Regular thump noise when HVAC on?

[altman]

So, I get a significant thump noise (and slight car shake) about every 30 seconds when my HVAC is on. The HVAC works fine. It might be happening when the car is moving but it's not noticeable then. HVAC set to 21C so warmer than outside, but not significantly so.

When I first noticed it (when sitting at a red light) I assumed I must have not been pressing the brake hard enough and hence the creep mode was somehow pulling a bit, but after doing some experiments it definitely seems to just be HVAC related. I can sit in the car, with "car off" on the dash, and every 33 seconds I hear/feel the thump. Turn off the HVAC and no thump. Pretty sure it's only been happening for the last month or so.

Anyone else have this?

 

[orlando]

Yes i do experience this also.

 

[Shorty]

I have the same experience. Has been going on longer than a month though.

 

[Russell B]

It's the compressor going on and off. Annoying until you know what it is, at least for me.

 

[altman]

It's the compressor going on and off. Annoying until you know what it is, at least for me.

Frankly, that's a bit sucky... surely it must be possible to have a soft-start on this? I've never noticed this on the prius, which has an electric AC compressor (vs belt-driven).

This is what happens when cars get too quiet - you start hearing the other systems!

 

[jerry33]

Frankly, that's a bit sucky... surely it must be possible to have a soft-start on this? I've never noticed this on the prius, which has an electric AC compressor (vs belt-driven).

The Prius has a variable speed scroll compressor so you never really hear it. I would have thought Tesla would do the same, but perhaps not.

 

[Austral]

Thanks gentlemen. I've been noticing this as well. Scheduled a service call next week for nothing perhaps. Good news overall of course. The HVAC has been excellent though in general.

 

[Atebit]

I have it too. I had a loaner last week with about 37K miles that also had it...

 

[fasteddie7]

Same here. It startles me sometimes when I'm sitting idle for a few minutes waiting to pick up the little man from school, but other than the noise and slight bump, it hasn't given me any issues.

 

[NWeHunt]

Also noticed this when sitting idle. Definitely seemed like the compressor to me.

 

[mastermason11]

Been happening to me for a long time now. I brought it in to the SC a few months ago (with other things I want to get fixed) and they said this was normal.

 

[outie]

Happens to the Model X as well. I have been hearing it and figured it's the AC.

 

[iffatall]

I started noticing this on my car about a year ago... around the time 7.1 got installed I think. Or whatever the update was that fixed the AC. And once I noticed it, it became more and more annoying. My mind always goes to it when I am in the car while stopped. Also, I have measured the frequency to be more like every 5-10 seconds.

Eventually I brought my car to the service center, and they said it was normal. I am not fully satisfied with the answer though, because I am pretty sure I did not have the thumping sound before, and even if I did, there is no way it should be called normal.