# Blocked Heater Core

**URL:** <https://community.cartalk.com/t/blocked-heater-core/89826>\
**Category:** Maintenance/Repairs\
**Tags:** gmc\
**Created:** [April 30, 2015, 1:57am UTC](https://community.cartalk.com/t/blocked-heater-core/89826 "2015-04-30T01:57:54Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![AndyB1](https://avatars.discourse-cdn.com/v4/letter/a/ac8455/32.png) [@AndyB1](https://community.cartalk.com/u/AndyB1)\
**Post date:** [April 30, 2015, 1:57am UTC](https://community.cartalk.com/t/blocked-heater-core/89826/1 "2015-04-30T01:57:54Z")

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I have a 2010 GMC 3500 Savanah van with 6.0 motor. No heat in van. Engine operating temp is normal. Heater hose into core is hot. Hose coming out is barely warm. I am of course hoping for another explanation other then blocked heater core. The truck only has 45k miles. I am ready to backflush , but wondering if there can be any other explanation. A/C works normal Thanks for any suggestions

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**Author:** ![Barkydog](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/barkydog/32/2470_2.png) [@Barkydog](https://community.cartalk.com/u/Barkydog)\
**Post date:** [April 30, 2015, 2:18am UTC](https://community.cartalk.com/t/blocked-heater-core/89826/2 "2015-04-30T02:18:56Z")

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I do not know but it is possible there is a control that allows flow to the heater core of warm coolant that may have failed.