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Randykissling
20-04-2010, 11:51 PM
Hi guys
I have a CRC reach in cooler The system has a leak. I want to change out the compressor.(Afraid it sucked in contaminents) What would you change the system to. Temp Im looking for is 36 to 40 degrees F. What should I flush the system with. Thank you ahead of time

hyperion
21-04-2010, 09:03 AM
R134a may be suitable, it should run on similar pressure to R12. There is a limited choice for flushing, especially if this is a capillary system. It may be best to purge with OFN to get any remaining contaminents out. Once you have purged a couple of times, then fit the new compressor, fit a liquid line drier and leak test, then give the system a good vaccing out and charge with R134a using the manufacturers charge weight as a guide. Run the unit on test and trim the gas charge if necessary.

monkey spanners
21-04-2010, 10:47 AM
I would use a drop in replacement for R12 instead of R134a, such as R49/R413A as it will work better with any residual mineral oil that is in the system from the old compressor. Charge weight is typicaly 80/90% that of the original R12 charge but you will need to watch it run down to set temp a few time to adjust the charge for best operation.
As Hyperion says, a good vac and a new drier, i might be tempeted to put one in the suction too if there is a lot of contaminants in the system.

Let us know how it goes :)

Randykissling
22-04-2010, 12:20 AM
I may put in hot shot does that take 80-90 pct charge also?
Thank you

One Man
22-04-2010, 04:08 AM
Yes sir Randy. I actually just charged an old R-12 system with Hot Shot today. The charging chart says tha you need 80% of a standard charge with R-414b (Hot Shot). The system is moving heat wonderfully and I'm pretty pleased.

nike123
22-04-2010, 04:44 AM
DuPont refrigerant _Replacement_Guide.pdf
http://www.mediafire.com/?z2ymtfykw2y