Heat A/C question

[moparjohn]

Hi, I have an A/C and heat box in my car.  I just got it working today.  The question is does the heater supposed to send heat out the center duct below the radio? 1969 Charger.  If it is not supposed to I either have to adjust the heater control valve or one of the pods has the wrong vac. line hooked up . Any suggestions are welcome.

[is_it_EVER_done?]

Heat isn't supposed to come out through the A/C vents (some will because the flap valve isn't air tight). You might have a vacuum line hooked up wrong, but check that the diverter flap and it's linkage isn't rusted, crudded up, or blocked by debris. Also if you have a big cam, you might not be pulling enough vacuum for it to switch.

Another possibility could be the vacuum block (mounted on the back of the heat-A/C button assembly) can have a cracked or broken nipple, or have broken internally so that it doesn't switch.

Though I have never had one go bad, It is possible that the diaphragm in the vacuum pod for the diverter may have ruptured, but I would think you would hear it sucking if that was the case.

Of course you need to make sure that the vacuum lines aren't cracked or split, but I am allways amazed at how good the lines are that Chrysler used, as even after 40 years they are usually in excellent shape.

[moparjohn]

Well, then I have something wrong. But I know it's not the box itself- it was just redone by SMS. the control is NOS because the old one was broken, the lines all seem to be in good repair and I do not hear any hissing.  I also seem to have the heat on all the time , even in the off position.

[is_it_EVER_done?]

All the pods/linkages are on the outside of the box, so you can't really have a problem inside. Do you have vacuum to the center diverter pod? If so, the diverter either got jammed up when you put the A/C vent (half tube looking part with the floor thumbwheels) on, or the pod is not getting vacuum.

The heat being on all the time is controlled by the "Temp" slider (first button on the left side of the heat-A/C button assembly). If switching (sliding) it doesn't do anything, the fault is in the heater controll valve which is totally separate from the box/vacuum Assembly. The valve is located in the engine compartment and will have a heater hose going to it with a curved hose coming off it and going back into the heater core, and will be held on by three hex bolts.

Either the valve is bad, or the cable from the temp slide is broken, frozen, or out of adjustment. If the cable moves the valve when you push or pull the slider, you should check the cable adjustment which is about six inches behind the point that the cable hooks to the slider button - buried under the dash.

[moparjohn]

I thought it was the HCV too. now I'll recheck it.