1994 ford explorer no heat

i have a 1994 ford explorer thats blows cool air when i have the heat on the hoses going to and from the heater control valve are gettin hot , so im thinking what could it be a , found out that the lower radiator hose wasn't even hot like the others , i was reading around and saw topics about blend doors etc i just want any advice . also the owner used radiator stop leak was used in the radiator a couple months ago . Could it be a thermostat ? the cars not overheating though thanks

i have a 1994 ford explorer thats blows cool air when i have the heat on the hoses going to and from the heater control valve are gettin hot , so im thinking what could it be a , found out that the lower radiator hose wasn't even hot like the others , i was reading around and saw topics about blend doors etc i just want any advice . also the owner used radiator stop leak was used in the radiator a couple months ago . Could it be a thermostat ? the cars not overheating though thanks

That stop leak crap is the devil. All it does is clog up everything except the hole. It is a little weird that your lower hose is not getting hot but if your not overheating then your alright there. With the thermostat most new thermostats stay in the open position if they fail as a safguard to keep your car from overheating. So you might just go ahead and replace that as they are only like $3. There is a post on here about fixing the blend doors but I am not sure where it is at. Good luck.

when is the last time you had it backflushed? might pick up a prestone flush kit its like 3 bucks a wallyworld and some antifreeze, fixed my 00 jimmy when it did that