any A/C techs in here?

[bcp]

Yesterday I was running the truck with a/c, it was blowing cold. I shut the truck off for about 45 minutes, when I started it again I had no a/c.
Got home and checked, the compressor was not engaging.
Pulled all fuses and checked them. All good.
Went and purchased a can of freon that had the guage on it ( I know, no real accuracy here)
went outside of the parts store and turned on the a/c, connected the can to the shrader (sp) valve and read 55lbs on the low side.
I sqeezed the trigger thing on the can and heard the hiss like freon was being dispensed.
the compressor kicks in right away.
Cold air blowing again.

now here is the intersting part.
When I was walking back around to get in the truck I noticed a tab on the can that said to remove before using. I had not removed it before using.
This means that the hiss was not freon going it, but instead freon was coming out.
went back around and put it back on the fitting (low side) still reading around 55, half remembering some A/C stuff from 100 years or so ago, I let freon out until the pressure was down to 45 low side while running. Outdoor temp was 91 at the time. ( I remember that this makes a difference, I just dont remember the specifics on it)
A/C ran great, colder than ever, ran great again this morning, again, colder than its ever been.
Since I didnt check the high side I cant compare to see if something is going on. And I did not check to see what the static pressure was when the system was off.

I did have a tube replaced by the dealer about 3 months ago when it had a slow leak.
Do you think they overfilled it and that plus the outdoor temp was enough to cause an issue, or do you think I have debris in the system causing it to clog, or could I have a pressure sensor that is bad.

 

[Floyd2004]

Its because it was overfilled. 55psi is way too much in there! Should be around 35-38psi for around 90f. 55psi should have been good if it was about 110f outside lol

 

[DEEKAYPEE8569]

Yesterday I was running the truck with a/c, it was blowing cold. I shut the truck off for about 45 minutes, when I started it again I had no a/c.
Got home and checked, the compressor was not engaging.
Pulled all fuses and checked them. All good.
Went and purchased a can of freon that had the guage on it ( I know, no real accuracy here)
went outside of the parts store and turned on the a/c, connected the can to the shrader (sp) valve and read 55lbs on the low side.
I sqeezed the trigger thing on the can and heard the hiss like freon was being dispensed.
the compressor kicks in right away.
Cold air blowing again.

now here is the intersting part.
When I was walking back around to get in the truck I noticed a tab on the can that said to remove before using. I had not removed it before using.
This means that the hiss was not freon going it, but instead freon was coming out.
went back around and put it back on the fitting (low side) still reading around 55, half remembering some A/C stuff from 100 years or so ago, I let freon out until the pressure was down to 45 low side while running. Outdoor temp was 91 at the time. ( I remember that this makes a difference, I just dont remember the specifics on it)
A/C ran great, colder than ever, ran great again this morning, again, colder than its ever been.
Since I didnt check the high side I cant compare to see if something is going on. And I did not check to see what the static pressure was when the system was off.

I did have a tube replaced by the dealer about 3 months ago when it had a slow leak.
Do you think they overfilled it and that plus the outdoor temp was enough to cause an issue, or do you think I have debris in the system causing it to clog, or could I have a pressure sensor that is bad.

Overfilling the system can cause it to work improperly. The best thing to do is find the part of a maintenance manual like a Chilton's manual to find what the proper pressures should be. OR you can get a pressure gague specifically for auto A/C systems and hook it up to the system in the car. The gague has two dials; one for high side and one for low side; with indicators for proper pressures, etc..

Something else to note; charging an automobile A/C system should be done with the car running at idle, with the A/C system on MAX settings; as cold as it can get, with the fan on HI; but you already knew THAT.

 

[bcp]

Im running over to sears tonight and picking up a manifold gauge and a vacuum pump for A/C
I did find some of my ancient A/C manuals, (they still used dry Ice right?) but since they are all for r-13 it really is not the same.
So, I found some numbers on the internet (so I know they are correct) and I should have around 40 to 45 on the low.
also had the readings for low vs high in various temperatures and what the static pressure should be reading once it equalized when turned off.
I have enough numbers now for my specific system to determine if the only problem was the over fill.