Reliance Gas Water Heater Status Light Not Blinking

The Short Answer: On a Reliance atmospheric gas water heater, a status light that isn’t lit or blinking usually means the control is off or the pilot is out, so the thermopile isn’t producing enough power to run the control. Check that the gas is on, then relight the pilot following the label on the heater. If the pilot won’t light or won’t stay lit, a technician needs to find out why.

Why the light goes dark

Reliance is an A. O. Smith brand. Its atmospheric gas heaters use a gas control powered by a thermopile, a sensor heated by the pilot flame that generates a small voltage. There is no battery or household power. When the pilot goes out, the thermopile cools, the control loses power, and the status light goes dark.

Reliance’s instruction manual (opens in a new tab) lists “0 flashes (LED not lit)” as the control being off or the pilot not lit, with not enough millivolts to keep it lit. The same table describes:

Other flash counts point to sensor, control, or flammable-vapor issues and are listed on the label on your heater. If your heater has a blower on top and a power cord, it is a power-vent model with a different control; check its own manual.

What you can check safely

1. Gas supply. Make sure the gas valve on the pipe to the heater is open (handle in line with the pipe) and that other gas appliances work. If you use propane, check the tank level.
2. Control setting. Check that the gas control knob isn’t set to OFF.
3. Wait if the light is solid. A steady light means the thermopile is still cooling. The manual asks you to wait before relighting.
4. Relight once using the lighting instructions on the label on the heater.
5. Air intake. Look at the air-intake screen near the base for lint or dust and clear the area around the heater. Move gasoline, paint, and solvents away.

If the pilot lights but goes out again, or the light comes back with a flash code, note the pattern and call for service.

What the technician will check

A technician will check the pilot flame and its position on the thermopile, measure the thermopile’s output with the control connected (A. O. Smith’s service note (opens in a new tab) gives the minimum it should produce), check whether a thermal switch on the combustion chamber has tripped, and inspect the air intake and burner area. If the thermopile output is good and the light still won’t blink, the gas control is the likely failure.

Repair or replace

A thermopile, pilot assembly, or gas control is a repair on a sound tank. A tripped thermal switch needs its cause found, such as a blocked air intake or venting problem, before it is reset. A leaking tank or heavy rust at the base means replacement.

Related: Reliance water heater won’t light, why won’t my gas water heater stay lit, and water heater thermocouple problems.

Frequently Asked Questions

Q: Is it normal for the status light to be off between heating cycles? A: No. On these controls the light blinks once in normal operation whenever the pilot is lit, even when the burner is off.

Q: The pilot is lit but the light is still off. What does that mean? A: The thermopile may not be producing enough power, the pilot flame may not be reaching it properly, or the control may have failed. A technician can measure the thermopile to tell which.

Q: Does my Reliance electric water heater have a status light? A: Standard Reliance electric tanks don’t use this gas-control status light. If an electric heater is cold, start with the breaker. See water heater element not working.