Heeeeeeeeeeeeeeeeeeeelp

[elieprolb]

Heeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeelp.
I have a refrigeration project and I don't know anything.
I need to ask someone who knows a few questions. The presentation is due one Friday.

Let's say I found the required load and it is = 40 kW
Cold store condition = 2 degree C
Product is apples
Dry bulb temp = 36 degree C

How do I choose:
1. Refrigerant
2. Evaporating temperature
3. Refrigerant temperature (or is it the same as 2.)
4. Condensing temperature
5. Compressor power
6. Different temperature differences in the cycle
7. Equipment selection

Keep in mind this is a small college project. The teacher obviously doesn't know anything, so I'll accept an help.

thank you

[beenthere]

Moved to Refrigeration and Ice Making forum

[gary_g]

I have a refrigeration project and I don't know anything.....

.......The teacher obviously doesn't know anything.....

Sounds like you're wasting your parents tuition money.

[elieprolb]

Sounds like you're wasting your parents tuition money.

No
It's a public free college...
I would have enjoyed your help more than your non-funny jokes

[2story]

I would open some books like my copeland manual and to some research, why should we do your Homework for you?

[elieprolb]

I would open some books like my copeland manual and to some research, why should we do your Homework for you?

No. I'm actually reading two books but I'm not understanding everything. I don't need you to make my homework, I need a few hints if I'm allowed to call them so. I need catalogs for equipment selection, there is none in my books and the teacher haven't provided any.
I want to know the temperature of evaporation and condensation of different refrigerants so I can choose one. I also want to know where do I use the 40 kW load I calculated on my OWN and haven't asked YOU to do it !!!!!!!!!!!
Thanks for nothing

[seraaco]

I think it would be interesting to how you got that big number and can´t find a refrigerant type:confused::eek:

[HeyBob]

No. I'm actually reading two books but I'm not understanding everything. I don't need you to make my homework, I need a few hints if I'm allowed to call them so. I need catalogs for equipment selection, there is none in my books and the teacher haven't provided any.
I want to know the temperature of evaporation and condensation of different refrigerants so I can choose one. I also want to know where do I use the 40 kW load I calculated on my OWN and haven't asked YOU to do it !!!!!!!!!!!
Thanks for nothing



I think your skin needs to be a little thicker. You roll in here asking for help, the guys around here are testing you and you post like that. Your chances of getting help are going down hill fast.

So, now tell us something, are you a student at a college studying HVAC, is this a hypothetical question or do you really have a load of apples that need to be refrigerated?

[beenthere]

Hints:

When you did your load calc, you had to have a box temp. Your refrigerant should not have the compressor operating in a vacumm to attain that temp.

Virtually all manufacturers have catologs online that you can download. And see what their units BTU capacities are at the evaporator temp you need.

A single evaporator doesn't work in every appliaction.

Do you know if your box temp requires a defrost cycle.

Did you do your load calc based on an hour. Or based on a 24 hour day.

[Phase Loss]

how can you ask a question about system design and not know the bare bone basics?

You are trying to run before you can walk.

and you come off as an ignorant prick.

[icemeister]

Heatcraft refrigeration has an excellent manual for load calculation and equipment selection:

http://www.heatcraftrpd.com/resources/misc/H-ENGM0408.pdf

Choosing which refrigerant to use calls for a bit of knowledge of economics, environmental concerns and of course...experience. I suggest going with R404A as it's likely the best all around refrigerants for commercial refrigeration systems available today.

