I had a tech at my house recently and he adjusted the blower speed on my unit due to low "delta T" .
I now notice that the furnace kicks on and runs no problems. Then the thermostat reaches the set point and clicks to turn the furnace off and the blower cycles up to a higher speed for about 90 seconds.
I didn't notice it before the blower speed was adjusted.
Is this normal? (goodman 93% eff furance downflow)