Heater Pilot lites then nothing
#1
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Heater Pilot lites then nothing
I have a have a Carrier three wire pilot ignition system
I have done work on it before, changed the electrode.
Read more: http://www.doityourself.com/forum/ga...#ixzz1jV0rtBNs
Now the problem I have is that pilot lites and then the two long rods above light up about a minute after. The rods stay on for a while then when its about time for the blower to go on the rods turn off. The pilot stays lit but that is it. I have checked the fuse for the blower and it looks fine, what could it be? Any Ideas?
I was just in the garage and this time it went through the whole cycle like normal, blower now stayed on for about 2 minutes. Then stopped.
I have done work on it before, changed the electrode.
Read more: http://www.doityourself.com/forum/ga...#ixzz1jV0rtBNs
Now the problem I have is that pilot lites and then the two long rods above light up about a minute after. The rods stay on for a while then when its about time for the blower to go on the rods turn off. The pilot stays lit but that is it. I have checked the fuse for the blower and it looks fine, what could it be? Any Ideas?
I was just in the garage and this time it went through the whole cycle like normal, blower now stayed on for about 2 minutes. Then stopped.
Last edited by blanquitoman; 01-14-12 at 09:32 PM.
#2
The "long rods" are, I suppose, the burners on which the gas burns and which have burner ports down their length?
About the only thing that will allow the burners to light and shut off but the pilot to remain lit is a dirty pilot burner which needs to be taken apart and cleaned.
Shut the power off to the furnace.
There may be a flame shield blocking access to the burners and pilot burner. Use a 1/4" nut driver to remove the screws that hold that in place and remove it.
Use a 1/4" nut driver to remove the screws which hold the pilot burner in place.
Gently pull the pilot burner out in front of the burners so you can work on it, bending the pilot tubing to do so.
Use a 7/16" open end wrench to loosen the brass ferrule that holds the pilot tubing in the pilot burner.
Pull thwe brass ferrule out and then remove the pilot orifice that is held into the pilot burner by the brass ferrule. Often it will just drop in your hand, but you may need to pry it out gently with a miniature screwdriver.
Use the wire from a wire brush to clean the small hole in the pilot orifice, and clean the pilot burner with a wire brush.
Also, it's a good idea to lift out each burner and brush off any dirt, rust and debris and reinstall it.
Reassemble and give that a try.
Cleaning the pilot burner is ordinary maintenance that should be done once per year, along with cleaning the burners.
About the only thing that will allow the burners to light and shut off but the pilot to remain lit is a dirty pilot burner which needs to be taken apart and cleaned.
Shut the power off to the furnace.
There may be a flame shield blocking access to the burners and pilot burner. Use a 1/4" nut driver to remove the screws that hold that in place and remove it.
Use a 1/4" nut driver to remove the screws which hold the pilot burner in place.
Gently pull the pilot burner out in front of the burners so you can work on it, bending the pilot tubing to do so.
Use a 7/16" open end wrench to loosen the brass ferrule that holds the pilot tubing in the pilot burner.
Pull thwe brass ferrule out and then remove the pilot orifice that is held into the pilot burner by the brass ferrule. Often it will just drop in your hand, but you may need to pry it out gently with a miniature screwdriver.
Use the wire from a wire brush to clean the small hole in the pilot orifice, and clean the pilot burner with a wire brush.
Also, it's a good idea to lift out each burner and brush off any dirt, rust and debris and reinstall it.
Reassemble and give that a try.
Cleaning the pilot burner is ordinary maintenance that should be done once per year, along with cleaning the burners.
Last edited by SeattlePioneer; 01-14-12 at 11:59 PM.
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Grounding in flame sensing
I agree with what was stated but noted two things to verify.
1. Make sure you use a wire brush to clean the rods as stated not regular sandpaper. I have had some DYI's use sandpaper not knowing the rod looks clean but leaves a silica residue. If you cannot use or have a small wire brush, use virgin clean steel wool.
2. Sounds as this problem has been intermittent. Make sure the furnace is properly grounded. (Not just a hot and neutral to furnace) A loose or missing ground wire can cause intermittent problems as well.
1. Make sure you use a wire brush to clean the rods as stated not regular sandpaper. I have had some DYI's use sandpaper not knowing the rod looks clean but leaves a silica residue. If you cannot use or have a small wire brush, use virgin clean steel wool.
2. Sounds as this problem has been intermittent. Make sure the furnace is properly grounded. (Not just a hot and neutral to furnace) A loose or missing ground wire can cause intermittent problems as well.