WHo has vintage air??

[gregbr]

I'm starting to install mine on a non a/c cab. After reading the instructions and contacting the tech support....the system using the factory heater controls does not have temp control. It appears to be wide open heat or a/c with no temperature control like the old heater had. Is this correct and is it a big problem?? I see where you can get a different inside unit and use the factory a/c controls and it will control the temp using a cable controlled heater valve instead of the vacuum open/closed valve that I have. According the tech support these are 2 different under dash units. Of course the dealer I used did not tell me any of this. Any advice..........Greg