heater blower on 1997 Ford E-250

my heater doesn't blow air @ any setting. you can feel warm air but the blower isnt working. I ordered a blowere relay but not sure where it goes in fuse box. I don't have a diagram

Asked by for the 1997 Ford E-250
Sounds like a blower motor resistor, located at the plunum ner the blower motor.