QuestionDear David,
I own a 2003 5,3L Chevrolet explorer conversion van and I am experiencing problems with the A/C. There is a drop in its performance, sometimes I think it just blows air. The same applies for the rear A/C too. The problem is more intense when the car is stopped with the engine running, even if I press the accelerator. When I switch it on I hear the clutch engaging and the roaring noise of the compressor, however the air cooling is not adequate. Yesterday, while the A/C was on I heard a "clicking" noise like something was going on-off continuously. What shall I check? Is it possible that it needs refrigerant? Is there an air-filter and where is it?
Thank you in advance,
Leo
AnswerLeo,
I believe what you are hearing with the ""clicking" noise is your compressor doing what we call cycling. What is happening is... your compressor runs, compresses the refrigerant, as the refrigerant enters and leaves your metering device, the pressure drops dramatically. This drop is normal, it is what it is supposed to do. But, as it continues to run, your low side pressure drops below the point that your low pressure switch says is safe (typically 17-22 PSIG) so it shuts down the compressor, protecting it. As the pressure equalizes in the system with the compressor off, the switch closes its contacts and the process starts again.
It sounds as though your system is running perfectly normal, with the exception of being low on refrigerant. If there is a low charge, the low side pressure will drop lower than normal. Thereby disengaging the compressor.
The only reason that you would have a low charge is because you have a leak. The A/C system is the same asw your refrigerator in the kitchen, only it has a few more doo-dads on it. It is a sealed system. Nothing should get in and nothing should get out. (When was the last time you had your refrigerator charged? Never? exactly my point.)
I would recommend that you charge your system back up... if it leaks out again before the end of the hot season, have the leak found and repaired, or this will be an on-going problem. If it holds its charge until... say... mid to late next year, then chances are the leak is so small that it will be very difficult for a service shop to find. Save yourself the money.
As for an air filter for the ventilation system, some vehicle have them, some do not. The usual place for them to be accessed is through the panels in front of your windshield. On the outside of the vehicle, where the windshield wipers hide. I am unsure as to whether yours has one or not. Easy way to check is look in your owner's manual, and see if they have it being changed as part of the routine maintenance tasks.
I hope I was able to help just a bit. If I can do anymore, by all means let me know. Thank you for the question and good luck in everything.
