Home Fault Codes

Rheem Water Heater 4 Flashes: Meaning and Fix

Applies to: Rheem ProClassic power direct vent gas water heaters (natural or LP) with a flue damper, per the Gas Valve LED Codes table in the Use and Care manual; other Rheem and Ruud water heater lines can use different codes.

4 Flashes
How 4 Flashes appears on a Rheem water heater display.

Also shown as: Four Flashes

Reading the water heater display

A gas tank water heater reports its fault as a count of LED flashes on the gas control valve, seen through the small window or viewport near the base of the tank. Count the flashes, note the pause (usually three seconds) and watch a second full round before you decide which code it is. Some controls use two groups, such as six flashes then one.

Rheem makes gas furnaces, tank water heaters and tankless water heaters, and each line reports faults differently: status LED flash counts on furnaces and tank gas controls, numeric codes on tankless units. Use the table for the product family on your rating plate. Check the model label on your unit before using any chart.

What causes 4 Flashes

How to fix it

If you smell gas, leave the building and call your gas utility from outside; do not touch switches or the unit. Switch the water heater off and let it cool before you touch any internal part, and call a licensed plumber or water heater technician if you are not sure.

The code meaning comes from the manufacturer document listed under Sources. The causes and steps below are general troubleshooting guidance, not the manufacturer's service procedure.

  1. Turn the gas control knob to OFF. If you smell gas, leave the building and call your gas utility from outside; do not touch switches.
  2. Make sure the tank is completely full of water before the burner runs.
  3. Reset the gas control and check that it cycles normally.
  4. A technician should replace the gas control if it is faulty.
  5. If the code returns after these checks, call a licensed plumber or water heater technician and give them the flash count and the model number from the rating plate.

Questions

What does Rheem water heater 4 Flashes mean?

4 Flashes on a Rheem gas storage water heater with an LED on the gas control means the system is in lockout because the thermal cutoff device tripped. The manual lists a thermal well fault in the gas control, a faulty gas control, or a tank that is not filled with water. The Rheem manual lists this under Gas Valve LED Codes.

Can I reset the water heater myself?

Turning the gas control knob to OFF, waiting, and relighting it clears some codes. If the same flash count comes back, the fault is still there and the unit will lock out again. Do not bypass a safety device to keep it running.

When should I call a technician?

Call a licensed plumber or water heater technician for anything involving gas, venting, the pilot, the gas control or flammable vapor sensor, or when the code keeps returning after the simple checks.

Other brands with code 4 Flashes

The same code can mean something different on another maker's appliance. Check the brand before you act.

A. O. Smith water heaterTemperature exceeded, ECO activatedBradford White water heaterHigh tank temperatureChamberlain garage door openerSensor beam misaligned (sender steady, receiver dim)Craftsman garage door openerSensor beam misaligned (sender steady, receiver dim)Goodman furnaceOpen limit switchLennox furnaceLow flame signal, check flame sensorLiftMaster garage door openerSensor beam misaligned (sender steady, receiver dim)Trane furnaceOpen high limit device

Other Rheem water heater codes

1 FlashLow flame signal2 FlashesFlue damper switch closed3 FlashesFlue damper switch open5 FlashesNo flame sense6-1 FlashesUnit failed to light6-2 FlashesFlue damper switch opened

Sources

Part numbers are OEM references; confirm fit by your model number before ordering. Meanings compiled from manufacturer and parts-retailer documentation; see sources below. Unplug the appliance before opening it.