I have just changed from an EU5 SEAT Leon FR170 with a standard fit front mounted intercooler, to my new EU6 Octavia Scout 184 DSG.

Whilst having a nose around under the bonnet I noticed this car has an air to water intercooler fitted into the inlet manifold.  which radiator is used for the cooling of the intercooler, the engine rad or the air con rad?

Surprisingly the water pipework is quite warm when the engine is running so the cooling effect would not appear to be as good as an air to air intercooler?

 

I await technical comments from you guys re this matter.

Check this out, http://www.fichier-pdf.fr/2014/05/17/ssp-840233-ea288-diesel-engine-family/

Not sure its your exact engine, but there's lots of technical info.

To quote the cooling section - "Charge Air Cooling Coolant Circuit (Low-Temperature Circuit)

The charge air cooling system adjusts the intake manifold air temperature using a liquid coolant radiator. The charge air temperature is regulated by the ECM, which activates the V188 Charge Air Cooling Pump to regulate the charge air

temperature. The intake manifold temperature after the charge air cooler provides the reference value for actuating V188.

The coolant circuit for charge air cooling is connected to the engine coolant circuit by a non-return valve and a restrictor for filling and bleeding. During operation, there is no connection to the engine coolant circuit.

Actuation conditions of the V188:

• If the charge air temperature is below the target value, the pump is turned off or remains off

• If the intake manifold temperature is equal to or somewhat higher than the target value, the pump is activated in a

cycle. The on and off times (cycle times) depend on the charge air temperature and the ambient air temperature

• If the charge air temperature is significantly above the target temperature, the charge air cooling pump is run

continuously at full power"

Edited 31 October, 201510 yr by classic

Thanks Classic

That explains it and answers many of my queries. I now realise how complicated this engine is!!!

I have just changed from an EU5 SEAT Leon FR170 with a standard fit front mounted intercooler, to my new EU6 Octavia Scout 184 DSG.

Whilst having a nose around under the bonnet I noticed this car has an air to water intercooler fitted into the inlet manifold.  which radiator is used for the cooling of the intercooler, the engine rad or the air con rad?

Surprisingly the water pipework is quite warm when the engine is running so the cooling effect would not appear to be as good as an air to air intercooler?

 

I await technical comments from you guys re this matter.

It would be technically impossible to use the air con "radiator" (the condensor) as it is full of AC gas.  It's an interesting concept though - it might work if you integrated an evaporator into the IC and ran the AC all the time.

 

They probably use water/air as it's more compact.  Generally it's more efficient as there is a constant flow of water (which has a higher specific heat value than air) and it doesn't heat soak as much.

 

Rather than me write lots & pretend I have a clue, read these articles.  The author is quite good at explaining technical concepts in simple terms.

 

http://www.autospeed.com/cms/article.html?&A=107759

 

http://www.autospeed.com/cms/article.html?&title=The-Complete-Guide-to-Intercooling-Part-2-&A=107760

Absolutely endorse the autospeed.com site as it is full of terrific stuff as well as what Brad has highlighted.

Intercoolers are useful things to have on a turbo engine but probably don't get much action on normal uk public roads. I'll prepare to be corrected on that view though

I was reading through the training manual for the ea288 engine and the charge air system uses a coolant system with a separate radiator mounted (stacked) ender the engine radiator

It's not just the diesels either, my EU6 Leon 1.4 TSI ACT also has a charge cooler.

It's not a new idea either. Can anyone find an older example???

 

Late '80s GT4 Celica had them as did the first of the turbo Subaru Legacy / Liberty.

 

That Lotus is mid-90s isn't it?

 

Earliest was probably the 50s on diesels although it wouldn't surprise me if they had military applications in WW2.

'89 Esprit SE had it IIRC.