I have an 01 Blazer that doesn't blow hot air when the heat is on. It will blow cool/ warm air but not hot even when the temp is at normal operating temp. I replace the thermostat with a 195 degree stat and it still blows cool/warm air. I want the hot stuff. It gets pretty damn cold up here in Minnesota and I hate driving around with cool air blowing in my face when it's -10 outside. Any help is appreciated.

 

check the coolant level, and remember just becasue a part is new doesnt mean it works. i have installed many *NEW* thermostats only to find out they dont work. but if your coolant level is fine and your confident your thermostat is good i would flush out the heater core as it could be clogged with crap from lack of not flushing the cooling system regularly.

 

that dexcool crap clogs heater core worse than a fat man's arteries eating a double whopper. happens to me every year. pick a day above freezing or inside shop, unclamp 2 hoses going into firewall to heater core. go to parts place or hardware store and buy two sections of hoses. connect to exposed heater core inlet and outlet. use water hose and backflush heater core for about 3 minutes. congrats you have performed your first heater core catherization. reconnect hoses back to heater core and enjoy the heat. go back and check for any leaks and you are done. recheck antifreeze level and replenish if needed

 

^X2^ except after the flush i would also flush the block and radiator and switch over to the green coolant.