The basic steps to relight your Rheem water heater

To light a Rheem gas water heater pilot light, turn the gas control knob to the OFF position and wait five minutes for any gas to clear. Then switch the knob to PILOT, hold down the ignition button (usually red or black) while holding a lit match or lighter to the pilot burner opening at the bottom of the tank. Keep the button pressed for 30 to 60 seconds after the flame appears. Once the pilot stays lit, turn the knob from PILOT to ON.

The whole process takes about two minutes if you have a working lighter or matches nearby. Most Rheem units have the pilot burner opening on the front-facing side of the combustion chamber, roughly 4 to 6 inches from the bottom of the tank. If you cannot see the opening or reach it easily, a flashlight and a long-reach lighter make the job simpler.

Key Takeaways

  • Turn the gas control knob to OFF, wait five minutes, then switch to PILOT before attempting to light the flame.
  • Press and hold the ignition button while explore a flame to the pilot burner opening until the pilot light catches and holds steady.
  • Keep the button pressed for 30 to 60 seconds after ignition to allow the thermocouple to heat up and sense the flame.
  • If the pilot will not stay lit after three attempts, the thermocouple or gas valve may need replacement by a licensed technician.

Where to find the pilot light controls on a Rheem unit

The gas control knob is mounted on the front of the water heater's lower section, usually within 12 inches of the bottom. It is a round dial with three positions marked: OFF, PILOT, and ON. Below or beside this knob, you will see a red or black button labeled IGNITION or SPARK. This button is what you press and hold while lighting the pilot.

The pilot burner opening itself sits inside the combustion chamber, visible through a small opening on the front face of the heater. You may need to crouch or kneel to see it clearly. If your Rheem model has a glass viewing window, the pilot flame should be visible through it once lit — it will appear as a small blue flame about the size of a pea.

What to do if the pilot light will not stay lit

If the pilot flame goes out when ready after you release the ignition button, the thermocouple is likely not sensing the heat. Press and hold the button for the full 60 seconds on your next attempt, keeping the flame directly on the pilot burner tip. The thermocouple needs sustained heat to trigger the gas valve to stay open.

If the pilot still will not hold after a second or third attempt, the thermocouple may be dirty, bent, or faulty. A thermocouple is a safety device that shuts off gas flow if no flame is detected. Cleaning it requires removing the burner assembly, which is a task best left to a licensed plumber or HVAC technician. Replacing a thermocouple typically costs between $150 and $300 in labor and parts.

Safety steps before you begin

Before touching any controls, make sure the area around the water heater is clear of flammable materials — newspapers, cardboard, cleaning supplies, and paint cans should be at least 3 feet away. Check that there are no gas leaks by smelling around the unit; natural gas has a distinctive rotten-egg odor added by the utility company. If you smell gas, do not attempt to light the pilot. Leave the area, call your gas utility's emergency line, and wait for their technician.

Wear long sleeves or use a long-reach lighter to keep your hand away from the pilot burner opening. The area around the opening can be hot even when the pilot is not lit, especially if the heater has been running recently. If the water heater is in a confined space like a closet, prop the door open to allow fresh air to circulate while you work.

Tools and materials you will need

A long-reach lighter or long fireplace matches are the easiest tools to use. Standard kitchen matches work but require you to hold your hand closer to the burner opening. A flashlight or headlamp helps you see the pilot burner opening clearly, especially if the water heater is in a dark basement or utility closet. Some people find a small mirror useful for angling light into the combustion chamber.

You do not need any special tools or replacement parts to light the pilot. If you have a Rheem manual for your specific model, it may include a diagram showing the exact location of the pilot burner and the ignition button, though the layout is similar across most Rheem residential units.

When to call a professional instead

If the pilot light goes out repeatedly even after you have held the ignition button for a full minute, or if you smell gas during the lighting process, stop and contact a licensed plumber or HVAC technician. A faulty thermocouple, a cracked gas valve, or a blocked pilot tube all require professional repair and cannot be fixed by relighting alone.

If you are uncomfortable working near gas appliances or if your water heater is under warranty, calling a technician is the safer choice. Many utility companies offer free or low-cost inspections and repairs for gas appliances, so check with your local provider before paying for a private service call.

Frequently Asked Questions

How long should I hold the ignition button down?

Hold it for 30 to 60 seconds after the pilot flame appears. This gives the thermocouple time to heat up and signal the gas valve to stay open. If you release too early, the flame will go out once you let go of the button.

What does the pilot flame look like when it is working correctly?

A healthy pilot flame is small and blue, about the size of a pea or a grain of rice. It should be steady and not flicker. If the flame is yellow or orange, the burner may be dirty and could benefit from professional cleaning.

Can I light the pilot without the ignition button?

Yes, you can use a match or lighter alone, but you must still turn the knob to PILOT first to allow gas to flow to the burner. The ignition button is optional — it just makes the process easier by creating a spark. Holding a flame to the opening works just as well.

Is it normal for the pilot to go out during a power outage?

No. The pilot light runs on gas and should stay lit even if the power goes out. If it goes out during an outage, the thermocouple may be failing, or there may be a draft problem. Once power is restored, try relighting it. If it goes out again, contact a technician.

How often do I need to relight the pilot?

Under normal conditions, the pilot should stay lit indefinitely once you light it. If you find yourself relighting it more than once or twice a year, the thermocouple or gas valve is likely wearing out and should be inspected by a professional.