Air Flow from wrong vents

[dbaker9323]

I wrote to you all recently about needing a new heater core for my 65 Riviera - thanks for your advice.     I am hoping that one or more of you may know a fix to a new problem.

 

The mechanic successfully changed the heater core from the engine side.  HOWEVER, now when the Heater is on  ( My car is an AC car), heated air flows from the proper defrost or heat vents according to the lever controls, but there is a continuous flow of untreated air coming from the AC vents.  (The AC is still functioning perfectly when engaged).  This air flow varies with the fan speed and speed of the car.

 

The Mechanic will continue to work on this to correct , but he states that all of the vacuum lines were properly reconnected and that they did not disturb any of the heater/ac vent doors.  I have provided him with the Buick service manuals to study to correct the problem.

 

Any suggestions?

[1965rivgs]

  Sounds like they messed up something in the area of the vacuum diaphram or the diverter door which it controls? This vacuum diaphram is just to the inside of the blower motor on the top of the metal blower duct. It is clearly visible when looking at the firewall area.

  Maybe they cut away too much from the firewall and have eliminated the partition between the heater and evap core? Oh, that wouldnt be good....

  Tom Mooney

[NC1968Riviera]

Check that the vacuum hoses in the back of the AC/heat controls are correctly attached. I had a similar problem with my AC routing when I knocked some hoses loose from the back of the controls and reattached them incorrectly. Also check that the diaphragm hoses are correctly routed and attached. A service manual will be your best friend for this job!