I posted this once before, and couldn't get back to get an answer.... so here goes again.

1998 E320
Climate control blows hot all the time now.
Both sides, and center. (outside temp is 78, vents blowing 80 +.)
This with the climate control set to LOW and/or 60.

The compressor is engaged and spinning.
The Duo valve seems to be working (clicking when the control voltage is removed and restored)
((to be sure, I clamped the heater hose closed where it entersthe duo valve, with no change in cabin air temp))


I'm once again at a loss.

Ideas?
Anyone?

 

http://www.eclassbenz.com/node/27
run the tests post the numbers and errors.
then we can figure out what the issues are.
ohlord

 

I posted several times on this topic last year. Anyway, my issue was identical. What happened was that I had blockage in my system from gunk and sludge. They filled it and put some type of conditioner in it. It worked for 5 minutes then went back to the shop for two more days. They inspected all of the hoses again etc... found one on the "low side" that didn't look too good. (Cheap fix for the hose) and they refilled it with the conditioner again. It works like a champ and is ice cold. That repair happened last summer. I would not run the A/C at all in it's "hot" state. Try the flush and fill and inspect route. It may not cost you more than $150 etc... If that doesn't work... you have other issues at play that some independant dealers may not be able to fix. Good luck! [&:]

 

is the EC light illuminated in red on the climate control unit? a common problem with that model is the evap temp sensor going bad...its located under the driver dash..pretty east to get to if you know what your doing...usually what happens is it will blow cold for a minute or two(maybe less), and then start to blow warm..