A/C compressor replacement

KEKOKA93

MEMBER
2008 MAZDA CX-7
2.4L
V8
4WD
200,000 MILES

Recently the A/C in my car stopped working where it was only producing hot air even on the lowest setting. I then realized that this was either the result of the A/C needing to be recharged which I did and unfortunately to no effect or the A/C compressor was malfunctioning. I then went to replace my A/C compressor, then noticed that the A/C air intermittently changes from cold air to cool to lukewarm air. During the lukewarm air stage, the air tends to be particularly humid. So, my question is, why do you believe that when it gives cool to lukewarm air and why the air is humid? Is this a result of moisture being trapped in the A/C line? Or is this resulting from a different issue in the A/C unit?

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

This would not be anything trapped in the A/C line. Warm damp air is caused by the compressor not creating a pressure differential in the system cool the evaporator and remove the moisture.

So, we need to start with checking the pressure of the high and low side of the system.

At this point we could have it overcharged, or the system is still weak.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

This means we need to know what the pressures are when the A/C is on and then we can determine the next steps.

I am attaching the chart below which will help with determining what the issue could be based on the pressures.

Let me know what questions you have, and we can go from there.

Thanks

Image (Click to make bigger)