Chasing an a/c problem on my 1993 W124, when the a/c is running, the metal return line comming out of the firewall to the aux water pump under the washer tank is hot, the top metal cap of the monovalve is hot also. the a/c expansion valve to the evaporator line is cold but the line from the evaporator to the expansion valve is warm, the a/c suction line to the compressor is warm also.

Do you think I have a monovalve/aux pump situation? keep getting a 30 flash fault code (recirculation pump). I am getting the correct voltages to the monovalve and aux pump.

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1993 Mercedes Benz 300D 2.5 205K (ex wife's)
1984 Mercedes Benz 300SD 320K (SOLD)
2004 Mercedes Benz C240 75K
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1983 Mercedes Benz 300SD 239K (SOLD)
1987 BMW 325i 220K (SOLD FOR SALVAGE)

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