"Groaning" sound when a/c starts

[BrianG]

I recently started hearing a "groaning" sound when the a/c system is turned on. The sound is like a low pitched creaking door. At first I thought it might be a duct control door making noise as it opened or closed but I'm starting to wonder if it is the a/c compressor starting up. The sound only lasts for about a second and is intermittent so has been impossible to pinpoint. All a/c functions are working fine. I'll be heading to the dealer in a week or so for the 25,000 and am wondering if I should push them hard over this noise. Is anyone else hearing anything like this?

[Marlin]

<div class='quotetop'>QUOTE(BrianG @ Jul 23 2006, 12:18 PM) [snapback]290967[/snapback]</div>

I recently started hearing a "groaning" sound when the a/c system is turned on. The sound is like a low pitched creaking door. At first I thought it might be a duct control door making noise as it opened or closed but I'm starting to wonder if it is the a/c compressor starting up. The sound only lasts for about a second and is intermittent so has been impossible to pinpoint. All a/c functions are working fine. I'll be heading to the dealer in a week or so for the 25,000 and am wondering if I should push them hard over this noise. Is anyone else hearing anything like this?
[/b]

Mine started doing that for a while, but I think it's stopped. At least I don't notice it anymore if it does.

I've read other complaints about this noise. It doesn't seem to cause any problems. I always though it was something in the ducts as well.

[DaveG]

<div class='quotetop'>QUOTE(Marlin @ Jul 23 2006, 09:39 AM) [snapback]290979[/snapback]</div>

Mine started doing that for a while, but I think it's stopped. At least I don't notice it anymore if it does.

I've read other complaints about this noise. It doesn't seem to cause any problems. I always though it was something in the ducts as well.
[/b]

I've noticed that in mine occasionally too - I think it only happens when the AC system has to change the airflow from recirculate to direct and vice-versa. I suspect that it's the sound of the car moving the baffles inside to direct airflow. On my dad's old car, it was a pneumatic system. Not sure about Prius, if it's servos or something else.