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Heater not working, heater core is getting hot, but vehicle is not getting warm inside

Heater core is getting hot, but vehicle is not getting warm inside

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If the heater core is getting hot, you could have a problem with a blend door under the dash or the HVAC controller which opens and closes the doors.

Posted on Jan 13, 2013


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Posted on Jan 02, 2017

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SOURCE: heater not blowing cold air not warm or hot

A heater core only needs to be changes if it is blocked with rust or is leaking, a more plausible reason would be a stuck open thermostat in the engine cooling system. Also check under the hood for hot coolant in and out of the heater cores hoses, those are the small hoses going to the firewall and into the truck.

Posted on Nov 19, 2008

  • 306 Answers

SOURCE: my 2000 s10 chev does not blow hot air on heat.the

The heat and cooling air flow is controlled by small plastic vacumn lines inside the dashboard. The main vacumn suppy for this comes from the engine vacumn lines. So - Find what you are missing in your vacumn lines.

Posted on May 07, 2009

  • 3051 Answers

SOURCE: heater core

Hello there:
These are not hard to remove the hard part is to get the two halves of the box open they are sealed together so what you need to do is to get a really sharp utility knive and cut along the seam and then this will allow you to split the box and remove the covere so you can get to the heater core.
Once the repairs have been made make sure that you reseal the two halves so that no water or air will get inside ok.
best regards michael

Posted on Oct 31, 2009

  • 30 Answers

SOURCE: Heater blows only luke warm air.

check control swicth

Posted on Feb 12, 2010

  • 3 Answers

SOURCE: how to make heater get hot in 94 chevy caprice.

This is a very common problem with the 94, really common with the LT1. I have done everything I can think of with my Caprice, and lets just say I don't drive it in the winter anymore.

Posted on Jul 17, 2010

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You either have a thermostat that is stuck open or the heater core is plugged. Get the vehicle warm and feel both of the hoses going to the firewall/heater core. Both of the hoses should be hot to the touch. If one is hot and the other considerably cooler, the heater core is plugged. If both are relitively cool, the thermostat is stuck open.

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The heater in your car depends upon a flow of hot coolant going through the heater core in order to get hot air into the car. If the heater core is partially plugged, it will restrict the flow. If you have a head gasket that is putting exhaust into the cooling system, it will eventually get into the heater core. When this happens there is no coolant in the heater core to make the air warm. If the water pump vanes have corroded away the result will be very poor coolant circulation causing the heater to not blow hot air. If your car is equipped with a heater control valve that is not functioning properly, the coolant flow will be restricted. One or a combination of these factors is likely the culprit in your case.

To attempt to clean the core, you must flush the system multiple times. If this does not work, the core cannot be cleaned and must be replaced.

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