refrigerant for use at an outside temperature of -60°F / -50°C

[H2genius]

hi all !

sorry my first post .... sorry for that .. but glad i found this group!

i am looking for a solution for a refrigerant to use in the following conditions
for a system to be able to work reliably
provide heating at ambient outdoor conditions of -60°F / -50°C

to cool down a system that operates at up to 300°F/150°C to ambient temperature of 95°F/35°C


application is heat pump + conventional AC with inverter technology

how to prevent freezing of the condensor / evaporator or piping system?

suggestion are welcome.

thank you all for taking the time to read my post!

looking forward to receiving your suggestions!

H2genius