Heater not hot!

cirsurvive711

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radiator topped off? check that first..

cause if the car heats up...if theres not enough hot radiator fluid going through the heater core...your heater core won't get hot...and your air won't get hot

+++1

same thing happened to my dad's Blazer last year
 

Dinzdale40

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i know you said you topped off the radiator overflow...but you still need to make sure the radiator is full...if it's not there is probably a leak somewhere...and your heat not getting hot is only a symptom of another problem...
 

klr4life

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k so just wondering if you guys would know whats wrong with my accord. After my car has warmed up and I turn on the heat its actually cold air still coming out of the vents but when i rev the car or drive it the air gets warm. still not warm like it use to get but it definately goes from blowing cold air to warm air when the revs are up. Any idea what it could be?

I am having the same exact problem stated above, is there a fix for it? i changed my thermostat and get the same results.
 

henreeezy xp

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something might be wrong with the compressor? i mean, nothing else related to the heater/ac stuff speeds up except the compressor that's belt driven, i think... i needa pull out my climate control textbook. i'll update tnight if i find anything lol
 

Drift

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Alright guys, its probably the water valve that leads into the heater core. They have a tendency to seize up during the summer and not want to move when you need them too (during winter). When you turn the heater know to full hot, it drives a motor that opens that valve to allow hot coolant into the heater core.

Its on the fire wall and the lower heater hose leads to it. There is a cable leading to it and the pivot that the cable attaches to also has a tendency to twist, thus not allowing the valve to open.


The thermostat should have nothing to do with the temperature of the air coming into the cabin unless its stuck open. That is fairly easy to confirm simply by driving the car. If it warms up at stop lights and cools off when you start moving, then the thermostat is stuck open. But when you're at a stop light and the car is able to warm up, you should feel the heat coming into the cabin, and then it will stop as the car starts moving.
 
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finch13

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something might be wrong with the compressor? i mean, nothing else related to the heater/ac stuff speeds up except the compressor that's belt driven, i think... i needa pull out my climate control textbook. i'll update tnight if i find anything lol

Water pump...

Alright guys, its probably the water valve that leads into the heater core. They have a tendency to seize up during the summer and not want to move when you need them too (during winter). When you turn the heater know to full hot, it drives a motor that opens that valve to allow hot coolant into the heater core.

Its on the fire wall and the lower heater hose leads to it. There is a cable leading to it and the pivot that the cable attaches to also has a tendency to twist, thus not allowing the valve to open.


The thermostat should have nothing to do with the temperature of the air coming into the cabin unless its stuck open. That is fairly easy to confirm simply by driving the car. If it warms up at stop lights and cools off when you start moving, then the thermostat is stuck open. But when you're at a stop light and the car is able to warm up, you should feel the heat coming into the cabin, and then it will stop as the car starts moving.

Exactly what I was going to say!
 

klr4life

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Alright guys, its probably the water valve that leads into the heater core. They have a tendency to seize up during the summer and not want to move when you need them too (during winter). When you turn the heater know to full hot, it drives a motor that opens that valve to allow hot coolant into the heater core.

Its on the fire wall and the lower heater hose leads to it. There is a cable leading to it and the pivot that the cable attaches to also has a tendency to twist, thus not allowing the valve to open.


The thermostat should have nothing to do with the temperature of the air coming into the cabin unless its stuck open. That is fairly easy to confirm simply by driving the car. If it warms up at stop lights and cools off when you start moving, then the thermostat is stuck open. But when you're at a stop light and the car is able to warm up, you should feel the heat coming into the cabin, and then it will stop as the car starts moving.

Ok i will check this but how will i know if th evalue is opening or not? to fix the problem.
 
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