Rheem Water Heater Light Flashing 7 Times

The Short Answer: Seven flashes mean different things on different Rheem gas tanks. On a standard atmospheric heater with a pilot, Rheem lists seven red flashes as a gas control (thermostat) failure. On a power-vent heater with a blower on top, seven flashes is a flammable vapor sensor lockout. Work out which you have, remove any flammable products from the area, and call a technician.

Which heater do you have?

• Atmospheric (standard) gas tank: a metal flue goes straight up from the top, there’s no blower and no power cord, and the gas control has a pilot. The status light flashes blue once every few seconds when everything is normal. Fault codes flash red.
• Power-vent gas tank: a blower sits on top, connected to plastic vent pipe, and the heater plugs into an outlet. On Rheem PowerVent models with the Honeywell electronic control, Rheem’s service bulletin refers to a blinking blue light on the gas control.

Count carefully. Watch two full cycles: the light flashes a set number of times, pauses about three seconds, then repeats. A single blue flash on an atmospheric heater is normal operation.

Atmospheric heater: gas control failure

Rheem’s manual says to contact a qualified service technician for seven flashes on its atmospheric models. The control itself has detected an internal problem. There’s nothing for an owner to reset, and repeated relighting won’t help. The technician will confirm the code, check the thermopile and wiring to rule out a supply problem, and replace the gas control if needed. A new gas control on a sound tank is a normal repair.

Power-vent heater: flammable vapor lockout

The flammable vapor sensor shuts the heater down when it detects fumes from gasoline, solvents, paint, adhesives, or similar products near the base of the heater. Rheem’s power vent manual lists the steps for this code: make sure no gasoline or flammable vapors are present, reset the gas control, and replace the sensor if the lockout continues. This lockout doesn’t clear on its own.

What you can do:

1. Remove gasoline cans, paint, solvents, and aerosol products from the room and ventilate it.
2. Don’t operate switches or create sparks if the fumes are strong; leave and call for help instead.
3. Once the area is clear, have a technician reset the control and inspect the sensor. If no vapor source can be found and the lockout returns, the sensor is likely faulty.

What the technician will check

On either type, the technician will read the code, confirm what model and control you have, and check the thermopile or power supply and wiring. For a vapor lockout they look for the vapor source and test the sensor. For a gas control failure they confirm the control has failed before replacing it.

For other Rheem codes, see Rheem 9 red flashes and Rheem gas control or valve failure.

Frequently Asked Questions

Q: My Rheem light is blue, not red. Does that matter? A: On Rheem atmospheric heaters a single blue flash is normal, and fault codes are red. On power-vent heaters the light behaves differently. Note the color, count the flashes, and check which type of heater you have.

Q: I moved the gas can. Will the heater restart on its own? A: On power-vent models, Rheem lists the flammable vapor lockout as indefinite, so it needs a reset after the vapors are gone. Have a technician do it and check the sensor.