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does your circuit board have a blinking light? or is this unit older than 20 yrs?
please try a cycle and tell me if the light blinks after failing to start...or if the system never tries and light stays solid
turn thermostat to HEAT mode and turn setting higher than current room temp
Do you mind removing top section of the thermostat to where we can see wiring?
then tell me if you see terminals R and W
thank you,,,,the code is 2 digits. short blinks then long...can you tell me the pattern?
thank you....and you are sure the system starts exhaust fan...there is no glow from ignitor....and then 34 appears
ok, first llets locate the sensor rod at opposite end of burners from ignitor.....clean this rod with steel wool and tell me if the system starts to run better
correct...is that the code after cleaning the flame sensor?
ok, when the flame happens....does it fully cross the burners all the way to the other side?
ok do you have verified gas supply to the furnace? does the gas valve click?
and does the gas valve click?
I dont know what happened...but I ask if the gas valve clicked and then the response 3 hrs later said problem still not fixed. Does the gas valve ever click when ignitor is glowing?
the gas valve is what is attached in the gas pipe before the pipe goes into the burners.
First of all give me the complete model on furnace.It will be on a label inside above burners on right or left side panel and will begin with numbers 58.(EX. 58STA80). Next tell me if you have a volt meter for troubleshooting.
Turn power off to furnace then back on,Call for heat and tell me how far in sequence it goes and very first error code we get.
OK our next step is to locate the gas valve inside the unit. The valve outside is just a gas cock, not an actual valve. Now after locating gas valve on burner manifold, what we want to do is get a volt meter and check between the two wires at gas valve to see if we get 24 volts ac when igniter glows..See below
That is it. If you can attach a picture I will show you where to check for the 24 volts.
If you have a paper clip icon on your page you can attach using that link.Or
You can upload the pictures using the tiny pic site .
Here is a link to the site.
Click on Browse , select the file from your folder.then click UPLOAD NOW.
They will give you a quote to enter in the box to verify you are a human.Enter the quote and click UPLOAD NOW
You will see your picture on right side of screen.
Then copy the link URL for email & IM
Paste that link here on the site.
Without a meter we are guessing.You can replace gas valve and control board ,but I would rather get a meter and determine the issue rather than guess.
You can get an inexpensive one at Walmart for about 15 bucks if you would like to troubleshoot and I would be happy to guide you.
I understand.Toubleshooting almost always requires a meter for testing voltage.I could throw out a guess but would be less than professional to do so.
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