multi-pressure system sizing

[Cotsy]

Hi all,

I am new to refrigeration and I am doing a project on a centralised refrigeration unit for a cold store with multiple evaporators working at different temps.. I have all my evaporators selected and I was just wondering where to go from there. Could anyone guide me in he right direction or suggest a book or guide to take me through the design and selection process?

[Josip]

Hi, Cotsy :)

Welcome to RE forums...


Hi all,

I am new to refrigeration and I am doing a project on a centralised refrigeration unit for a cold store with multiple evaporators working at different temps.. I have all my evaporators selected and I was just wondering where to go from there. Could anyone guide me in he right direction or suggest a book or guide to take me through the design and selection process?

...please search RE forums for..... suction pressure regulator......different evaporating pressures......

...long weekend in front of you;)....hope will be of some help.....

.....then come back with more questions...

Best regards, Josip :)

[US Iceman]

I am new to refrigeration and I am doing a project on a centralised refrigeration unit for a cold store with multiple evaporators working at different temps..


Since you are new I will be easy on you.;)

Are you planning on using one suction pressure to run all of the various evaporating temperatures?

Or,

Are you using a specific suction pressure for each evaporating temperature range? (hint: multiple evaporating temperatures = mulitple suction pressures :cool:)

[Core4 Guy]

Hi all,

I am new to refrigeration and I am doing a project on a centralised refrigeration unit for a cold store with multiple evaporators working at different temps.. I have all my evaporators selected and I was just wondering where to go from there. Could anyone guide me in he right direction or suggest a book or guide to take me through the design and selection process?

Cotsy,

First, I sugggest you do something. Draw out your system into suction temperature groups and select a cost effective suction temperature for each group. Then select each rooms control design (either on / off or controlled suction temperature), then select defrost methods(hot gas, cool gas, airover, water, electric) then select your evap coils based on those conditions. Everything I have suggested is very important depending on what your storing (hops, grapes, beer, lettuce, case goods) and how long it is to be stored. All products have different requirements. Then you need to design the system...Ouch. I usually have a system design in mind when I'm doing everything else.

I assume that you have a refrigeration partner in this and are just looking for ideas or you are just giving us a hard time. If you havn't had much experience in process refrigeration I suggest you read quite a few books and look at some different sites in your area. There are a million ways of doing things but the easiest is usally not the most efficient.

Four books helped me out alot, Industrial Refrigeration Handbook (http://www.amazon.com/Industrial-Refrigeration-Handbook-Wilbert-Stoecker/dp/007061623X/ref=sr_1_7?ie=UTF8&s=books&qid=1203868132&sr=1-7) by Wilbert F. Stoecker, Ashrea Fundamentals and Refrigeration, and IIAR Handbook. A lifetime of friends (engineers) and expierience (as a service mechanic) in the industry was a better source for me.

All have good information but you must pick and choose as you learn. There are more steps but you can do it.

Please also understand once you design a system for a customer you take ownership of that design and are responsible for it.

Good luck.

[Cotsy]

Thank you all for your help. I shall get back to you when I have made some progress. :confused: