This 4 3/4" combustion blower fan blade is the single-sided impeller that is used on the Heatilator Eco Choice BIO-120 Pellet boiler.

Ifany of the petals (fins)are bent, your stove may vibrate. To fix this, you can sometimes bend them back to help balance the motor. It is suggested to replace the impellerif the metal is corroded,if there is metal missing or if the impeller is unbalanced through wear and tear.

If you are replacing your combustion blower motor for any reason, it is suggested to also replace the impeller