hvacnopro
01-25-2012, 02:39 PM
hey guys working on a unicell 90,000btu forced air up draft high efficiency furnace. original call wont stay on or heat space, easy enuff replaced pressure switch, condensate trap and repiped with all new lines. fixed right, wrong soon after call came back not heating... got there wouldnt stay lit cheack resistance of hsi over 90 ohms so replaced not the issue jumped out pressure swith roll out and induction heat saftey still will not stay lit cleaned burners intakes exhaust set hsi 5/16" from burner still wont stay lit the onlything left is the control board right? is there a way of checking the micro amps in the 7 secs of igniton or should i just replace board not burnt maybe its lost its logic or whatever any help????