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Tim H.
Tim H., HVAC Professional
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got a 13 year old janitrol gas furnace that is now not igniting

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got a 13 year old janitrol gas furnace that is now not igniting . Ive got 3 blinking lights. I was given some bad advice after the unit would only fully ignite on its own 80% of the time. I was told to disconnect hose and clean out nipple . I thought it was odd to do since the only problem was surface ignitor wouldnt always work. Now ive got no gas only the beginning start up of the fan located above the gas regulator. Now I dont have the gas being discharged to even fire up manually. Where do i go from here? Please give me some feed back.

Thanks Dylan
Hi, I'm Tim and I'm an HVAC expert here to assist you with your questions. Thanks for the opportunity to help!
Without the specific model, I can't be positive, but from doing some research, the 3 flash code points to a pressure switch failing to close. This could be a bad pressure switch, inducer motor, blocked vent, etc.
Have you checked any of these things yet?
Customer: replied 3 years ago.

Where is model number located normally on this furnace.

Should be inside the top door somewhere on a tag. The flash code legend that tells what the number of flashes means may be down inside the blower compartment somewhere
Customer: replied 3 years ago.

Sorry no model number that can be located i have looked in the past and I do apologize . Why am I now not getting any gas to ignite?

Because your pressure switch is not closing.
Customer: replied 3 years ago.

Where exactly is the pressure switch and how can i get it functioning again it was working until I pullled hose to inspect

It is a round looking device. maybe black or silver in color and has an orange or grey hose going to it.
Customer: replied 3 years ago.

Okay i have located it now what would be my next step

(see above.) This could be a bad pressure switch, inducer motor, blocked vent, etc. It could be a kinked pressure switch hose or the barb that the hose attach's to on the furnace is plugged.
Customer: replied 3 years ago.

Okay just detached it all from back wall of furnace cleaned it all out checked for blockage and found none and no kinks in hose.

There should be two wires going to top of pressure switch. If you wait until inducer motor gets up to full speed and put these together, furnace should run. Since you found nothing wrong with hose, could be bad switch, slow inducer motor, blocked vent, etc.
Customer: replied 3 years ago.

I was able to jump the two and got it to fire up.

OK, so now we just have to figure out what's causing it. If vent to outside is clear, then it could be an inducer motor that's slowing down or even a bad pressure switch. Pressure switches are not easy to diagnose (requires a manometer and the knowledge of how to us it) so, you may want to try replacing it and see if that solves the problem. They are not terribly expensive.
Tim H. and 2 other HVAC Specialists are ready to help you
Customer: replied 3 years ago.

Can I go online for that I do have an account at R E Michaels but I dont think the would carry that specific switch but i have had luck on ebay for boards and other related controls. Now just to let you know the entire reason why I was even messing with this furnace was because the new surface ignitor I installed wouldnt always ignite. What control is bad or going bad to not tell that glow plug to turn on every time heat is trying to kick on. Ive been watching it . For the most part it fires up on its on but every now and then it wont and will go into lockout mode with 1 blink from the board.That was really the answer im chasing until I ran into this other problem with this switch.

Remember, if the pressure switch isn't made---NOTHING further will happen on the furnace.