Car ac not cooling when weather is hot.

[Cusser]

What kind of condenser fan(s) were installed. Sounds like an air flow issue, that the condenser might not be shedding enough heat.

[JohnHere]

I agree that a condenser airflow problem might be causing the weak cooling. But since this is an aftermarket system of unknown capacity, it could also be an insufficient refrigerant charge.

I wonder, too, whether the new fan is rotating in the right direction--that is, is it moving air back through the condenser and radiator (correct) or is it moving air toward the front of the car (incorrect)?

Lastly, did the shop install any type of fan shroud along with the new fan? If so, and there's also a factory-installed shroud on the engine-side of the radiator, you actually might have an airflow restriction now.

[Tim]

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[Tim]

What refrigerant are you using? And did you use a parallel flow condenser?

[Tim]

Look like it is. How much refrigerant are you adding and what are your pressure readings?

[dasinc]

It's hard to diagnose a A/C system without knowing the Low and High side pressures. See if you can get those. Also you stated that the condenser feels colder to the touch. The condenser should never feel cold, it is usually pretty warm or hot. If it's cold it could suggest a restriction. Again, the pressures could be a help there. Is the small line that comes from the condenser to the firewall hot or cold?

[JohnHere]

Let me see whether I understand correctly. Do you now have a center-vent temperature of 22C (72F)? If so, 22C air from the center vent is certainly not adequate and borders on no cooling at all. You should be seeing center-vent temps of around 4C to 7C (40F to 45F) to get the cabin temp down to a comfortable level. Measure the conditioned air coming from the center vent using an accurate thermometer at an engine speed of about 2,000 RPM. If the measurement is not within the range of 4C to 7C, something is still wrong with the system and the shop has more work to do. Incidentally, five minutes is not nearly long enough for a thorough evacuation.

[Cusser]

I did a test the the problems I found were that the inlet and outlet temperature in the condenser were nearly the same, the difference was about like 5°C, but I'm gonna do another test with the all the conditions and gonna take note of all the temperatures to post them here.

5°C difference seems quite low to me. The condenser needs to cool hot refrigerant gas phase to liquid refrigerant.

1. Were the condenser fittings installed properly?

2. Is the electric fan (or fans) directing the air flow through the condenser rearwards towards the engine?

[Tim]

TXV Capillary tube attached correctly?

[Tim]

Condenser: Discharge line always on top!!!!!!!!!