Noisy Fan

On a hot day like today (98 degrees), if I come home and plug the car in to chart (car is sitting outside), shortly I hear fans kick on, I assume, to cool the battery pack. There is a fairly quiet fan noise coming from up front and a fairly noisy fan noise coming from the rear. Sounds like an unbalanced fan. A vibrating type of noise. This is a 2013 i3/REX. Anybody know if the rear fan is an easily accessible item or is it actually buried in the battery pack somewhere?

I only get the noisy rear fan when I have been running the range extender. Otherwise, just the AC. I think the rear fan is thermostatically controlled to cool the range extender.

Haven't been running the REX.

Fisher99 said:

On a hot day like today (98 degrees), if I come home and plug the car in to chart (car is sitting outside), shortly I hear fans kick on, I assume, to cool the battery pack. There is a fairly quiet fan noise coming from up front and a fairly noisy fan noise coming from the rear. Sounds like an unbalanced fan. A vibrating type of noise. This is a 2013 i3/REX. Anybody know if the rear fan is an easily accessible item or is it actually buried in the battery pack somewhere?

Click to expand...

The fan in the front pulls air though the A/C condenser (heat exchanger). The sound in the rear is the A/C compressor that is in front of the drive motor. The compressor can be loud when working hard or when failing

So I was thinking "hey, this is great! I now know that it's not a noisy fan. Just a compressor". Then you mention the "f" word... I recall seeing another thread about the cost of repair after a failed compressor contaminated the battery pack cooling system. Yikes!

But now that you mention compressor, this does really sound like a compressor rather than a fan, so maybe the noise I'm hearing is normal and not an indication of failure. Wish there was another i3/REX in my area that I could compare with.

Fisher99 said:

But now that you mention compressor, this does really sound like a compressor rather than a fan, so maybe the noise I'm hearing is normal and not an indication of failure. Wish there was another i3/REX in my area that I could compare with.

Click to expand...

The compressor can be surprisingly loud, even when working correctly.

You could also listen to the compressor on an i3 BEV which has the same compressor as a REx. However, comparing the compressor sounds of 2 i3's could be difficult because the compressor is a variable speed device whose speed depends on climate control settings, battery pack temperature, cabin temperature, etc.

Great info, as always. Thanks Art.