ZacHolley

I bought an 03 ram 2500 yesterday and at night time and stuff the air out the vents is so cold it will run you out of it.

during the day when its setting still it blows warm air and the compresser kicks on and off every like 5 or 10 seconds.

I added freon and checked the pressure on the low side and the freeon is at the right setting.

what else could cause the compressor to kick on and off at such a high rate??

thanks in advance
Zac

Spooler

What is the High side doing???? Both pressures have to be correct. You could have a blockage, overcharge, air in the system, to much oil, or just the normal A/C crap we are going thru with it blowing hot out the passenger vents.

coyote204

The best way to check your system is to recover the refrigerant charge, pull a long and deep vacuum, and weigh new refrigerant in to factory specs. The low side pressure could be right after you added refrigerant, but the high side could be through the roof causing the compressor to cycle erraticaly because of high heat and pressure.

pwregan

thats what my 1999 ctd is doing, i probanly overcharged it and now compressor wont stay on, how can i bleed some of the pressure off?

ZacHolley

most of that is jibberish, how do i pull a long deep vacume and all that?? still new to this stuff.

handymantim

My first guess is the system is overcharged. During the day when it is hot, the pressure in the system will go up and I'm assuming it is hitting the high pressure switch limit.

The best solution to this problem would be to buy a gauge set and find out what the pressures are for the high and low side during the day when you are having the problem. I don't know what the high side pressure limit is on your truck but for some other vehicles it's between 350 and 400 psi.

Bleeding off 134 is easy and supposedly not bad for the environment. Assuming you don't have a gauge set, find one of the schrader valves and use a small screw driver to let some out. Do a little at a time until the system operates normally.

ZacHolley

well it still does'nt cool very much at all during the night i mean it does cool alot more especially when in motion but for sure not like it should!!

ill go buy a pressure guage kit wednesday and we shall see

MikeyB

To do it right buy a set of good gauges. Do Not go by the idiot gauge on the R134a cans that you buy at Walmart.
Go to my picture gallery and you will find the specs for the A/C system and the troubleshooting guide.

MikeyB

v8440

My advice is to take it to someone who knows what they're doing with a/c stuff. Messing around and guessing is a great way to end up with a pretty expensive bill, though within reason the high and low pressure limit switches should protect you from yourself-you just won't end up with working a/c if you run it against those a lot.