On this case, i suggest you to check this direct help links.
The problems like heater not blowing hot,ho heat,car blows hot and quits,heater blows cold,etc.
are very much noticed on vehicles.In this case
See the help links below :----
Car quits heat after few minutes?
http://technoanswers.blogspot.in/2012/02/chevy-equinox-quits-heat-after-few.html
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Engine Overheats and heater blowing cold?
http://howtobyme.blogspot.com/2011/11/engine-overheats-and-heater-blowing.html---------
Heater stuck on defrost?
http://howtobyme.blogspot.com/2011/12/heater-stuck-on-defrost.html---------
Car heater blowing warm, but not hot air?
http://schematicsdiagram.blogspot.com/2011/12/car-heater-blowing-warm-but-not-hot-air.html--------
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Heat blows cold on drivers side and hot on passenger side?
http://schematicsdiagram.blogspot.com/2011/12/heat-blows-cold-on-drivers-side-and-hot.html
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Hot air on the driver’s side vents only?
http://repairhelpcenter.blogspot.com/2012/01/hot-air-on-drivers-side-vents-only.html
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Ford Ac only blows through defrost vents?
http://technoanswers.blogspot.com/2012/01/forf-f150-ac-only-blows-through-defrost.html
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A/C come out of defrost vents only?
http://technoanswers.blogspot.com/2012/01/dodge-ac-come-out-of-defrost-vents-only.html
Ac vacuum line on dodge cummins?
http://technoanswers.blogspot.com/2012/01/ac-vacuum-line-on-dodge-cummins.html
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Ford AC blows cold through defrost vents instead on cabin vents?
http://technoanswers.blogspot.com/2012/01/ford-ranger-ac-blows-cold-through.html
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AC air blows through defrost vent only on Ford ?
http://technoanswers.blogspot.com/2012/01/ac-air-blows-through-defrost-vent-only.html
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Ford Air flow selector not working and Air blows from defrost vent only?
http://technoanswers.blogspot.com/2012/01/ford-escape-air-flow-selector-not.html
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AC blows air out of defroster and floor vents only on ford ?
http://technoanswers.blogspot.in/2012/01/ac-blows-air-out-of-defroster-and-floor.html
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This details will help.
Thanks.