Refrigerants

[GBRD]

Which refrigerant is better R404A or R134A for Blast Freezer application?

[PVA]

Which refrigerant is better R404A or R134A for Blast Freezer application?

Dear GBRD,

In generaly refrigeration system for Blast Freezer is system with low temperature as -30...-40C, and in the past R404 is used only for low temperature, so if you need -40 - you should use R404.
The boiling point at atmospheric pressure for R404 is -46,7ºC, and the boiling point at atmospheric pressure for R134 is -26,4ºC, so if you want below -26,4ºC you will have vakuum in system and you will have air after some times.

Sorry for my bad English.

[GBRD]

Thank you PVA......your english is actually good.

[moideen]

Dear GBRD,

In generaly refrigeration system for Blast Freezer is system with low temperature as -30...-40C, and in the past R404 is used only for low temperature, so if you need -40 - you should use R404.
The boiling point at atmospheric pressure for R404 is -46,7ºC, and the boiling point at atmospheric pressure for R134 is -26,4ºC, so if you want below -26,4ºC you will have vakuum in system and you will have air after some times.

Sorry for my bad English.

hi pva,you are correct, at present R404a is excellent for ultra low temperature applications.r-134a is not recommended for use in systems where the saturated suction temperature is below-10f.

moideen-dubai

[PVA]

To moideen>>>>
Thanks for your complement and correction!

[Lodiev]

Dear GBRD,

IThe boiling point at atmospheric pressure for R404 is -46,7ºC, and the boiling point at atmospheric pressure for R134 is -26,4ºC, so if you want below -26,4ºC you will have vakuum in system and you will have air after some times.

Sorry for my bad English.

Yes thats the big factor air and the Head pressure is the second. Make sure that the Kw r heat transfer of the condenser is correct for the compressor and cooling kw r of the plant so that u do not struggle with hi discharge temperature on the compressor's heads and to hi liquid temperature after the conversion. Also make sure with the compressor manufacturer that the compressor's suction and discharge valve plates can cope with the gas ( port size of the valve's) to prevent valve plate failure,and carbonizing of compressor oils.