So I plugged my truck in last night for the first time ever since I bought it. This morning it only took 5 minutes to warm up, but my heater is only blowing cold air. I am guessing its a thermostat but could it be anything else?
2002 F-250 with a 7.3.

Thanks in advance!
Derek

 

If it was the thermo stat you wouldnt have seen the truck heat up.

I can only think of a couple of things,
1st, are you putting the right coolant in the truck, sorry I have to ask, but coolants dont always like each other and will do some kind of jelling. Happens to GM's a lot when they are supposed to have the dextron, and someone throws in the wrong stuff.

The next thing I would be looking at would be the blend door control and then the motor..

 

Thanks for the input, I will take a peek at it at lunch. My coolant level is a bit low so I'll add a bit too.