'83 911SC heater stuck on. Help! My feet are burning up!
 

This problem has been going on for a while. The heater is stuck on. The mechanic replaced the defroster/heater control board (I think it was a salvage part, not a new OEM board) but no luck. [:@]

I was told by a friend that it could be rusted heat exchanger valves, but they move freely. I'm thinking either the control board or the cable is stuck somehow.

Anyone have any suggestions?

RE: '83 911SC heater stuck on. Help! My feet are burning up!
 

Have someone crawl underneath while you operate the controls and see if the gates are moving. It is a mechanical link, via a cable, so they can't really not work if the cable isn't broken, and the valves arent rusted.