In cabin noise when A/C turns on

2015 VOLKSWAGEN JETTA
72,000 MILES • 1.8L • 4 CYL • 2WD • AUTOMATIC
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KMB687
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When the blower motor is on level 1, 2 or 3 you can hear a hissing, gurgling behind the center vents, only when the A/C is on. It is not the blower motor making the noises. When the A/C is on, the air blows cold as it should. All items of the system seem to function appropriately, however, there is that noise.
Jun 4, 2021 at 3:06 AM
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JACOBANDNICKOLAS
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Hi,

There is a chance the condenser drain isn't allowing enough condensation to drain. Basically, there is a drain that can get plugged. Chances are, you have seen water draining from vehicles when the A/C is running. If that is restricted or blocked, it could cause what you hear.

If you look at the attachments below, they explain how to remove and replace the condenser water drain. Try this and see if there is a lot of water that comes out when removed.

Let me know what you find..

Take care,

Joe

See pics below.
Jun 4, 2021 at 2:36 PM
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KMB687
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Joe, thank you for the reply and the diagrams they were helpful. I took everything apart and nothing was blocked. Any other ideas?
Jun 6, 2021 at 9:09 AM
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JACOBANDNICKOLAS
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Hi,

Does it happen with the A/C off and the heater on? Is it loud enough for you to record and upload for me to hear?

If it is only when the A/C is on, a gurgling sound can simply be from the refrigerant in the system. Oftentimes, it is caused by being over or under-charged.

Let me know.

Joe
Jun 6, 2021 at 12:20 PM
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KMB687
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Only happens when A/C is on.

I will upload an sound file tomorrow.
Jun 6, 2021 at 3:05 PM
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JACOBANDNICKOLAS
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Sounds good. Keep in mind, often times a gurgling can be the Freon in the system and is considered normal. Once I hear it, I should be able to tell.

Take care,

Joe
Jun 7, 2021 at 2:01 PM
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KMB687
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I have uploaded it twice now, has it not come across?
Jun 7, 2021 at 2:06 PM
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STRAILER
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it sounds like could be overcharged or it has too much oil in the system. has the system been apart? Also is this system a134 or R-1234yf?
Jun 8, 2021 at 3:00 AM
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KMB687
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Too much oil in the system?
I am assuming it has been apart at the dealer when they got this vehicle in - its a used car purchase. Google says this is a R134a refrigerant type.
Jun 8, 2021 at 3:32 AM
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KMB687
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I have not noticed until today, there is also a groan that happens when the A/C is turned on as well.
Jun 8, 2021 at 7:15 AM
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JACOBANDNICKOLAS
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Hi,

What you do is have the system vacuumed down and recharged. Here is a link that shows how it's done and discusses the oil in the system:

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

Let us know if this helps.

Take care,

Joe
Jun 8, 2021 at 1:45 PM
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KMB687
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Thank you, I appreciate your help. I have set up time with a good local shop to get this all dealt with!
Jun 9, 2021 at 12:48 AM
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JACOBANDNICKOLAS
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Hi,

You are very welcome. If possible, have them listen to it in person to confirm what we recommended. Although the recording is very helpful, not being there makes it a little more difficult.

Take care and if you have the chance, let me know the outcome. I'm interested in knowing and confident that others will benefit from your response.

Joe
Jun 9, 2021 at 1:05 PM
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KMB687
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Outcome, you were correct Joe. The system needed to be vacuumed down and recharged, no issues now, no sounds and blow much cooler.
Jun 15, 2021 at 3:36 AM
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JACOBANDNICKOLAS
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Hi,

I'm glad to hear it's taken care of. And if it's colder, all the better. LOL

Take care of yourself and please feel free to come back anytime in the future if you have questions. You're always welcome here.

Joe
Jun 15, 2021 at 2:24 PM
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