2018 Silverado 1500 A/C Recharge after condenser replacement

[Janderson28]

Hi,

I recently replaced my A/C condenser. It had a leak last August so I didn’t bother to replace it until now. I hooked up a set of manifold gauges and vacuumed out the system. It holds a vacuum just fine but the truck will not take Freon. Any ideas what the issue would be? 

[Snowcamo]

Are you using a refrigerant can with a screw tap hose?

[Janderson28]

No I’m not. Used manifold gauges and a vacuum pump. After I unhooked the vacuum I let it sit for 45 minutes. It held vacuum the entire time. After I tapped the A/C can I could see Freon go through the sight glass. It just wouldn’t flow into the low pressure line 

[Snowcamo]

I always fill the condenser first so it does not slug the compressor with liquid. Also allows you to fill the condenser with liquid and charge quicker. 

[CamGTP]

You basically have zero choice when it comes to filling the system with freon while using your own gauges. You only fill through the low side port, the freon is going to enter the system as a gas or liquid whether you like it or not.

 

Is your truck R134a or is it 1234yf?

 

I just did a car like 2 weeks ago with my gauge set using R134a. After I pulled vacuum and started to charge the system it had no problems sucking it down once I cracked the low side valve open.

[Janderson28]

What do you mean zero chance? I’ve done this before with 134a. Same process you’re doing. 
 

This is a 1234yf system. The problem I’m having is it won’t suck into the low side port. As soon as I crack the low side on the gauge it will fill into the eye glass on the manifold gauges but will not suck into the low side port.   

Edited May 28, 2023 by Janderson28

[CamGTP]

For the hell of it what happens if you crack open the high side to trickle a little in. Maybe it'll start pulling the freon in then.

[Snowcamo]

With the ac off, system in vacuum you are charging liquid via inverted can.  Charge it through the high side to spec and enjoy the ac.  

 

 

[No Tyme]

I would just be happy to find the low pressure line on my 18 Silvy 5.3. I seen videos of it being down low by the air box but I don't see it.

[tbarn]

I believe this will be your low side port. Not 100% sure though.

[rav3]

13 hours ago, No Tyme said:

I would just be happy to find the low pressure line on my 18 Silvy 5.3. I seen videos of it being down low by the air box but I don't see it.

 

[No Tyme]

LOL, they buried it to make it harder for the induvial and more costly to have it done... Thanks

[No Tyme]

FYI, you will need a newer hose as the older charge hose for 134A will not attach to the 1234YF... if you can't find the adapter

[No Tyme]

Darn I forgot I posted this. After all the issues I was able to just add a bit of Freon to my system and it made a world of difference. Too bad you need to be a contortionist to get the job done.