Heat or testing heat

[llhat]

1989 Comanche with A/C  4.0

 

some help with possible diagnosis of heat in regards to any 'blend door' actuation

 

i do believe i have very low flow through core after testing with heat gun...   unsure if thermostat is stuck open (temp seems a bit low to me)

will be replacing thermostat and housing with the later version for possible access point for ether a mechanical or electric temp gage,

in some research, the control valve ( still closed system) is normally Open, allowing flow until AC is set, then closes off flow.

assume this is with vacuum on the valve, and it has none in normal state.

 

images or whatever of the blend door area location and maybe vacuum diagram of the control circuit

 

thanks in advance.

[pizzaman09]

The control valve has a pink plastic vacuum line running to it.  Might be worth checking to see if the valve is opened or closed.

 

It's also possible that your heater core is clogged.  They can be flushed out with some success.

[Ωhm]