Good Evening
My car is a 2006 E280 (pre-facelift)
The air conditioning was not cooling the car but there were no errors reported.
The B12/2 pressure was 3 bar with the engine off and rose to 5 bars with the engine running at idle.
I contacted the local Mercedes dealer who recharged the air conditioning.
When the car was returned the air conditioning was working well however the electric engine fan was running very fast and was very noisy. I have owned the car since nearly new and can never recall the fans running so fast.
I left the car overnight and tried it again the next morning when cold.
I measured the pressure before starting and it was 13.4 bar. When the engine was started and running at idle it was 18.9 bar. The electric engine fan immediately started to run very fast with a cold engine at idle. The fan is so loud that it is clearly audible over the road noise at 60 mph.
The Mercedes WIS states that the AC controller varies the engine fan between 0% and 100% for pressures between 12 and 20 bars. Therefore I assume that the fans are running fast due to the AC refrigerant pressure.
The dealer is currently testing the car and have stated that the normal pressure is between 0 and 30 bars so my figures with the engine off and running at idle are within spec.
Please can someone tell me if the pressure of the recharged system is correct and if so is it normal to have the electric fan running so fast with a cold engine?
Thanks
Steven
My car is a 2006 E280 (pre-facelift)
The air conditioning was not cooling the car but there were no errors reported.
The B12/2 pressure was 3 bar with the engine off and rose to 5 bars with the engine running at idle.
I contacted the local Mercedes dealer who recharged the air conditioning.
When the car was returned the air conditioning was working well however the electric engine fan was running very fast and was very noisy. I have owned the car since nearly new and can never recall the fans running so fast.
I left the car overnight and tried it again the next morning when cold.
I measured the pressure before starting and it was 13.4 bar. When the engine was started and running at idle it was 18.9 bar. The electric engine fan immediately started to run very fast with a cold engine at idle. The fan is so loud that it is clearly audible over the road noise at 60 mph.
The Mercedes WIS states that the AC controller varies the engine fan between 0% and 100% for pressures between 12 and 20 bars. Therefore I assume that the fans are running fast due to the AC refrigerant pressure.
The dealer is currently testing the car and have stated that the normal pressure is between 0 and 30 bars so my figures with the engine off and running at idle are within spec.
Please can someone tell me if the pressure of the recharged system is correct and if so is it normal to have the electric fan running so fast with a cold engine?
Thanks
Steven