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View Full Version : If A/C not cold enough.



paul67
08-18-2007, 07:53 AM
Have noticed that some people have said that the A/C is not cooling there car down.I have a 2003 Dodge Ram truck and just noticed today that the condenser rad has it own fan, maybe this option could be used to cure the problem, just a thought.

dsapper
08-22-2007, 09:40 AM
Durring the summer I buy cheap hot water heater insulation foam from home depot and zip tie it on all the ac lines, helps quite a bit. Then in the winter snip the ties off. Been doing that for years, makes a big difference even on new cars.

MonzaRacer
08-23-2007, 06:44 PM
OK as for the insulation of the lines will do nothing but make sure the heat moving out will go through the condenser nad not the lines.
Ok first of all AC is simply moving heat from one pointto another.
So first of all you must have proper air flow, system charge and proper adjustment of air flow and control of refrigerant.
You will notice a better performance if you use max air or a recirculate mode as then your only moving heat from inside the cabin and you and whtas coming in from outside.
With out either you are trying to cool the outside 85-1005 degree air, dehumidify it and then remove all the other stuff,,, in short it wont work but if your wife is cold switch to freshair.
If you dont have proper airflow over the condenser your system will raise the high side preasure too hich and either cycle out or blow off the excess preasure through a pop off. Then your low on refrigerant.
Proper control of the refrigerant flow is critical.
If your system has a orifice tube have it up graded to a AAOT (Automatic Adjusting Orifice Tube) or "self adjusting " .
When it the need it will throttle the flow so as to reduce the load on the compressor, keep the evaporator from being flooded with excess refrigerant( they do this sometimes when the person repairing the system tries to intall a different O tube to "boost" the cooling.
If you have a car with a POA/STV system with a Exapnsion valve with sensing tube , it can be converted and will never freeze the evap as it will keep the refrigerant flow controled much better.
As for removing the insulation why do you remove it? Simply install it and leave it alone, it wont hurt anything, period.

Mjwhoopie
04-16-2008, 09:24 PM
Monza, Where can I find information on converting AC systems to the AAOT style control?

I'm starting a resto mod on a non-ac 69 Kingswood and want to start with the most efficant system avalible. (it's alot of interior to cool)

THX, Mike

Mjwhoopie
06-21-2008, 08:38 PM
I know that a properly sized system for the car your trying to cool is of great importance.
I haven't looked real hard lately, but, does any one have a link to the fomulas for figuring the system sizes?

condenser size
evaporator size
ect, ect.

B Schein
06-22-2008, 03:35 PM
I know that a properly sized system for the car your trying to cool is of great importance.
I haven't looked real hard lately, but, does any one have a link to the fomulas for figuring the system sizes?

condenser size
evaporator size
ect, ect.

Buy a heat transfer book it will have all the equations you need. The only problem is they are calculus based so it might not make that much sense if you have never taken an calculus class

My university teaches a whole class on this its called thermal fluids design.

Fuelie Nova
06-22-2008, 06:30 PM
I had similar problems with my Nova. Another angle to take on this issue is firewall, floor, roof and door insulation. It seemed like my vintage air was marginal for capacity, insulating the entire interior and roof area under the head liner helped a ton. I do hear that the Vintage Gen 4 system pumps out ice cold air
Tg