If you need to select specific equipment, Heatcraft has all the catalogs you'll need. Here's a condensed catalog form Bohn (one of Heatcraft's product lines):

http://www.heatcraftrpd.com/resources/catalog/BN-CC-1008.pdf

Good luck on your project. :)

[gatorfan9606]

like ice said theres so many sites out there that can get you very close to what you are looking for also emerson has an option called Product selection software check it out also good luck

[kerreckt]

Just about every equipment manufacturer has the info you need be it software or worksheets go to their website. Most the stuff is free to download.. You should spend your time at their sites and you will learn a great deal without having to ask anyone and put up with abuse for wanting the answers given to you. No one is really doing you any favors by giving the answers. Learning is a process that happens with effort and desire......usually in equal measures....good luck

[elieprolb]

thank you very much guys
I'm almost done

[man from trane]

Man do I feel dumb after reading that question. :o I'd just order a Kysor QM-5 and pipe it up to the header, throw the apples on the shelves and call it good.

I think my tech school ripped me off...:(

[A1 Burt]

Did you know that you can have apples at 29*F becous of the amount of suger in them for longer shelf life & there are other set up's you can do find out what R-H you need for the best product shelf life good luck:cool:

[elieprolb]

I presented my project yesterday and got Very Good...
thank you guys

[Poodle Head Mikey]

Apples have some particular storage requirements. None of which I can remember at the moment. Can't dry them out too much - can have them molding.

What is the difference between "cold store condition" and "dry bulb temperature"?

36 degree box could still use off-cycle defrost if you keep your coil TD low enough. That may give you humidity issues with apples though. What's the specified storage RH?

On the other hand you can add to your refrigeration-day by using a defrost. I would personally use a reverse-cycle defrost as it's easy, fast, cheap, and more fun, but that's just me.

What do you have available to cool the condenser?

BTW: What are you being graded on if the teacher doesn't know anything?

PHM
---------





Heeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeelp.
I have a refrigeration project and I don't know anything.
I need to ask someone who knows a few questions. The presentation is due one Friday.

Let's say I found the required load and it is = 40 kW
Cold store condition = 2 degree C
Product is apples
Dry bulb temp = 36 degree C

How do I choose:
1. Refrigerant
2. Evaporating temperature
3. Refrigerant temperature (or is it the same as 2.)
4. Condensing temperature
5. Compressor power
6. Different temperature differences in the cycle
7. Equipment selection

Keep in mind this is a small college project. The teacher obviously doesn't know anything, so I'll accept an help.

thank you

[Joe Harper]

Man do I feel dumb after reading that question. :o I'd just order a Kysor QM-5 and pipe it up to the header, throw the apples on the shelves and call it good.

I think my tech school ripped me off...:(

Yea, we have read your posts...We think you got ripped off! :D:D:D:)

[crackertech]

Yea, we have read your posts...We think you got ripped off! :D:D:D:)

man from trane this is comming from a guy that went reifer school on O.B.T ie
crack town.:rolleyes::D:D.BTW hows things going up their for ya Joe?

[Joe Harper]

man from trane this is comming from a guy that went reifer school on O.B.T ie
crack town.:rolleyes::D:D.BTW hows things going up their for ya Joe?

LOL :)

Actually Im working for an outfit in Lakeland. Lots of wonderful work to do. Its like being in a time warp sometimes....
BTW, only went to refer school for 4 days..I told the instructor he should keep teaching, since he would get fired at a real job. :eek:

[crackertech]

LOL :)

Actually Im working for an outfit in Lakeland. Lots of wonderful work to do. Its like being in a time warp sometimes....
BTW, only went to refer school for 4 days..I told the instructor he should keep teaching, since he would get fired at a real job. :eek:

Are you still doing supermarkets? Do you work for N.B in Lakeland?

[Poodle Head Mikey]

What did you come up with?

PHM
--------




I presented my project yesterday and got Very Good...
thank you guys

[Joe Harper]

I work for Johnsons, NB is a bad word around the shop. I do the occasional market here and there. I got us kicked out of sweetbay the other night. That problem existed before my time here.. I seem to be the ice machine guy now. Its not too bad. Its fairly quiet, I can hear what people are saying now, (thanks copeland:mad:) and most of the work is in restraunts that are climate controlled and full of pretty women. No complaints yet :)