How to Turn on a Gas Fireplace With a Wall Key

By
Lee Wallender
Lee Wallender
Lee Wallender

Lee has over two decades of hands-on experience remodeling, fixing, and improving homes, and has been providing home improvement advice for years.

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Updated on 06/05/24
Reviewed by
Deane Biermeier
Deane Biermeier
Reviewed by Deane Biermeier
Deane Biermeier is an expert contractor with nearly 30 years of experience in all types of home repair, maintenance, and remodeling. He is a certified lead carpenter and also holds a certification from the EPA. Deane is a member of The Spruce's Home Improvement Review Board.
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Fact checked by
Emily Estep
Emily Estep
Fact checked by Emily Estep

Emily Estep is a plant biologist and journalist who has worked for a variety of online news and media outlets, writing about and editing topics including environmental science and houseplants.

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Gas Fireplace

dpproductions / Getty Images

In This Article
Project Overview
  • Working Time: 1 - 2 mins
  • Total Time: 4 - 5 mins
  • Skill Level: Beginner
  • Estimated Cost: $0 to $10

Gas fireplaces can't be beat for the perfect combination of comfort, low maintenance, and ease of operation. Gas is clean, and it burns warm. Plus, you never need to clean up ashes later on. 

While some gas fireplaces ignite with the flip of a wall switch, or even by remote, other fireplaces are lit by turning a wall key, or a hex key, while applying flame from a lighter or long match. Operation is fast, easy, and safe—as long as you follow the lighting procedure correctly. Learn more about how to turn on your gas fireplace with a wall key.

Where to Find the Gas Valve Knob

Turning off the gas to the fireplace before cleaning

The Spruce / Almar Creative

The gas valve knob is the junction between the main gas pipe and the gas fireplace. When closed, the gas valve knob prevents gas from flowing into the fireplace. When opened, gas will flow. The valve can be opened partially or in full.

Look for a decorative slot near your fireplace. The gas valve knob is usually behind the slot and has a round metal flange with a square or hex hole in the center. The slot and knob will be located in one of these areas:

  • On the wall on either side of the fireplace, usually about a foot off the floor
  • Ground level on the fireplace apron
  • Ground level on the flooring around the fireplace

Tip

Usually, the gas valve will be no more than a few inches away from the fireplace. The valve must be close by so you can turn on the gas and ignite the fireplace at the same time.

Safety Considerations

Although natural gas is colorless and odorless, it is flammable and potentially dangerous. To help with detection, gas companies treat natural gas with trace amounts of mercaptan, a pungent odor similar to rotten eggs or sulfur. 

If you smell significant natural gas build-up in the home, turn off the gas to the fireplace, open all windows and exterior doors, and leave the house until the smell is gone.

Do not force the key when turning. This may break the gas valve knob or the key.

Warning

Never turn on a gas fireplace valve with a makeshift tool. You risk not being able to turn off the gas quickly in the event of an emergency. Only use the wall key designed for the gas valve.

What You'll Need

Equipment / Tools

  • Gas fireplace key
  • Kitchen lighter (if not using long matches)

Materials

  • Long matches

Instructions

How to Turn on a Gas Fireplace With a Wall Key

  1. Locate Gas Valve Knob

    Find the gas valve knob's decorative slot on the wall or floor. Place the key nearby. Do not place the key in the valve yet.

  2. Open Front of Fireplace

    Open up the glass doors or screen to the fireplace.

  3. Locate Ignition Area

    There will be a pipe with holes or valves on (or around) the log insert. This is where you will light the fireplace.

  4. Prepare Ignition Source

    Get the kitchen lighter or long matches ready to use but do not light them yet.

  5. Place Key in Gas Valve

    Insert the wall key in the gas valve. Make sure that the key fully seats in the valve. Do not turn yet.

  6. Light Ignition Source

    Turn on the lighter or strike the match. Hold the flame about 1/2 inch above the ignition area.

  7. Slightly Turn on Gas Valve

    Rotate the wall key a quarter or half turn counter-clockwise. Do not turn it on all the way yet. The flame should light.

  8. Turn Gas Valve on Full

    Continue slowly turning the valve counter-clockwise until the valve stops. If you decide to have a lower flame, stop short of this. Be careful not to turn it down too low, or you risk extinguishing the flame with gas still flowing.

  9. Remove Wall Key

    For safety, remove the wall key so does not break off or accidentally turn.

  10. Turn off the Gas Fireplace

    To turn off the gas fireplace, replace the wall key. Turn the wall key clockwise until it comes to a firm stop. The flame will taper down and extinguish on its own.

Troubleshooting Turning on a Gas Fireplace With a Wall Key

Cannot Find the Pilot Light

Wall key gas fireplaces do not have pilot lights. Manually lighting the fireplace substitutes for the pilot light. Gas fireplaces that operate with wall switches do have standing pilot lights, though.

Gas Flows but Won't Light

Turning the wall key alone will not light the gas fireplace. You do need to apply a flame to flowing gas to light the fireplace. If the gas is flowing but there's no flame, the problem may be with the flame. Turn up the flame on the kitchen lighter or use a new lighter.

Wall Key Is Lost

It can be easy to misplace the fireplace wall key since it should never be left in the gas valve knob. Look for it on the fireplace mantel, fireplace apron, or nearby shelf or cabinet. If you can't find the key, you can find a new one for a few dollars at your local home center or hardware store.

When to Call a Professional

Call a licensed plumber for any issues relating to the gas line within the house. Not all plumbers are equipped to work with gas lines, so check with them in advance. If you smell a gas leak outside of the house, call the gas company immediately. 

FAQ
  • Why does my gas fireplace have a key to start it?

    Some types of gas fireplaces have keys to start them and control the flow of gas. Other types of gas fireplaces are turned on electronically.

  • Are all gas wall fireplace keys the same size and shape?

    Wall fireplace keys come in all shapes, designs, sizes, and lengths (the standard is 3 inches long). However, there are universal keys that fit the keyhole valves of various fireplace models.

  • What can I use instead of a wall key to start my gas fireplace?

    It's recommended that you do not use a makeshift item to start a gas fireplace because you may not be able to turn it off in an emergency. Find a new wall key at a hardware or home improvement store or contact the manufacturer of your fireplace to inquire about a replacement key.

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