Thanks for the correction on which fitting... I figured the duovalve and A/C problems were separate.... Now, I heard that unplugging the duovalve causes the heat to be at high all the time. Which plug or both??

__________________
All it takes for evil to prevail is for good men to stand by and do nothing.

Too many people tip toe through life, never attempting or doing anything great, hoping to make it safely to death... Bob Proctor

'95 S320 LWB
'87 300SDL
'04 E500 wagon 4matic