[Gmcnet] Duracool compatibility

[John Wright]

Actually Emory the Duracool site  says that the existing refrigerant  
must be removed before charging with Duracool.

See Below:

John

CHARGING INSTRUCTIONS

Using DURACOOL 12a® to replace R-134a is extremely easy. DURACOOL  
12a® is compatible with both mineral and synthetic oils found in both  
systems. You are able to use the oil that was originally installed in  
the system, mineral in old CFC-12 systems and synthetic oil in R-134a  
systems. We recommend that you use Duracool® A/C Oil Chill with OEM  
approved U/V Leak Detection Dye. Additional information on Duracool®  
A/C Oil Chill can be found by clicking on the A/C Solutions link from  
the navigation bar at the top of this page.

To replace CFC-12 with DURACOOL 12a® requires the removal of all  
existing refrigerant. Charge the DURACOOL 12a® using 35% of the  
original (CFC-12) charge weight listed on the system tag. eg; system  
tag calls for 40oz of CFC-12, use 14oz DURACOOL 12a®. Since DURACOOL  
12a® is compatible with the mineral oils there is no need to change  
or flush your system. DURACOOL 12a® will work with the existing  
components. Pull a vacuum to at least -10 in hg. If a vacuum pump is  
not available be sure to use Duracool® DuraDry™ to remove system  
moisture.

To replace R-134a with DURACOOL 12a® you must remove all the existing  
R-134a. Charge the DURACOOL 12a® using 40% of the original (R-134a)  
charge weight listed on the system tag. eg; system tag calls for 40oz  
of R-134a, use 16oz DURACOOL 12a®. Since DURACOOL 12a® is compatible  
with the synthetic oils there is no need to change or flush your  
system. DURACOOL 12a® will work with the existing components. Pull a  
vacuum to at least -10 in hg. If a vacuum pump is not available be  
sure to use Duracool® DuraDry™ to remove system moisture.

In Canada there are no requirements regarding the conversion of  
CFC-12 or R-134a to DURACOOL 12a®.

In the United States the EPA requires that systems using CFC-12  
refrigerants must be retrofitted to
R-134a prior to the use of DURACOOL 12a® .

CHARGING PROCEDURE

Recover any existing refrigerant charge into a suitable container,  
regulations vary by region and the recovery of existing refrigerant  
may need to be completed by an authorized technician. Leak test the  
system, if a leak is detected the system must be repaired prior to  
charging. DURACOOL 12a® is flammable and should only be leak tested  
with an electronic hydrocarbon leak tester, soap bubbles or  
fluorescent tracer fluid. If leaks are detected, ventilate the area,  
keep away from flames and repair the leak. After repair, continue  
with the charging procedure. Pull a vacuum of at least 25 cm Hg (10  
in Hg). If a vacuum pump is not available be sure to use Duracool®  
DuraDry™ to remove system moisture.
On Aug 9, 2008, at 10:52 AM, Gary Worobec wrote:

> Thanks Emery, that seems to make the most sense.
>
>
> Gary and Joanne Worobec
> Anza, CA
> 1973 23' Glacier
>
> ----- Original Message -----
> From: "Emery Stora" <emerystora at mac.com>
> To: <gmcnet at gmcers.org>
> Sent: Saturday, August 09, 2008 7:42 AM
> Subject: Re: [Gmcnet] Duracool compatibility
>
>
>> Gary - I have seen people add Duracool (HC12a) to an existing system
>> that already had R12 or R134a in it.  The Duracool site says that it
>> will do no harm.  However, since the Duracool provides a much lower
>> head pressure on the compressor and is more efficient in cooling and
>> at a relatively low cost, it makes much more sense to take out the
>> remaining R12 or R2134a and fill with Duracool.  If your system still
>> have refrigerant in it and has not had any air or moisture ingested
>> then you don't have to draw a vacuum.  You can bleed off the existing
>> refrigerant from the low pressure valve and fille with the Duracool.
>>
>>