I have tried searching and can't find anyone describing my situation.

I've just had my Octavia in for a service and there is now a strange noise coming from under the dash area when I turn the heater fan on.

The noise can only described as someone blowing down a big metal pipe, quite low pitched and has a breath like quality to it. The pitch doesn't alter if I increase the fan speed.

It disappears if I turn the heater fan off and doesn't come back straight away when I turn the fan back on, taking approximately 20 seconds to become audible again, almost like it's building up pressure?

Any ideas?

Cheers, Dion.

If it's like a a drone sound, sounds like there mite me somthing traped in the fan take it out and make sure there's no crap in there like a leaf etc traped

was the pollen filter changed when it was serviced

was the pollen filter changed when it was serviced

I'll have a look in the morning when I've finished work.

i'd suspect something weird has happened if / when they changed the pollen filter. Either they haven't put the lid on properly or the foam under-pad is covering the inlet holes for recirc...

Checked the service sheet this morning and no mention of the pollen filter being changed.

 

This afternoon, I removed the pollen filter (some small leaf particles, not much else) and started the fan and there was no noise present. I refitted the pollen filter and everything is good again.

 

I have absolutely no idea what caused the noise. Thanks to all those that helped.

hi i have strange sound too its like turn indicator sound any ideas ?

Mine did this the other day too, like a very faint indicator tick.

 

I thought my keys were swinging against the steering column or that I'd left my indicator on!

 

It's done it twice now, only for 5-10 seconds though.

Leaves in the fan cage.  You need to remove the fan and clean all the crud off it & blow out the motor as well http://www.briskoda.net/forums/topic/239500-irritating-squeal-from-air-con/. 

 

It isn't a hard job - if you can change the oil or brake pads then you can pull the fan.

 

Obviously, clean all the rubbish from upstream as well - plenum area, etc

Leaves in the fan cage.  You need to remove the fan and clean all the crud off it & blow out the motor as well http://www.briskoda.net/forums/topic/239500-irritating-squeal-from-air-con/. 

 

It isn't a hard job - if you can change the oil or brake pads then you can pull the fan.

 

Obviously, clean all the rubbish from upstream as well - plenum area, etc

Thanks now need find time to do this.