air con fan

jondonwar · 29th July 2019, 15:54

Hello guys just had my car 05 cdti air con regased and when I switch it on the fan comes on is that normal it was done on a brand new state of the art machine costing nearly £4000 ,the car does blow cold but not icy cold just unsure if fan should be on regards john

stevestrat · 29th July 2019, 16:20

With the air con on, below a certain road speed (not sure what) the fan will run at slow speed to force air through the air con condenser.

T-Cut · 29th July 2019, 17:50

The low speed radator fan switches on by default whenever the aircon system is switched on. It's required to operate the condenser mounted ahead of the main radiator. If the condenser ain't condensing (for whatever reason) the aircon will shut down due to over-pressurisation. This is why the so-called Demist Test is the default way to check your slow speed fan. It should run continuously until the aircon system is switched off. This holds true for cars with the simple aircon system and for the Climate Control models. As noted, a failed low speed fan will cause the aircon system to malfunction, particularly when the car is stationary or in slow moving traffic. A competent aircon mechanic will check radiator fan cooling as part of the service.

TC

SD1too · 29th July 2019, 19:21

Quote:

Originally Posted by jondonwar

Hello guys just had my ... air con regassed and when I switch it on the fan comes on is that normal ...

The short answer John is yes!

Quote:

... the car does blow cold but not icy cold ...

The temperature of the air emitted from the centre vents with the controls set to 'LO' should be 4 degrees C. A competent air con. specialist would place a thermometer to check this. If your air output is significantly warmer than this, the cause needs to be investigated and rectified.

Quote:

Originally Posted by stevestrat

With the air con on, below a certain road speed (not sure what) the fan will run at slow speed ..

It's nothing to do with road speed Steve. The fan should run continuously when the air conditioning is operating.

Simon

29th July 2019, 15:54	#1
jondonwar Avid contributor rover 75 saloon connoisseur se cdti Join Date: Aug 2012 Location: liverpool Posts: 175 Thanks: 102 Thanked 8 Times in 6 Posts	air con fan Hello guys just had my car 05 cdti air con regased and when I switch it on the fan comes on is that normal it was done on a brand new state of the art machine costing nearly £4000 ,the car does blow cold but not icy cold just unsure if fan should be on regards john

29th July 2019, 16:20	#2
stevestrat This is my second home ZT260 #243 (resting) Join Date: May 2010 Location: Prestonpans Posts: 22,462 Thanks: 650 Thanked 4,624 Times in 3,358 Posts	With the air con on, below a certain road speed (not sure what) the fan will run at slow speed to force air through the air con condenser. __________________ Steve T4 Location Map

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29th July 2019, 17:50	#3
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,752 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	The low speed radator fan switches on by default whenever the aircon system is switched on. It's required to operate the condenser mounted ahead of the main radiator. If the condenser ain't condensing (for whatever reason) the aircon will shut down due to over-pressurisation. This is why the so-called Demist Test is the default way to check your slow speed fan. It should run continuously until the aircon system is switched off. This holds true for cars with the simple aircon system and for the Climate Control models. As noted, a failed low speed fan will cause the aircon system to malfunction, particularly when the car is stationary or in slow moving traffic. A competent aircon mechanic will check radiator fan cooling as part of the service. TC