r408 a

[cliffjb]

hi
can anyone tell me were i can get superheat and subcooling charts for the above gas and what the ideal temps are in a freezer room .

[nando]

coolpack but a freezer that works with this gas, it is time to change with the new gas

[cold.man]

R408 is no longer in use
there are threads on this site with people using R408 and R22 why are people using these gases they should be retrofitting these systems.
if you have broken into this system it will require retrofitting.

[Brian_UK]

R408 is no longer in use
there are threads on this site with people using R408 and R22 why are people using these gases they should be retrofitting these systems.
if you have broken into this system it will require retrofitting.

Maybe not in South Africa..??


++

PT Chart ...

http://www.refrigerants.com/pics/ptchart.pdf

[cliffjb]

HI in sa we still use r22 in most of our commercial applications as well as 406 and 408,what i was asking is if my room is at minus 20 degrees c my vapour pressure at the compressor should be around 26 psi what then should the temp be on the suction line at the compressor and at the exit of the evaporator .what should they be?? for the superheat to be ideal

[texas64]

Suction line temp at compressor is not where you measure superheat. You should measure at the evaporator outlet. This is probably a low temp system, so 6 to 8 degree superheat when the box is at temp. Suction line temp at compressor can vary depending on heat picked up travelling to compressor. Usually 40 degrees Fahrenheit or lower is ideal for compressor cooling.

[cliffjb]

thanks texas
is there a chart that tells you the superheat should be 6 to 8 how do you determain what the correct superheat should be ,im not asking how to measure it but what the correct temps should be for different gasses and systems

[texas64]

Check this out from Sporlan---- http://sporlanonline.com/10-9_32011.pdf

Sporlan is the number one manufacturer of refrigeration valves and products.

http://sporlanonline.com/tevs.shtml

Hope it helps...

James

[cliffjb]

thanks will do

cliff