I recently had a Trane XV-90, two-stage furnace installed.
I can't say that I have ever been aware of the unit kicking into stage two. How will I know stage 2 is being utilized? (According to the installation manual the temperature rise for stage 1 (65% gas) versus stage 2 (100% gas) is only a couple of degrees at medium low fan speed (and that doesn't make sense to me.)
From reading the manual, it seemed to suggest that stage two is triggered when the room temperature falls at least one degree while operating in stage one, and then it waits 10 minutes before turning on stage 2.
Is this typical?
To me, the logic seems off. I would think if the temperature in the room remained either at the same number below the requested temperature for a certain period of time [e.g., you have it set on 68 but it can't get the room above 62 for x time), or a certain period of time has elapsed and the requested temperature is still not reached, then stage two would kick in.