Firstly,calculate the amount of cooling required together with relevant losses,pull down times etc.The required temperature will then determine the refrigerant to use,at minus 40C you will be very close to the limits of single stage systems and may be looking at cascade.From then on its just a case of sizing the equipment,start with the compressor,that will determine condenser type size,and then evaporator.Oh and a good refrig guy to get it all to work.........

Hi Vidya,

You have a two prong problem here, your compressor and your cold storage

For your Bitzer compressor application go to www.bitzer.de ,you can browse what you want to know.

For your cold starage panels, reveiw its design application. At 12 C, if your using 100 mm thick polysterine (STYROPOR) is enough insulation.

At -20 its not enough, at -40 hmmm not a chance, beside at this temp you need floor insulation with moisture barrier and ground ventillation, etc..(insulation for the heat will not wonder, in to out and out to in, moisture barrier to prevent moisture from sipping in and frost, it can buckle up your floors and ventillation for stability during expansion and contraction because of temp difference.)

Theres a lot of details to consider in designing the system, besides the math. And if you are new to this field you have a lot of lesson to learn. Frankly and honestly I tell you, better ask a help in redesigning the the system to avoid head ache in the future.

best regards,