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Can the heat and A/C run at the sametime

pro-streeter

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I have cold air one the drivers side and hot on the passenger side. Could my control switch be bad and not overiding the A/C switch when it is slid it should turns off heat?
 
I have cold air one the drivers side and hot on the passenger side. Could my control switch be bad and not overiding the A/C switch when it is slid it should turns off heat?
Seems like a blend door is stuck half way. But you said they were working fine. Maybe check the cables if you have cables and make sure they haven't come loose.
 
There are 3 vacuum operators. 2 of them are operating near as I can tell correctly. The 3rd when I change the controls does nothing. It is connected to the door that is directed to the foot area. Would that create a heat on one side and cool on the other? I would think when the A/C is activated the foot door should close also which is not the case.
 
I'm not familiar with the Ac setups on these cars. Maybe try pulling vacuum on that actuator and see if it makes a difference.
 
vacuum test pumps are cheep and will test for operation and bleed down leaks.
 
To answer your question, you should be able to run both A/C & heat at the same time. That is how you dry out a foggy windshield on a 40 degree rainy day with 100% humidity. You dry the air first, then heat it.

I was going to ask if you are sure that the system is fully charged, but since you said cold & "hot" vs cold & warm, I would suspect an actuator vs low refrigerant.
 
To answer your question, you should be able to run both A/C & heat at the same time. That is how you dry out a foggy windshield on a 40 degree rainy day with 100% humidity. You dry the air first, then heat it.

I was going to ask if you are sure that the system is fully charged, but since you said cold & "hot" vs cold & warm, I would suspect an actuator vs low refrigerant.

I agree with the actuator as suspect
 
Sounds like you are using and after market kit, which has 2 or 3 solednoids that operate the heater valve, damper door and/or defrost door. Sounds like heater valve is stuck(trash).. but what doesn't sound right is that you have difference on each side....its a common plenum so don't really see how its possible...???
 
if it is factory ac , the valve on the fire wall is,,, not adjusted correct, or leaking internally, it is connected to the temp slide on the ac/heater controls.
 
if it is factory ac , the valve on the fire wall is,,, not adjusted correct, or leaking internally, it is connected to the temp slide on the ac/heater controls.
I will check the water valve as suggested. That could be not opening/closing as it should.

Do you know what the method is to test or check it by chance?
 
I think those have a 90 degree stroke with a spring return, if its the vacuum actuated type. You should be able disconnect the source and see if the arm is perpwndicular to the line. Also verify that the flow is correct through it. If the valve is installed backwards the pressure can partially unseat the valve.
Pics of the set up would help.
 
is it possible even though it has been just charged it is not fully charged enough to offset the 30% for the the reheat cycle? Water valve functions on fire wall.
Still cold on the left and warm on the right
 
It is designed to run the AC and heat at the same time. For the reason Ranger16 mentioned and also to increase the temp a bit if the AC is too cold. However, you should not have cold on the left and warm on the right. It all comes from the same source so the temp on the right and left should be equal. This is assuming you are running a stock system.
 
It is designed to run the AC and heat at the same time. For the reason Ranger16 mentioned and also to increase the temp a bit if the AC is too cold. However, you should not have cold on the left and warm on the right. It all comes from the same source so the temp on the right and left should be equal. This is assuming you are running a stock system.

Thanks for the confirmation.
 
Does anyone know what type of construction the heater valve is? This has the 2 heater cores with the valve that closes off the heater core to 30% when you turn on the A/C. The A/C door does open and close this valve from my view externally. Could it be the lever moves externally but the valve internally is not functioning as it should?
 
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