no heat on 1991 Chevrolet G Series Van (G20)

heater blows cold air when turned on.

by in Spokane, WA on October 13, 2010
3 answers
ANSWER by , October 13, 2010
themostat stuck open or heater core plug
ANSWER by , January 25, 2011
could be heater control valve located just in front of heater core
ANSWER by , May 06, 2014
I noticed mine blowing coldish on the feet only this winter when I took it for a trip.