Help - AC droning after cabin air filter change

[Norcal470]

My mechanic changed the cabin air filter on my 2017 (something he has done before) and now I hear a droning noise when the AC fan is on high. Turning the fan down reduces the noise, and the noise goes away entirely if the fan is off. Thoughts on the cause? TIA

 

[KLF]

Maybe there was something on top of the filter, and when he pulled the filter out, it fell into the impellor of the fan. Maybe pull the filter out, use a mirror to look down into the fan.

 

[bloc]

Maybe there was something on top of the filter, and when he pulled the filter out, it fell into the impellor of the fan. Maybe pull the filter out, use a mirror to look down into the fan.

Sounds likely to me.

 

[04UZJ100]

Did he damage the recirculation dampener?

 

[Sandroad]

Be sure you put the HVAC in RECIRC before removing the filter to check the fan.

 

[pvchaitanya]

It could be something hanging or hitting the little impeller fan right below the filter. Like someone suggested, something may have fallen into the fan or hanging from the filter into the fan area and hitting it.

 

[Norcal470]

You all were right. Something fell into the AC unit when he changed the filter. Took the car back, he pulled out whatever was there, and the noise is gone. Thanks all.