Hi guys,

new guy on here, working on a HEIL Model # H9MPD075F12A2 that is tripping the rollout swith after watching the thing run and start many times it has become evident that there is no flame rollout it is simply overheating and it is only the right switch which mounts a little higher on the box than the left side, I have switch the switches around and it trip on the same spot. the furnace does have a little higher than normal heat rise but nothing to alarming maybe 50-60 but it is already on med-hi speed. filter clean and all registers open. pressure on the collector box is 2.80" H2O unfortunatelly cant get a reliable reading @ the burner box as its cabinet not just the box. Both intake and exhaust returned my golf ball, so not sure if I want to condem the secondary HE or is something else going on. I wish there was some data on the design static of the draft @ the collector box oddly enought I think it is related to the high heat rise but how?