Lighting a Pilot Light

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If you are unsure if you have the knowledge and/or skills to carry out the tasks below without injury to yourself, others, or your property, please contact us.

Turn you thermostat to 80 degrees or to a setting that will demand heat. Make sure the thermostat is in "Heat" mode.

Go to the furnace and find the pilot valve. The pilot valve body is a box shaped device into which the main gas line will run and is located near the gas burners. It will usually have a gas cock or valve knob that reads "On, "Pilot" and "Off." Locate this gas cock or knob.

Turn the knob or gas cock to the "Off" position and wait about 3 minutes for any residual gas to clear away.

Find the pilot light. It's located beneath the horizontal gas burner tube assembly in the furnace.

Get your match or lighter ready. Sometimes the pilot is hard to reach. If possible, try and use a long fireplace match when you light it. If you don't have a fireplace match then a butane BBQ grill lighter works well too. If you don't have that, then you can fasten a match to the end of a stick when you light the pilot.

If you have a pilot with a red Reset button, turn the gas valve from "Off," to "Pilot."

If you have a pilot with no red button, turn the knob from "Off" to "Pilot."

Place the lit match or ignited lighter tip at the pilot and depress and hold the button or depress the knob, whichever one you have. Depress the button or knob for about 30 seconds. This maintains gas flow to the pilot until the thermocouple gets hot enough to open the main gas valve.

Once the pilot stays lit, slowly release the button or knob and turn the gas cock or knob from the "Pilot" position to the "On" position. This will ignite the burners and keep the flow of gas supplied as required for the burners as called for by the thermostat.

If the burners fail to ignite then it may be because the thermocouple did not get hot enough to open the gas valve. Wait a few minutes and then repeat the above procedure. This time hold the red reset button or depress the knob for about 45-60 seconds.

Once the main furnace burners ignite, adjust the thermostat to the desired setting.

If you've followed the previous steps on lighting the pilot and it still does not light after, or will not stay lit, then you probably have a problem with the thermocouple or an adjustment needs to be made to the pilot. If you suspect this is the case, contact us.

If the pilot lights but the flame is a weak yellow flame, it will not get hot enough to heat the thermocouple to its set point allowing the gas valve to open.

A natural gas flame should be a bright blue with the tip of the flame having just a tinge of yellow. A propane flame should have a bluish green flame with a tinge of yellow at the tip. The flame should be strong enough to hit the thermocouple tip about 1/2 inch from the tip end. If the flame is weak or shaky looking, check to see that a breeze or draft is not blowing on it.

Yellow Flame - caused by lack of air and incomplete combustion. It can be caused by a dirty pilot tube tip. Contact us.

Split Flame - caused by dirt in the pilot tube.

Flickering or Wavering Flame - usually caused by a draft. Contact us.

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