Air Con concerns

[AlfaACT]

Next is the (lower) half of the fan cowling ...

A point to note here, is that as the interior of the A/C box is assembled it effectively creates a wall between the switch area and the heat exchanger.

[AlfaACT]

Finally, is this a possible arrangement for the problematic capillary tube ... ?

[sportiva]

If you were to place the capilary just over the edge it would be in the direct flow the of air through the core. The question is did Alfa originaly place this capilary/temp sensor in the air flow or out of the flow? The above photo is 2D, I know, that from the tip of the temp sensor to the yellow wire is 70 to 80 mm lower you just don't sense that in the flat screen image.

[AlfaACT]

Here is a pic from in front, showing the (final?) location of the capillary.
The capillary has been relocated a little.
The only concern now is that the unsupported tube is likely to fracture at the switch - and rattle in the meantime. But there doesn't appear to be anything to secure it too.

[bonno]

For the thermostatic switch to operate effectively, it requires that the probe/sensor to be in the path of air flow being pushed out to the vents and probe centrally secured/cable tied to evaporator. When A/C system is running the temperature at the air vents should be around 6 degrees C.

[bonno]

Further to my previous post, here is a link to the experts advice on location of the thermostat probe/sensor location (DIY Thermostat Sensor repairs).
http://www.airsupplyinclv.com/services/air-conditioning-troubleshooting-guide/air-conditioner-temperature-thermostat-sensor-problems/

[GTVeloce]

Hi mate

You have two options with that capillary. Either squish it into the evaporator core or better still, attach it to evaporator return pipe. My 75 has it this way from the factory and I think it is probably the better location as the temperature can vary across different parts of the evaporator but the temp of the return line is probably a better indicator and it means you can get a solid connection. Then wrap it with some of that horrible, black, super sticky tape (I have a giant roll of it if you wold like me to send you some - I'm sure I owe you a lot more that that!).

[AlfaACT]

Hi GTVeloce,

Thanks!
Re the "horrible, black, super sticky" stuff: I have been wondering if there might not be a 20th C (if not 21st C) solution to this problem! If not, I might need to take up your kind offer. I'll be Dynamatting the floor & firewall - Yep! I have read your post on insulating the cabin - so I wonder if Dynamat might work wrapped around the exposed metal A/C pipes too?

[GTVeloce]

Interesting idea to use dynamat for that purpose. The only issue I see is that in some parts you will want probably more than one layer and often you need to bend it around a tight section - dynamat might be difficult to mould to such tight curves? The 'horrible, black, sticky stuff' does well at getting into crevasses. Otherwise it may well work. If you have ever tried to remove dynamat from a surface it is just as bad as the 'horrible, black, sticky stuff'...

I wonder what new cars are using for this purpose? Although they usually seem to have the pipes exiting directly out to the engine bay so condensation is not an issue and they use quite a different design for TX valve etc so maybe they don't need any?