: Refers to the Electric Heat capacity. The "20" indicates approximately 19.2 KW of supplemental heating, which translates to roughly 65,530 BTUs.
A patented feature in the RHQA-12 and higher models that stages supplemental heat. It limits the KW input to only what is necessary for the current demand, preventing energy waste. rheem model no rhqa 1220t pdf
: Identifies the specific Air Handler series designed for multi-positional installation (upflow, downflow, or horizontal). : Refers to the Electric Heat capacity