W221 heater/climate control issues

[JamesS777]

Hi all, I have a 2008 S320cdi and ha e noticed that I have a few issues with the heating climate controls.

• Recirc button doesn’t work and doesn’t light up
• Fans don’t speed up when you turn them up or but it to front screen demise

Any ideas what this could be or where I should start?

Thanks

 

[Botus]

the fan on these is one constant speed thing under the glove box... the air flow changes based on the angle of dangle, I guess like variable vane turbos do it,

is it running at all ? (couldn't decipher from your post) its quite common they get a bath, I think from the sun roof drain and or leaf litter and the motor stops after water leaks give the motor brushes a hard life

 

[JamesS777]

Thanks and yes they are kind of working just don’t feel very powerful. It also takes longer to demist the passenger side of the windscreen.
It also takes quite awhile to warm up even though the engine temp is up to normal. Is it worth checking the valve control unit?

 

[Botus]

there's a strange valve under the bonnet near the wipers that fails, mine probably needs it about £50 (10) and (170) and if you have rear AC a more complex and silly money £400 thing (420) behind the right front wheel (that has the recirc pump for residual heat "REST" in the back). Front or all car recirc is I think up by the wipers. They fail on all car as its never used.

As for Air recirc - its auto if you have rear AC or manual on the others.

https://nemigaparts.com/cat_spares/epc/mercedes/1/fg/221171/63v/83/