I've got an W124 E200 wagon & last week I drained the coolant to re fill with fresh antifreeze. I had the engine running & the heater turned to full whilst refilling. Once done I didn't have any hot air coming into the car with the heater on, so I bled the system to rid it of any trapped air.

The temperature gauge is now showing just under 90 deg when running, but the heater inside the car is barely waming up & seems to be just luke warm at best. At the moment it's minus 8 deg outside & I really need to get the temperature inside the car warm again. It used to get lovely & warm inside within a short distance, but now regardless of how long it's driven it still doesn't get hot inside. Sometimes, first thing in the morning after a cold night, it's got ice on the inside of the windows & the heater doesn't melt it.

I've checked the car after a long run in minus 8 deg temperature today & found that the water in the rubber pipes seems to be warm up to the auxilliary heater pump, but the two hoses coming from the duo valves are cold.

I can't hear a buzzing noise from the pump, or feel any vibration, should I be able to with the engine running & the heater controls on full/hot?


Could this be a faulty pump, if so how do I check it, are they dismantleable to clean? Is the pump fused & could this maybe have blown?

If so where are the fuses?

Is this pump supposed to help circulate the flow of water through the heater matrix?

There's virtually no heat coming from any of the vents in the car (minimal at best compared to really warm before).

Do these symptoms point to pump or duo valve problems?

Sorry for sooo many questions but I really need some help with this as it's down right uncomfortable to drive now, as the windows inside are icing up as I'm driving.


Anyone have any ideas what could be wrong??

cheers...Nige

 

feel the pipes entering the duo valve.if hot going in and cold coming out then the valve may be defective.try tap the valve,works sometimes.could be the control panel inside but very rare.