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C230 MBenz 1998

Sporatically, the A/C will put out intense heat at the driver’s side vent. +Sometimes the passenger’s side vent. + sometimes the floor vent. Computer diagnostics have not uncovered the problem.

During this time, the A/C will not turn off.

Love your show. Thanks.

The problem you describe occurs when the AC is on and shoots
frigid air to the in-cabin temp sensor (located in the dome light
assembly in W201s - I expect it’s there in a W202 as well). So the
sensor thinks the temp is too cold, so adds heat to the equation, but
only cold air can emerge from the center vents (by design) so you get
hot air from the sides and cold from the center that continues to cool
the in-cabin sensor and keep the warm air coming out of the side vents.
Closing or redirecting the center vents can usually manage to control
the problem.