AC Cooling Increase

[ProtonXX]

Was looking around today and notice Walmart was selling cans of 134A+ which was supposed to be 50% colder. Also there seem to be a craze with converting the factory 134A to HC-12A, which supposed to be much colder & alot easier on the engine/ac compressor(because of less pressure). Has anyone has any experience using these coolants?

[northvibe]

I have not..sounds sorta like a evil walmart ploy. What you can do to get your AC cooler is use pipe insulation on the AC lines in the engine bay! heres the link with pics!http://forums.genvibe.com/zerothread?id=4914

[djb383]

How does insulating the a/c hose work. In the picture, the hose with the insulation wrapped around it is the cold hose but that is the refrigerant hose that is LEAVING the passenger compartment, not ENTERING it. After the refrigerant leaves the passenger compartment it's under low pressure and enters cold into the compressor, is compressed, and leaves the compressor hot and under high pressure. The hot refrigerant line doesn't turn cold again until it passes the expansion valve/orifice tube, which is inside the passenger compartment, not under the hood. Again, the cold line under the hood is leaving the passenger compartment, not going to it.http://www.familycar.com/ac1.htm

[northvibe]

I do not know personally about the in/out lines of the car. But insulating that line made the AC much colder and if you read the whole thread there were some people doing tests with temp gauges and it shows at least a 5 degree cooler ac.

[djb383]

Ok, I still don't understand how it works since the cold line, the one being insulated, is the line exiting the passenger compartment and the hot line is entering the passenger compartment. But, I've never said I was the sharpest tool in the shed so I'll give it a try this weekend. Hope it does work 'cause I've already done the cable/trap door thingy.

[northvibe]

Im sure you'll notice a diff! let us know how it goes

[prathman]

Quote, originally posted by djb383 »Ok, I still don't understand how it works since the cold line, the one being insulated, is the line exiting the passenger compartment and the hot line is entering the passenger compartment.I'd still expect some benefit. If the low-pressure return line picks up heat from the engine compartment then the refrigerant will be hotter than otherwise and will therefore be hotter still after getting compressed. The hot, compressed refrigerant is then cooled, but if it starts out hotter I'd expect it to still retain some of that extra heat when it goes back into the passenger compartment through the high-pressure line. When it is then allowed to expand and cool it won't be as cold as possible due to that extra heat.I have no idea how significant the above effect is in practice so I'll be interested to hear of your before vs. after results.

[joholste]

I would expect that insulating that line helps due to the fact that the AC doesn't have to cool the air as far to get to the cold status, so it there for allows it to be cooler, and works with less load.

[djb383]

Regardless of how much you insulate the low pressure (cold) line, the high pressure line leaving the compressor is hotter than hell even after the refrigerant has been cooled by the condenser in front of the radiator. At the firewall, where the lines enter the passenger compartment, the high pressure line is still hot.Like I said, I don't understand how it works but I'm willing to try it.

[ProtonXX]

http://forums.tdiclub.com/showthread.php?t=145180I double Insulated my AC line, buts its 120 degrees these days, Im going to try hc-12c out.

[bergse01]

would you think adding some sort of metallic cooling fin to the hot line have any benefit?

[bergse01]

In case people have missed this in the "Problems and Warranty Issues" area...http://forums.genvibe.com/zerothread?id=1315going to give this a try before spending $$$ on metal fins...

[engineertwin2]

Welcome bergse01!You can extract some heat by adding cooling fins to the hot line, however this will prove to be difficult and reduce efficiency of the system.The process is irreversible to begin with, but the best way to improve A/C performance would be to resize the orifice plate and use a different refrigierant (one with a lower dew point) so that the temperature can be reduced even more before you reach the "condensate point."If you extract too much heat too soon, you can actually prevent the A/C from getting as cold as it currently does.As it is, I live in Phoenix, AZ and I won't bother with this one...basically, I am not sure if the condenser return line was designed for a specific heat input from the engine compartment or not. If it was designed for a specific heat input (as it should've been), then I would be concerned about the possibility of reaching brittle points, etc, on the metal tubing.

[bergse01]

Thanks for the welcome. I figured there would have been some sort of factory addition to the hot line if it was necessary to have extra heat removed from it. I've tried adding additional coolant, but, no real results. I'm going to try the temperature vent adjustment from my previous post. seems the best option. i guess i was just throwing out ideas.

[bergse01]

In case people have missed this in the "Problems and Warranty Issues" area...http://forums.genvibe.com/zerothread?id=1286 going to give this a try before spending $$$ on metal fins...

[kevera]

Hahaha,Thanks bergse01,I just learned how to remove my cross bars with ease.Nova always had a way of explaining things in the simplest way.

[bergse01]

well, if I understood the link I reposted, and the pictures with it, I don't think my air is going to get any colder. oh well, worth the shot. my car does get cold over time, just used to when i had my taurus that it made the inside a meat locker before you even had time to put on your sweater.