Oulra

I bought an '87 944 with a non-operational heater. With heat on full blast, I just get a stream of ambient temperature air. AC works, but is low on refrigerant (retrofitted to r134a) from what I can tell. The coolant looks clean and the reservoir is full. What should I do to troubleshoot the issue? The heating issue isn't a huge problem as we're nearing summer, but I am worried about what would cause it as my engine/engine bay is also surprisingly hot, even though the coolant temps reads normal. It's running hot enough to where opening the hood is painful, given the hood insulation was torn off by a previous owner. I would appreciate any input into what could be going on or how I may be able to fix the issues my car is having.

mel_t_vin

The heater control valve [HCV], located at the top/center of figure #1, is vacuum operated.





Make sure the master vacuum supply {#4] and HCV vacuum supply [#5] are correctly configured, as shown in figure #2.