Chevrolet Repair: Replace the heater core, blazer s10, chevy blazer

Question
I have a 96 chevy blazer s10 that is my baby, but she has never had air and recently stop producing heat. I was told by a mechanic that i need a heater core. Do you think that i need one, and if i do, can it be install with basic tools? I have gone through one radiator already and i wish not to go through it again.

Answer
No you should not attempt replacing the heater core your self you need to take the whole dash out to access this part.  You could however try blowing throug the heater core with a garden hose and see if it removes the debris from inside the core.  We have done this at the dealer with good success.