Charging a custom system.

[Legitness211]

Hello everyone, I started to charge the custom system with the "plateau" method, but It was a little bit complicated to me since I don't have a lot of experience.

So at the end I added 2 cans of 12oz each, so we can say that It has 24oz. I still see a little bit of bubbles on the sight glass, and I don't feel satisfied with the temperature.

This are the results:

Civic 1990
24oz aprox
33-35°C ambient 2.00pm
1500rpm more or less
Low 36 psi High 310 psi
Max blower, recirculation on, windows open

Center vent temp 17.5c

I feel the high side is too high and the vent temp, what do you think?

[tbirdtbird]

For the USA viewers,
17.5C vent temp is 63*F
35C ambient is 95*F

You will not and should not clear a sight glass with R134. If so, you have overcharged.
You may be overcharged now.
Did you follow along with the pressure readings as you slowly charged up?
Did you pull a good vacuum?
Do you have too much oil?
When you switched cans were you careful to not get any air in the system?
Is the condenser installed upside down?
are the condenser fans working?
Are any of the hoses very close to exhaust heat and such?

[Legitness211]

For the USA viewers,
17.5C vent temp is 63*F
35C ambient is 95*F

You will not and should not clear a sight glass with R134. If so, you have overcharged.
You may be overcharged now.
Did you follow along with the pressure readings as you slowly charged up?
Did you pull a good vacuum?
Do you have too much oil?
When you switched cans were you careful to not get any air in the system?
Is the condenser installed upside down?
are the condenser fans working?
Are any of the hoses very close to exhaust heat and such?

I putted about 5.5oz of PAG100, as you suggested here: https://autoacforum.com/viewtopic.php?t=14913.
I see a little bit of bubbles on the sight glass, so at this moment it is not clear, pulled a good vacuum?, I think yes, I did 20 minutes vacuum, then Iet the car in vacuum overnight, with the pump off, then today I did 1 hour of vacuum and then charged.

I tried to follow the pressure reading, but it is complicated since the high side goes let's say for example, 10psi up when I charge, then after a minute It goes 10Psi low, then again 5psi up, so I don't now, maybe I'm doing it wrong. But from 12oz to 24oz the temp vent never came down 17.5°C.

The condenser is installed in the correct way. https://autoacforum.com/viewtopic.php?t=14909

Both fans are working, I don't have a way to know if the airflow is enough, all I can say is that I have never had engine overheating problem even on the traffic on very very hot days.

The 2 lines from the compressor are near the exahaust manifold, I will post a picture.

When you switched cans were you careful to not get any air in the system?: yes, no problem with that, but before disconnecting the lines when trying to get the remaining r134 on the high side manifold hose, I let a little bit of air let's say about 1.5 seconds to the system, so I guess I screwed everything and I have to start over, but I don't think that's the problems because as I mentioned, that was before disconnecting the ac manifold, and after getting all the readings.

[Tim]

When mounted, is the # 8 fitting on the condenser on top or bottom?

[Legitness211]

When mounted, is the # 8 fitting on the condenser on top or bottom?

Yes sir, It is all connected correctly

[Tim]

The only free answer I am giving out today. As others have said, overcharged. If the PF condenser is plumbed correctly, you should be able to match the original R12 spec.


Refrigerant Type R-12
Capacity 1.98 lb (US)

[Legitness211]

The only free answer I am giving out today. As others have said, overcharged. If the PF condenser is plumbed correctly, you should be able to match the original R12 spec.


Refrigerant Type R-12
Capacity 1.98 lb (US)

Well I'm not sure if It would meet the original specs, because everything is custom, the hoses, the condenser, the compressor, the receiver, the evap, the txv.

[Tim]

The only free answer I am giving out today. As others have said, overcharged. If the PF condenser is plumbed correctly, you should be able to match the original R12 spec.


Refrigerant Type R-12
Capacity 1.98 lb (US)

Well I'm not sure if It would meet the original specs, because everything is custom, the hoses, the condenser, the compressor, the receiver, the evap, the txv.

Okay.

[tbirdtbird]

" I let a little bit of air let's say about 1.5 seconds to the system,"
Not good at all. Air in system will kill the performance

That comp is ridiculously close to the exhaust, and is killing your performance. Insulate that area.

"all I can say is that I have never had engine overheating problem even on the traffic on very very hot days."
That has no meaning when it comes to AC. The AC is way more sensitive to proper condenser heat exchange (good fans) that the engine cooling system.

The pressure reading you should be paying the most attention to is the low side, not the high side.

" But from 12oz to 24oz the temp vent never came down 17.5°C."
This shows there is something wrong. Are you certain that the larger condenser fitting is on the TOP of the condenser

[Legitness211]

" I let a little bit of air let's say about 1.5 seconds to the system,"
Not good at all. Air in system will kill the performance

That comp is ridiculously close to the exhaust, and is killing your performance. Insulate that area.

"all I can say is that I have never had engine overheating problem even on the traffic on very very hot days."
That has no meaning when it comes to AC. The AC is way more sensitive to proper condenser heat exchange (good fans) that the engine cooling system.

The pressure reading you should be paying the most attention to is the low side, not the high side.

" But from 12oz to 24oz the temp vent never came down 17.5°C."
This shows there is something wrong. Are you certain that the larger condenser fitting is on the TOP of the condenser

Talking about the condenser yes. I'm really sure the #8 at the top and the #6 at the bottom, the condenser is new.

About the exhaust manifold, do you have any recomendation about insulating the area?, which material to use, and should I insulate the manifold or the compressor? Do you think that could be the main problem?

And when you say the low pressure, that means that with the plateau method, you have to keep an eye at the pressure rise on the low side and not on the high side?. Of course making sure that the High does not go above 2.5x. Correct me if I'm wrong please, because I was paying attention just to the high side when charging.

And talking about the Air, yes, I Will evacuate and charge again.

And about the fans, I don't really know how to tell if the airflow is good enough, but for example I have a 2002 Corolla with an amazing AC, literally you just turn on the AC and in a couple of seconds It starts to blow freezing cold, but the fans on the radiator are really slow compared to the fans that I have on the Civic.