CAN'T LIGHT THE PILOT FLAME - Rheem 40 Gallon FVR NATGAS Low WATER HEATER 6YR 22V40SF

yes it will, the pilot flame hits a flame sensing device called a thermocouple this device sends a signal to the gas valve and shuts the main valve when therre isnt a flame signal; however, its never a bad idea to manually shut off the gas when youve lost pilot flame.

Not sure what screen you refer to, but the simple fix, assuming you have done all the correct pilot re-light procedure's, the cheapest part to try is a Thermocouple, easy enough to try it DIY.

Remove the pilot injector from old unit and fit into new unit

More than likely the thermal couple is defective. The thermal couple is a safety device that shuts the gas off if the pilot goes out. If it is defective the pilot light will not stay lit. The thermal couple is the device that the small copper line goes to. It is mounted beside the pilot flame and the flame much touch the TC for it to work. If the flame is not touching the TC bend it until it is in the flame. If it is touching the TC then replace it.

The pilot light jet may have got a little bit of dirt or grit in it which is preventing it from keeping alight. Try probing the jet with a fine piece of wire to see it the blockage can be dislodged. You may have to unscrew the jet to clear it by blowing air through it. Make sure gas is turned off first before removing any parts.

The pilot light also has a thermocouple that allows gas to the pilot light while the flame is burning. If flame goes out it shuts gas off to the pilot jet. The thermocouple is bypassed by a switch during the initial ignition and once the thermocouple warms up after a minute or two of holding in the bypass switch, it should maintain the pilot. If, after cleaning, the pilot light keeps going out, it would seem that your thermocouple is faulty and needs to be replaced

The pilot light has a thermocouple that allows gas to the pilot light while the flame is burning. If flame goes out it shuts gas off to the pilot jet. It seems that your thermocouple is faulty and needs to be replaced if pilot light keeps going out as the outside air cools.

You need a new thermocouple - or maybe the Pilot flame is not lined up properly to the thermocouple? The thermocouple is a "sensor" that is heated by the flame - which in turn keeps the gas supply to the pilot light on. It the pilot light goes out, then the thermocouple no longer "senses" the heat of the flame, so it turns the gas supply off to the pilot to prevent buildup and explosion.

The pilot light is working so you know you have gas but you also know that the gas is not coming on. The pilot flame should be bright blue with the tip of the flame having a ting of yellow. A yellow flame is caused by a dirty pilot tube tip. Split flame is caused by dirt in the pilot tube. If the flame is not hot enough it will not tell the thermocoupler to turn the gas on. If the thermostat has not been moved and is still at the correct setting then I would suspect the thermocouple is bad. The thermocouple is mounted right next to the pilot light. It senses if the flame is hot enough for the gas to come on. If the pilot flame is not touching the coupler then it will not allow the gas to be turned on to the burner. Check the thermocoupler and see if the flame is touching the probe on the end. If not adjust it until the pilot flame is touching the coupler. If the flame is properly adjusted then replace the thermocoupler but shut off the gas supply before doing so. It will look like this.

replace the thermo

The steps involved can vary slightly depending on your furnace model and pilot valve type, so if possible try and find the instructions inside the furnace door cover or in the instruction manual. This is for a gas fired furnace, but applies to any gas-fueled appliance including water heater. Two of the most common types of pilot valve body assemblies either have a red reset button and a gas valve or no reset button and a valve knob that can be depressed. But whichever type you've got, if you have an older model furnace with a standing pilot (flame is lit all the time) then this is the basic procedure.

• 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 **** or valve knob that reads "On, "Pilot" and "Off." Locate this gas **** or knob.
• Turn the knob or gas **** to the "Off" position and wait about 3 minutes for any residual gas to clear away.
• Find the pilot. It's located near the 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 as appropriate. 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 **** 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. You'll need a furnace service technician to replace or repair these parts. You may find that the pilot lights, but it is an anemic looking flame. That's a different problem we'll look at in the next section.
  
• 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. Adjusting the Flame
  There is usually a small screw on the pilot valve body that will adjust the flame. You may have to refer to the manufacturer's instructions to find the screw. Turn the screw as needed to adjust the flame throw. Yellow Flame
  A yellow flame is caused by lack of air and incomplete combustion. It can be caused by a dirty pilot tube tip. Split Flame
  This is caused by dirt in the pilot tube. Take a needle or small nail and gently clean the tube. Flickering or Wavering Flame
  A flame that flickers is usually caused by a draft.
  

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