Heater does not blow warm air
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1991 Cadillac DeVille Question: Why is it that the heater only blows cold air
G. T. Service Center (3112 Answers) , Stephenville, TX - (254) 638-3236ProfessorG November 29, 2013, 20:44Master
First make sure your coolant is full, then is your engine reaching normal operating temperature ( 180-200deg). Then check to see if the heater hoses are hot to the touch on both hoses. If that is all good then we move inside the car.
ReplyJMGSR, November 29, 2013, 21:11Rookie
The temperature is up. What is inside to explore?
ReplyProfessorG, November 29, 2013, 21:15Master
That's when we check your controls. But first we need to make sure the heater core is getting hot so we know it could be the controls. If the heater core is not heated by the coolant then it doesn't matter about the controls, we assume they are working until proof tells us otherwise.
Answer #2bmdouble November 29, 2013, 20:45Master
Make sure your coolants level is good then check the temp at the inllet and outlet of theheater core hoses.could be low coolant level ;thermostat, clogged heater core or heater plenum concerns