Depending on which model optional blower you have, either one requires that the fan switch be turned ON for it to operate (manually or automatically). Also be sure that the blower cord is plugged into a functional* wall outlet. I have included a link to the Owner's Manual for your model Direct Vent Heater. In case you have misplaced yours. Starting on page 18, you will find the 2 optional blower models.Determine which one you have and follow their suggested recommendations, as one requires oiling several times during the heating season.
* "Functional" meaning there is power to that outlet and a circuit breaker has not been tripped.
If you continue to have an unsolvable problem contact Empire Comfort Systems Technical Service Dept 800-851-3153. The blower has a I year warranty. If you have your dated Proof of Purchase, repairs or replacement may be covered.
Hope this helped you and thanks for choosing FixYa.