With the fan switch in the on position and heating or cooling called for, {TAIL ~ the control} causes the blower to operate at {HEAD ~ a high speed}, which may be different for heating or cooling 
With the fan switch in the on position and heating or cooling called for , { TAIL ~ the control } causes the blower to operate at { HEAD ~ a high speed } , which may be different for heating or cooling
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH