Postby ramishrrr » June 12th, 2008, 4:56 pm
If it is a car 5-6 years old it could be the following.
1. Check if there is a removeable filter behind the dash that needs cleaning/renewal.
2. This is a bigger issue.
Dust starts to clog the fins of the evaporator in the blower box behind the dash. That slows movement of the cold air from the coils to the vents, and to the cabin. However the thermostat is feeling the cold air in the evaporator box, and trips off the compressor clutch.
Turn on the ignition.....don't start the engine. Check the speeds of the blower and feel the quantity of air coming through the vents. (Compare it to that of someone's car with a good working AC)If the volume is substantially less than the good-working one, then the evaporator coil-fins need cleaning.
Because the dust buildup is gradual over years, you would hardly notice the deterioration of cooling and air volume coming through the vents.
This would require depressuring, removing, cleaning and recharging. Be careful with these AC places. These buggers want to maximise their profits, so they tell you that the expansion valve, and drier bottle need changing also, accompanied with a cock-and-bull reason why.
When I had mine cleaned on my B14 after 8 years from brand new, the volume of air was making my shirt flutter, and was freezing on the hottest days. I paid $2400 in 2006................and yes, they caught me with the expansion valve and drier bottle tripe.
All the best.
