When the A/C is operating I am getting a discharge temp of 48-51 Deg.

I can drive to lunch come out, restart and NO A/C. Just blows hot. I can stop somewhere again, restart and A/C operates fine.

Over the years I have had freon properly added, but I am wondering since I have never had it evacuated, could moisture have entered the system and it freezes at the expansion valve ??

What values/addresses should I look at if it is electrical ??

Any assistance is greatly appreicated !!

__________________
Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW

Check your Douvalve. Lil twin silo's next to the computer box.

Solid smack with a rubber handled screwdriver helps sometimes.

Can be rebuilt also.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Will Do, next time it quits,

Anything else I should be looking for on the ECM display ?

Thanks

Sent PM

__________________
Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW

Did some research on Dou valve and I will look to pull them, clean & lube them.
Do they control the heat to each side of interior ?

If so what is the chances both would pass same time ?

__________________
Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW

I think it's more likely the controller is having problems. The way the duo-valve works, when there's no power, the heat is full on. you can pull the connector and test for voltage that comes and goes. A steady low would seem to indicate a failure. A steady high is OK.

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-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

KarTek,

Where should I start to determine if a controller problem ?

Thanks

__________________
Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW