Screwy logic with Lennox's Mod. Uses a 2 stage stat. Once stat calls for higher fire, won't go back down. How smart is that? Rheem's Mod still the only one that uses a stat that knows setpoint and room temp and tells the furnace what to do based on that. Nordyne's new one I hear will do it by stat too. No data on it yet that I've seen beyond hearing that.