch doesn’t bring any luck, perform the continuity test to determine if it’s at fault. 

Replace the TCO if it fails the continuity test. I recommend you watch the following tutorial to learn how to test and replace the TCO: 

Flame Out Of Sequence

When the flame goes out of sequence, the status light will blink blue five (5) times. It actually occurs due to a defective combination gas control (thermostat). 

The only solution to this issue is to replace the combination gas control thermostat. I highly suggest you call your local plumber to replace the gas control. The following tutorial will help you learn how to make that replacement:

Failed Trial For Ignitions

When the unit conducts several failed trials for ignition, but the pilot won’t stay lit, the status light will blink blue (six flashes of one). 

Typically, you will encounter this issue with your water heater due to one of the following reasons: 

• The gas supply is off, or the gas pressure is too low
• Defective pilot assembly
• Faulty combination gas control (thermostat)

How To Fix: 

You can fix this problem by taking the following troubleshooting steps: 

• Turn on the gas supply to your water heater and verify that you turn on the gas valve fully. Also, ensure the inlet gas pressure is within specification. 
• Replace the pilot assembly.
• Replace the combination gas control (thermostat).

Flammable Vapor Sensor Lockout

The status light will blink seven (7) times when the flammable vapor sensor detects flammable vapors or gasoline. 

In order to fix this problem, verify that no flammable vapors or gasoline are present. Besides, you can reset the combination gas control (thermostat) to deactivate the lockout condition. 

Nonetheless, you can replace the flammable vapor sensor if the sensor looks fragile or damaged. 

Read Further: Honeywell Water Heater 7 Flashes Reset

Temperature Sensor Fault Detected

Eight (8) consecutive flashes of two on the status light indicate that the unit detects a temperature sensor fault. It happens if there is a loose wire connection between the gas control and the thermal well. Besides, a faulty thermal well of the gas control will cause the status light to blink blue eight (8) times. 

How To Fix: 

First, check the wire connection between the gas control and the thermal well. If required, tighten the wire connection. Next, ensure that the thermal well is working. Otherwise, replace the thermal well with a new one. 

Combination Gas Control Fault Detected

When the combination gas control is at fault, your water heater will notify you by blinking a blue light eight (8) flashes of four. The only way you can fix this issue is to replace the gas control. Besides, you can cycle power to the combination gas control to bring the unit back into working condition. 

What Does Stop Your Rheem Water Heater To Produce Hot Water?

If you get insufficient or no hot water from your Rheem Power Vent Water Heater, do the following: 

• Water usage may exceed the capacity of the unit. I recommend you leave the water heater for a moment to let it recover after an abnormal demand.

• Low gas pressure can prevent the unit from producing hot water. Verify that the gas supply is on and the inlet gas pressure doesn’t exceed 10.5″ WC for natural gas. 

• You may set the combination gas control (thermostat) too high. I recommend you set it to a lower setting like ‘HOT’ or A temperature settings. 

• Ensure that you close all the hot water faucets. Otherwise, the water heater will fail to produce hot water.

• Check valve error codes. I already described those error codes and the way you can resolve them. 

• The blower may remain unplugged. Plug the blower into a properly ground 120V outlet. 

• If the combustion shut-off system gets tripped, the water heater will deliver insufficient hot water. I recommend you call a certified technician to fix this issue. 

End-Note

A blinking blue flash on the status light will indicate a problem if you have a Rheem Power Vent Water Heater. The number of flashes on the status light will indicate a specific water heater problem. 

For example: 

• One flash every three seconds means a low-flame signal
• Two flashes every three seconds can mean the pressure switch failed to close
• Three flashes every three seconds will indicate an open draft pressure switch.
• Four flashes every three seconds can indicate a tripped TCO
• Five flashes every three seconds mean the flame goes out of sequence
• Six flashes of one, every three seconds mean a failed trial for ignitions. 
• Seven flashes every three seconds will notify you about flammable vapor sensor lockout. 

Read More:

• Rheem Power Vent Water Heater Troubleshooting
• Rheem Power Vent Water Heater Reset