Re: Heater Control Valve on 90 A90 Q20V

[steveb@falcon.kla.com (Steven Buchholz)]

> Posting for a friend who has a question about his 90A90.  He was replacing the 
> heater control valve and noticed that the nipple on it was broken off.  The 
> new valve has a nipple on it and he was wondering if on this model there is 
> not supposed to be a vacuum line to it (meaning that coolant is always 
> directed into the core).  He checked around and found a line in the dash that 
> appeared to be capped at the factory.  Anyone been there.....?  
> 
Your friend has probably been helped by the dealer, or someone else that 
worked on the car in the past.  If the car didn't need a heater valve, why
would Audi pay the $3 it cost for one?  If the 90 is like the 5k/100/200/V8
the heater valve is left open almost all of the time so if they broke the 
nipple off you wouldn't likely notice it.  When the desired air temp is set
to the minimum setting the valve is closed ... so that the A/C doesn't have 
to fight the heater core.  If it were me I'd probably fix it, but it really
can be foregone ...

HTH!
Steve Buchholz
s_buchho@kla.com
San Jose, CA (USA)