| [GMCnet] Refrigerant: 134 vs Duracool [message #93223] |
Sun, 25 July 2010 20:35  |
k2gkk
Messages: 4452
Registered: November 2009
Karma: -8
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Senior Member |
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Was I imagining it or was somebody stating
that Duracool molecules are quite a bit
larger than those of 134a, thereby quite
a lot less prone to leaks?
My Tundra 8 cu ft 12/120 Volt fridge appears
that it is leaking refrigerant in the area
of the connection between compressor and lines
to the evaporator in the freezer compartment.
There appears to be oil residue down near the
compressor.
I'm wondering if Duracool might "plug" the leak?
Would using Duracool in the interior of a coach
really be safe? This is the fridge I removed
from my boat and if I can get the leak stopped
I'll use it as a beer/pop fridge in the garage
or put it into "Money Pit" if the fridge there
turns out to be non-functional.
Thanks!
~ ~ ~ ~ ~ ~ ~ ~ ~
~ Mac Macdonald ~
~ Oklahoma City ~
~~ "Money Pit" ~~
~ '76 ex - P.B. ~
~ ~ ~ ~ ~ ~ ~ ~ ~
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| Re: [GMCnet] Refrigerant: 134 vs Duracool [message #93227 is a reply to message #93223] |
Sun, 25 July 2010 21:18  |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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Senior Member |
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| k2gkk wrote on Sun, 25 July 2010 21:35 |
Was I imagining it or was somebody stating that Duracool molecules are quite a bit larger than those of 134a, thereby quite a lot less prone to leaks?
My Tundra 8 cu ft 12/120 Volt fridge appears that it is leaking refrigerant in the area of the connection between compressor and lines to the evaporator in the freezer compartment. There appears to be oil residue down near the compressor.
I'm wondering if Duracool might "plug" the leak?
Would using Duracool in the interior of a coach really be safe? This is the fridge I removed from my boat and if I can get the leak stopped I'll use it as a beer/pop fridge in the garage or put it into "Money Pit" if the fridge there turns out to be non-functional.
Thanks!
~ ~ ~ ~ ~ ~ ~ ~ ~
~ Mac Macdonald ~
~ Oklahoma City ~
~~ "Money Pit" ~~
~ '76 ex - P.B. ~
~ ~ ~ ~ ~ ~ ~ ~ ~
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Mac,
"Would using Duracool in the interior of a coach really be safe?"
Yes, we are talking about a flammable gas. About the same quantity as a stove lighter. And most of it is no different than the LPG you have a big tank of already (but that stuff is not very pure).
As a guy that once designed refrigeration systems for laboratories, I have been trying to find out more about HC-12, but the information is not readily available.
HC-12 is a 21% isobutane(c4h10) and 79% propane (c3h8). Both might be larger molecules than R-134(c2h2f4), but I would not count on that to stop a leak. Epoxy might. I used to buy a special epoxy for sealing up holes made by people defrosting with a hard tool. I haven't purchased any in years, but it can't be that different and still be epoxy.
I would clean the area where you found oil real well and then put a layer of a good epoxy putty over it.
I don't know where the leak is in my reefer, but I have a pretty good idea. I'm going to used a light hydrocarbon as a cleaner and then coat the suspect area with a penetrating (very low viscosity during set) epoxy and then pull a hard vacuum on the system. This all has to wait as I am going to do when the Duracool shows up.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: [GMCnet] Refrigerant: 134 vs Duracool [message #93253 is a reply to message #93227] |
Mon, 26 July 2010 03:47 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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| mcolie wrote on Sun, 25 July 2010 21:18 |
| k2gkk wrote on Sun, 25 July 2010 21:35 |
Was I imagining it or was somebody stating that Duracool molecules are quite a bit larger than those of 134a, thereby quite a lot less prone to leaks?
My Tundra 8 cu ft 12/120 Volt fridge appears that it is leaking refrigerant in the area of the connection between compressor and lines to the evaporator in the freezer compartment. There appears to be oil residue down near the compressor.
I'm wondering if Duracool might "plug" the leak?
Would using Duracool in the interior of a coach really be safe? This is the fridge I removed from my boat and if I can get the leak stopped I'll use it as a beer/pop fridge in the garage or put it into "Money Pit" if the fridge there turns out to be non-functional.
Thanks!
~ ~ ~ ~ ~ ~ ~ ~ ~
~ Mac Macdonald ~
~ Oklahoma City ~
~~ "Money Pit" ~~
~ '76 ex - P.B. ~
~ ~ ~ ~ ~ ~ ~ ~ ~
|
Mac,
"Would using Duracool in the interior of a coach really be safe?"
Yes, we are talking about a flammable gas. About the same quantity as a stove lighter. And most of it is no different than the LPG you have a big tank of already (but that stuff is not very pure).
As a guy that once designed refrigeration systems for laboratories, I have been trying to find out more about HC-12, but the information is not readily available.
HC-12 is a 21% isobutane(c4h10) and 79% propane (c3h8). Both might be larger molecules than R-134(c2h2f4), but I would not count on that to stop a leak. Epoxy might. I used to buy a special epoxy for sealing up holes made by people defrosting with a hard tool. I haven't purchased any in years, but it can't be that different and still be epoxy.
I would clean the area where you found oil real well and then put a layer of a good epoxy putty over it.
I don't know where the leak is in my reefer, but I have a pretty good idea. I'm going to used a light hydrocarbon as a cleaner and then coat the suspect area with a penetrating (very low viscosity during set) epoxy and then pull a hard vacuum on the system. This all has to wait as I am going to do when the Duracool shows up.
Matt
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I have a Blazer that has an R-134 leak. I have been looking for it with dye and a sniffer for several years. Every year it gets a little worse.
This year just on April 1 I found it completely empty. I vacuumed it and recharged it with R-134. In one month (May 1) it leaked enough that it quit cooling. So I decided to use the same approach that I use on Nitrogen filled tires. The claim is that Nitrogen will stay in the tires but regular when air will leak out. So I fill my tires with 78% nitrogen and let the rest of the stuff (21%oxygen) leak out. Over time I should have all nitrogen left. This approach has never worked for me. I had to add air to my airplane nose wheel today. Which reminds me, I need to order a new one. That one is 19 years old and just about worn out.
Back to the AC. In the beginning of May I added two cans of Duracool to my R-134 system on top of what R-134 was left in there. It cools acceptably and as of today (July 25th) it is still working. It is slightly over charged for Duracool but I assume the R-134 will continue to leak and reduce the over all charge amount. Based on my limited 2 month test the unit is still cooling and it is still over charged.
Maybe there is something to this molecule size thing.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Refrigerant: 134 vs Duracool [message #93331 is a reply to message #93266] |
Mon, 26 July 2010 16:09 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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| emerystora wrote on Mon, 26 July 2010 08:17 |
> it is still working. It is slightly over charged for Duracool but I
> assume the R-134 will continue to leak and reduce the over all
> charge amount. Based on my limited 2 month test the unit is still
> cooling and it is still over charged.
>
> Maybe there is something to this molecule size thing.
> --
> Ken Burton - N9KB
>
Yes, the larger molecules will definitely help stop leaks past seals,
O rings and porous hoses. However there is some thing else going on.
That is that Duracool (HC12a) operates at about 100 psi lower
pressure. The lower pressure means less leakage and longer compressor
life.
You would be much better taking out all of the R134a and using 100%
Duracool to get even lower pressures on the compressor and it will
also cool even better.
Emery Stora
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I figure at it's current rate of leakage all of the 134 ought to be gone by the end of the summer leaving only the Duracool in the system.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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