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Q: Heat does work but AC does...

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My heat doesn't work. My AC works great. Cold air comes out when it's on heat. My heat/AC knobs work. We've changed the thermostat and flushed it out. We don't know where to go next.
My car has an automatic transmission.

Hi there:

Usually, when the heater is not working, overheating problems are often linked with this issue if it’s a mechanical problem with the heater core. However, it’s possible that the heater’s fuse or electrical relay is faulty or broken and needs to be replaced. The best way to minimize the guess work is to have a professional mobile mechanic complete a heater is not working inspection.

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Hi. The heating system is separate from the A/C system so it is normal that the A/C system is working properly right now. There could be a few things causing your no heat issue at this point. The radiator could still have a clogg in it or not operating properly causing no heat. There also could be a problem with the heater core being clogged up or the heater core is failing and can’t give off heat so your suv will have heat. Another possible cause of this problem is a stuck heater control valve and it is not allowing the heat to come in the engine compartment. I suggest you have a certified tech from yourmechanic come and diagnosis your suv for its no heat condition.

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