We have two Trane systems in a two story home. The upstairs unit in about six years old 3 ton that runs at one indoor blower speed summer and winter. The new unit downstairs is a Trane TAM8 with a XL20i outdoor unit two compressor 2 and 4 ton that is variable speed. This is a fairly new system for the Trane with the Comfort Link stat.
My question has to do with indoor vent outlet temperatures. On any specific winter day, the upstairs unit is discharging warmer air at the fixed higher speed than the downstairs high efficiency unit at the variable speeds (the downstairs varilable speed blower is producing less air movement at vent than the upstairs unit). The upstairs thermostat is not showing auxillary heat being applied.
I would have thought the higher efficiency unit would put out much warmer air especially when the air is moving slower. Can anyone explain why the high efficiency unit is not as warm.