Discussion Starter · #1 ·
My Therma-Pride furnace model OH5-85 delays from 1 to 5 seconds about half of starts and when it ignites it does with an explosion and pushes out smoke around the chamber inspection plate. We have changed nozzle and set the electrodes and the normal checks and each time it seems to to ok for a few days and then goes back to the same delay procedure. This has been going on for about 2 or 3 winters. Heats and runs good otherwise. Help.