Toyota Repair: Heater 4Runner, heater control valve, heater core

Question
The heater in my '97 4Runner has not been working for a while; it always blows cold air.  I'm presuming that since both of the water hoses going into and out of the firewall get hot, the problem is not likely to be the heater core (or is it?).  A/C runs fine. Thanks in advance.

Answer
Both heater hoses being hot is not an indication that the heater core is good, the coolant is not circulating through the core, it has to do this to make the heater work, either the heater core is clogged or there is a problem with the heater control valve.