Inconsistent Heat from Climate Control W220 190E 1990 2.6 - PeachParts Mercedes-Benz Forum

geokirk · #1 09-12-2006, 12:58 AM

Sometimes, the heater works fine, sometimes it warms too little and sometimes it does not function at all.

For 1 ½ weeks I had it set to max heat and it produced none at all. The temperature outside varied from 66F to 80F and inside was the same with the sunroof and windows open. Now, suddenly it began to work once again as I expected it would sooner or later. When it will fail again, I don’t know. In the winter at times it produced heat, but only barely and other times it worked as it should.

So I just bought a rebuilt Climate Control unit. Before I install it, are there any other items that should be replaced or looked at while the dash is out?

For instance, from this site, I learned there may be a Blower Aspirator for temperature sensor ventilation which may be near the Heater Fan Motor (it squeaks off and on during the winter… annoying… any suggestions?). And I learned there may be a Sampler Blower Motor For Temperature Sensor Ventilation on roof rail which draws air from a specific location in vehicle to sample the temperature and relays information to control unit which takes action to correct to desired temperature setting.

Thermo-Vacuum Valve is a two position valve = open/closed, installed in the engine water jacket, when it reaches temperature the valve opens passing vacuum.

Heater Valves… is any brand a good?

So where do I start, what is worth replacing wile in the dash and do I really have all these items as stated?

Thanks,
George