HVAC whistles Help!

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Sep 12, 2008 | 05:27 PM

lotusing

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From: s.jersey

HVAC whistles Help!

I have a 99 V70 that when the a/c is on the blower whistles.When turn the a/c off and keep the blower on, it stops.I replaced the cabin filter and it still does it.What is wrong?
Thanks

Sep 12, 2008 | 08:03 PM

tech

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From: Orlando, Florida

RE: HVAC whistles Help!

Does it also do it after you have the car turned off?

Sep 12, 2008 | 09:27 PM

lotusing

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From: s.jersey

RE: HVAC whistles Help!

Thanks for the response. No.If the fan is off or on it will not whistle. It only makes the noise when the a/c button is pushed and the blower on.

Sep 12, 2008 | 09:39 PM

tech

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RE: HVAC whistles Help!

Does the noise sound like it is coming from inside or outside?
The Orfice tubes tear and whistle when the compressor comes on or goes off.

Sep 13, 2008 | 01:31 PM

lotusing

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From: s.jersey

RE: HVAC whistles Help!

Definitely inside the car.

Sep 13, 2008 | 02:24 PM

tech

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RE: HVAC whistles Help!

Also see if you can hear it outside with the hood up. If it is the orfice tube you will be able to hear it under the hood about 1 foot from the firewall Passenger side.

Sep 14, 2008 | 12:04 PM

mr maraki

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RE: HVAC whistles Help!

Hey tech can you tell us more about the orifice tube? Mine whistles like a steam train turning on and off! It doesn't seem to be leaking though?

Sep 15, 2008 | 04:25 PM

tech

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From: Orlando, Florida

RE: HVAC whistles Help!

When they do this it makes it whistle. See pic. The 2 on the left are bad the right one is new.
Name: mine005.jpg
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Sep 15, 2008 | 10:07 PM

lotusing

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From: s.jersey

RE: HVAC whistles Help!

Sorry, I could notgetto the computer. You are saying to listen on the outside to find the source which may be the orifice tube? If it is it, I would lose all the freon in the system to change correct?
Thanks again