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a code 12 flash on a board that doesn't have a 12 in the legend
I am thinking that this control board is bad because control boards can't self diagnose themselves.the furnace is a York model #GY8S080A12UH11D.serial# WOH716411.order# 005004622169(if this means anything).it has an Emerson WR 1194V0 attached to it that flashes red 12 times while the blower runs. the legend doesn't have a 12 listed for a code.On a call for heat the inducer runs for a second and then the blower comes on and the inducer stops and the board flashes red 12 times.I disconnect 1 wire at the high limit and then the inducer starts again,the igniter glows but no ignition and flashes 12. There was another guy before me that had installed a new inducer when the old one found nearby still worked when I plugged it in. he had also replaced the blower too-this time I didn't find the old one nearby.When I got there the other night it flashed twinning or 24 volt phase incorrect and the high limit was jumped.this unit did not work at all.i managed to find that it was grounded to a screw that was holding down the transformer that had a shellac coating on it which prevented it from grounding. I screwed that wire to a hole in the side of the blower shroud I no longer got that code anymore.so the sequence started - call for heat,blower comes on for I guess for 90 seconds,shuts off, then inducer runs for so many seconds,glow bar glows and then the burners come on and runs. is this the right sequence? I thought that the inducer is supposed to run first then after the burners are running the blower will come on for whatever time is set on the jumper.I noticed this happens on a goodman as well.blower for 90 seconds-blower off-inducer 90 seconds-ignition..well anyway I got it from a no start to running while the blower compartment door was off and it ran and ran after I had the previously jumped high limit wires reconnected back to where they belong. So I thought that the job was done until shortly after I put the compartment door back on.I reached it's high limit and then the burners shut down while still on a call for heat.I found the culprit to be a 8"x8"(approximate) square for a return in the side of the cabinet.so since it was 3:30 a.m. I was too tired and decided to leave the cabinet door on and just let it cycle that way-at least they had some heat until I come back and fix it for another day.On top of the other things I had to do to it.very poor install. the starting collar on the reducer was missing so the stack which was too large was just sitting on top of the outlet,the stack pipes where rusted out with holes and it was loosely connected at the chimney as well.
drain cleaning, plumbing,heating and electrical repairs.