American Standard Freedom 80 - Burner Flame Size Problem

[tchad2012]

I'm new to the forum and have had problems since a recent power failure. Had to replace HSI and control board after power company caused an instantaneous power failure.

Everything is working ok now, except for one problem. My furnace is mounted horizontally, and the flames on the burners are okay until I put the louvered furnace cover on. Once I do this, the flames immediately spread outside of the proper distance (spread maybe 2-3 inches out). Anyway, this is enough to burn part of the insulation off of the HSI wires. If I remove the cover, the flames retreat to the proper size. So, I'm currently running the furnace with the louvered cover off until I can determine what is causing this strange situation.

Any suggestions would be most appreciated.

[HayZee518]

furnace

I guess first question is - is the furnace made to be mounted horizontally?

[tchad2012]

Horizontal Furnace

Yes. The owner's manual says it is "gas furnace - induced draft - upflow/horizontal and downflow/horizontal - single stage heat". I bought the house 3 years ago and this is the first trouble we've had with the furnace. Don't know when it was installed.

[Centurian]

furnace

I'm no expert..but it sounds to me there is inadequate combustion air which is causing the flames to seek oxygen when you put the cover on...it is called flame roll out and there is a safety switch above the flames which should cut out if this happens...not being disrespectful..but have you changed the filter

[tchad2012]

Thanks for the reply, Centurion. Yes, the filter has been changed. It's one of those 4" thick 3M Filtrete filters.