Re: AC Compressor cycles

["johnsdmc12" <dherv10@xxxx>]

David and group, There are several thing which affect the cycling of 
the A/C compressor. 
#1. Is the Low pressure switch. Condition and adjustment.
#2. Amount of freon is the most common because you may tend to leak 
down during the winter.
#3. The amount of air blowing over the evaporator core in the heater 
box compartment.
#4. The Temperature of the air blowing over the evaporator core from 
out side.
#5. The compressor will cycle more if the speed of the blower motor 
is set on 1 vs 4.
#6. The temperature outside. Slower speed the more cycling.
It's like a clock working, it all depends on the conditions of all. 
If the LP switch is ok, and your full on freon,and it's 80 to 90 
degrees out side and you have the blower motor set on 4. Then mine 
cycle about every 40 sec. But, If your low on freon, and the switch 
isn't adjusted correct, it's 70 degrees out side and you have the 
blower fan on 2, then you may cycle every 5 sec.
What's happening is the LP switch is trying to protect the compressor 
from freezeing up by cycling the compressor on and off. 
John Hervey
www.specialTauto.com
P.S.There is a good technical explaination on page 334 of the 
technical manual.






--- In dmcnews@xxxx, Delorean17@xxxx wrote:
> Hi,
> Before I go to Memphis I want to make sure I am not going to 
fry my AC 
> compressor on the way. I had the system vacuumed out and charged 
with R12 
> last summer and it has been blowing cold air ever since but I think 
it may be 
> cycling a bit much.
> I have a light hooked up that shows when the AC compressor 
comes on. 
> When driving 45+MPH the AC compressor comes on for 2 seconds, then 
shuts off 
> for 3-4 seconds then comes on for 2 seconds again, and over and 
over. 
> Doesn't that seems a little excessive? How can it be fixed? Can 
this be 
> adjusted?
> 
> Thank you
> 
> David
> 6286