What temperature difference does boosted airflow make?
This is dependent on a host of variables. How well insulated is the room? What heat gain in the summer through a window? How far is the register from the furnace? Is this room over an unheated garage? Etc. Here is an example: During the winter heating season, you need a room about 4 F warmer than it is. To achieve this you will need 11% more airflow out of the register(s) in that room assuming that your furnace runs 60 minutes out of the hour. If your furnace runs 20 minutes out of the hour on a cold winter day, that is 1/3 of an hour. You will need 3 times the 11% or 33% boost. In most applications, an In-Line Duct Fan will boost up to 80%. Thus, well up to the task of warming up a room.
