I feel like I’m going in circles with my 97 k1500. I have now replaced the entire AC system and I’m running into the same issues. The compressor isn’t turning on when charging it and when I jump it to fry and get more refrigerant in it, the high side climbs immediately to 400,500… I had a mobile mechanic come over and flush the entire system and replace the condenser and it is still happening. I feel like we must be missing something obvious, how can everything be brand new, flushed clean and still run high. My only thought is that we replaced the compressor first and then everything else - could there be enough crap in the compressor from the old lines to cause blockage? Has anyone had this issues before? Any advice? I’m in Texas and I need the AC to work or the car might need to go which would suck because I just finished so much work to it.

 

Did you replace the compressor line assembly as well? The flared sections of tubing on those lines are mufflers to reduce noise, and the recommendation is to replace them instead of try to flush them because they contain several small passages that will catch debris and cause blockages.

Did you just replace the compressor or did you get a compressor kit that included an accumulator, orifice tube, and system flush?

 

At this point, everything has been replace, lines, compressor, condensor (most recent addition). The condensor came with an Orifice tube. We even flushed the new lines and whole system when installing the new condensor.

I vacuumed the system and it was holding pressure, I added not even a full can of Freon and the high side was way too high and the compressor didn’t kick on.

below you’ll see it holding vacuum and the readings after the one can of Freon.



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Not that this would be a cause, but the pic of the post-vac readings shows the low side is not in a complete vacuum. The needle should be up against the stop like it is on the high side.

How many ounces or grams was the can you added and what was the ambient temperature?

 

It was about 100 out. The vacuum seemed fine. It was holding. The can was 12 oz.

 

At 100* those pressures are normal for the charge level (approx 38% system capacity for standard cab - if it’s a crew cab it would be about 33%).

Static pressure should reflect the ambient temp within about 10 PSI. The curve changes above 80* but my experience with AC has taught me it’s still reasonably close up to 100* if the system charge is not excessively low or high.

If I’m not mistaken, both the high and low side service ports are on the compressor line assembly, so for the pressure to reach 300+ PSI immediately indicates a few things.

These are just possibilities.

1) The lines are switched at the condenser. Make sure the compressor line is connected to the top fitting and the line to the evaporator is connected to the bottom fitting.

2) There’s a total blockage in the line assembly or the condenser. Keep in mind that “new” does not mean “good.” Every parts manufacturer, OEM or aftermarket, makes mistakes and sometimes those mistakes make it out the door anyway. Google the brand names of the parts in combination with “recalls” and verify the dates for them are current if you find any.

On the note of total blockages, is it possible a plug or cap for one of the components wasn’t removed before assembly? Or did you stuff paper towels into any open lines or ports that you may’ve forgotten?

3) Engine off, turn the compressor clutch by hand. It should mostly turn freely with minor resistance - similar to turning over an engine by the crankshaft bolt when the spark plugs are still in the heads.

Also, I forgot to ask - what is the gauge reading on the low side when the high side is building?

 

[QUOTE=atx522;479529]I feel like I’m going in circles with my 97 k1500. I have now replaced the entire AC system and I’m running into the same issues. The compressor isn’t turning on when charging it and when I jump it to fry and get more refrigerant in it, the high side climbs immediately to 400,500… I had a mobile mechanic come over and flush the entire system and replace the condenser and it is still happening. I feel like we must be missing something obvious, how can everything be brand new, flushed clean and still run high. My only thought is that we replaced the compressor first and then everything else - could there be enough crap in the compressor from the old lines to cause blockage? Has anyone had this issues before? Any advice? I’m in Texas and I need the AC to work or the car might need to go which would suck because I just finished so much work to it.[/QUOTE
You problem is on the ac condenser the lines are crossed