Heat in Passenger Compartment
#1
Instructor
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I know that this topic has been discussed before. I've researched the site, read Roly Baldwin's article, read Adrians book on the topic and I'm still stumped. So I need HELP!!!!
It was 92 in Phoenix yesterday and our first 100 degree day is just around the corner. (It's hotter than the inside of the tents at LeMans on a hot June afternoon.)
Basic problem, with the AC off, fan speed at '0', wind screen and footwell vents to the left, temperature control at the coolest, and the engine just started.
Result, air coming from the drivers (LHD) vent and from the left side of the center dash vents. As the engine heats the air get warmer and warmer until it is down right hot. (This only happens on the drivers side not the passenger side. )
Action, using Roly's article and Adrians book I've determined that servo's 2 and 4 (Roly's numbers - Mixing chamber servo valves) are operating properly.
Why would this only effect the drivers side and not the passenger side?
Any ideas of where to look? Is there possibly some diverter valve stuck open?
(Note: Roly's article is excellent)
It was 92 in Phoenix yesterday and our first 100 degree day is just around the corner. (It's hotter than the inside of the tents at LeMans on a hot June afternoon.)
Basic problem, with the AC off, fan speed at '0', wind screen and footwell vents to the left, temperature control at the coolest, and the engine just started.
Result, air coming from the drivers (LHD) vent and from the left side of the center dash vents. As the engine heats the air get warmer and warmer until it is down right hot. (This only happens on the drivers side not the passenger side. )
Action, using Roly's article and Adrians book I've determined that servo's 2 and 4 (Roly's numbers - Mixing chamber servo valves) are operating properly.
Why would this only effect the drivers side and not the passenger side?
Any ideas of where to look? Is there possibly some diverter valve stuck open?
(Note: Roly's article is excellent)
#2
Advanced
Join Date: Feb 2002
Location: Houston, Texas
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Same thing happened to me last year, but only on the drivers side. Turned out to be a duct under the dash that was only partially connected. Any air leak allows (full) hot air flow from the heat exchangers at the rear. Only if zero air flow is allowed to the front does the system dump the hot air (always flowing through the exhangers) out at the rear, through the funny narrow vents near the rear shocks.
Bob K
1989 C4
Bob K
1989 C4
#3
Addict
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Dear JRB,
I bet the left mixing chamber valve is kaput. What I recommend is that pop of the actuating arm and manually position it until you remove the heat.
It is possible to have these things connected around the wrong way and they appear to work but the mixing chamber valve itself is in the wrong position.
Ciao,
Adrian
964C4
I bet the left mixing chamber valve is kaput. What I recommend is that pop of the actuating arm and manually position it until you remove the heat.
It is possible to have these things connected around the wrong way and they appear to work but the mixing chamber valve itself is in the wrong position.
Ciao,
Adrian
964C4
#5
Addict
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
A blogger is somebody who uses Blogs. A Blog is like a one page web site which is like an online daily journal. You can find the hosting sites on the internet. They can be public or private. Your own personal online newspaper column or editorial. If you visit my web site you can find a link on the bottom of my home page to blog I have set up as an advice column against getting scammed. You can have a blog for your 964 to list over time all the good and bad things that happened during your ownership.
They are a lot of fun actually.
Ciao,
Adrian
964C4
They are a lot of fun actually.
Ciao,
Adrian
964C4