Answers: HEATER NOT BLOWING COLD,NO HOT AIR FROM HEATER,A/C BLOWS HOT AIR,A/C NOT BLOWING COLD, COLD AIR FROM HEATER,BLEND DOOR ACUTATOR CLOSED,HVAC UNIT NOT OPERATING,

A/C and heater problems on car, Heater blows Cold Air, A/C blowing Hot air, No cold air from System, No hot Air from System, Hot air on driver side only,

There are many such car HVAC system issues noticed by car owners

Heater and A.c System are very important factor of car.
At required time you really need them,if the heating or cooling is not working properly it really makes you worried and also at times frustrated.

So in that case to troubleshoot the issue.

The most possible help links are provided below:-----

It can be low coolant,or may be coolant getting leaked from under the vehicle, or its blockage in coolant line causing no coolant to run and you notice vehicle overheating or no cool air.
Another possibility is the air blend door not working properly.
Also check the hoses for warm water flow to make sure that the hot water is flowing properly.
Touch and feel each hose to see if both are getting hot. If not then issue is closed thermostat or faulty thermostat or the valve in line might be shutting off the water flow.
On some vehicles there is thermostat and on some there is temp control valves to prevent water flow through the heater core during the run of the ac.
If hot water is flowing correctly through the heater core, then next step is to access the under dash area to see if the heater blend door is operating properly.
These blend door actuator are usually vacuum operated.
So make sure you check no vacuum lines are broken.
Some blend doors on some cars are operated by normal motor,on that case the motor and its wiring needs to be inspected.

As per your problem mentioned. There are few solved help links to troubleshoot these problems. Go through the list and Check the link below:----

Air conditioner blows air but not cold air

http://repairhelpcenter.blogspot.in/2012/07/air-conditioner-blows-air-but-not-cold.html

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Car overheats and Air blows hot at idle?

http://howtobyme.blogspot.com/2011/11/car-overheats-and-air-blows-hot-at-idle.html

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Heater blows cold?

http://schematicsdiagram.blogspot.in/2012/02/heater-blows-cold.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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