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vinic
03-01-2005, 01:34 AM
Being new to both refrigeration and this group, I have a few very basic questions to ask. I spent the last hour or so gleening over previous post and could find nothing that directly answered my questions, nor provided leads to answers.

First and foremost is the identification of a compressor that was recently purchased. I believe it's an older model that's been sitting around awhile, never used. The information I have is:

Prestcold Model C500R1370K12M
5 HP
220V/3 PH

So far, attempts to dig up more information on this unit from online sources, (mainly the Copeland website) have produced nothing. Next step is to contact the local distributor, but I thought possibly someone in this knowledgeable group might either know, or have a lead to more info!?

Now the project description. I have a room, ~30' x 16', that I'd like to cool down to ~ 23F, or as close to that as possible. From what I can tell, two more components (at least) are required: a condenser and an evaporator.

Is there a range for the size of these other components to match up with the compressor? If so what is that range? If not what size of a condenser and evaporator is needed?

I'm presently downloading an etext that was posted elsewhere on this list. Any other resources (online or otherwise) for a raw newby that would like to have a practical, if limited, knowledge of this field?

tia,

Clyde Gill

Peter_1
03-01-2005, 07:44 AM
Following is a rough estimate which will be pretty close to the reality.
The 500 in the number stands for 5 HP.
This machine will give +/- 10 kW at -10C (23 F) on R134a
So look for an evaporator which gives 10 kW at -10 C and the DT according the desired humidity level.
A condensor of 13 to 15 kW at a DT of 10 K.

That's all.

On the other hand , if you need more info then we need more info from you: what outside temperatures can you expect, in what size of room will you install this unit, what is the desired humidity, what will you store in it, what sort of gas will you use,..

vinic
03-01-2005, 01:48 PM
Thanks for the reply Peter. This gives me a good starting point.

To fill in some details about the project:

The room is 30 ft by 16 ft with half the area being 10ft tall, the remainder has a slanted cathedral style ceiling of 18ft on one side and 14 ft on the other. Insulation is decent on one side (north) and extreme on the other side (south side is earth).

The room was designed specifically for cold stabilizing wine by utilizing mother nature. A large door provides isolation from the main cellar, and another door provides access to ambient temperatures, which can easily dip into negative Farenheit during the peak of the winter. Presently, there's about 7,000 gallons of wine in the room and, with proper tank sizing, can hold upwards of 10k gallons.

The first objective is to augment mother nature. With ever increasing warming winters, I'm looking into alternative ways of getting the wine stable. Also, it would be nice to get the wine stable earlier in the season. The room is generally full by the beginning of November, but our outside temperatures typically don't tend to fall until Janurary. So we're looking at dropping average temps in the 40-50F down to the lower 20's range.

Second objective is to lower temperatures during the time of fermentation. Wine temps in the tanks we use (~500 gallons) will climb to 70F+, and it would be best to keep them at 50F. I know this is not a very efficient way to cool tanks, but at this time, it is the most feasible for our operation/budget. Outside temperatures are typically in the 80-90F during this fermentation period.

As a final note, I do intend to bring in some professional assistance before going much farther with the project. But before doing so, I wanted to educate myself a bit about what was going on.

Thanx again,

Clyde Gill

Peaceful Bend Vineyard (http://www.peacefulbend.com)

chemi-cool
03-01-2005, 03:58 PM
Hi Clyde,

I have done a few of these so I have some questions for you.

For fermentation, we use SS tanks with double walls where cold water are coming in from a chiller outside.

For keeping the bottles in the right temp and humidity, a small cooling unit is used as the temps are just under AC temp. 18C.
Humidity is kept by ultra sonic humidifier .

Why do you want to cool all the space when you can only cool the the tanks?

Can you post some pictures?

Chemi :)

vinic
03-01-2005, 04:46 PM
Hi Clyde,

I have done a few of these so I have some questions for you.

For fermentation, we use SS tanks with double walls where cold water are coming in from a chiller outside.

For keeping the bottles in the right temp and humidity, a small cooling unit is used as the temps are just under AC temp. 18C.
Humidity is kept by ultra sonic humidifier .

Why do you want to cool all the space when you can only cool the the tanks?

Can you post some pictures?

Chemi :)

Plans are to eventually install a state-of-the-art facility, and this will incoporate a glycol system along with jacketed tanks. But for now, this is a retro-fit and none of the tanks we have are jacketed. As noted before, I know this is not the most efficient way of going about this function, but it's our only choice, plus we will be assisted by some cooler ambient temperatures (hopefully!).

We have been able to achieve cold stability of the wine in the past just by using ambient temperatures. In '99 it was a little difficult, as the temps did not stay cold for long, but we sneaked by. Today, the high temp is in the upper 60's and I'm starting to become a little concerned. Warm winters happen around here, but it's not very typical. Below freezing is more common this time of year. Even in a normal winter, it would be nice to have at least some of the wine ready to bottle earlier in the season.

Humidity for bottle storage is not a issue. We now use synthetic closures to avoid cork taint, and an added benefit is the lack of humidity requirements for storage. Humidity for the barrel storage is not much of an issue either... if there's anything we have in the Midwest US, it's humidity!

As for pictures, I can snap a few and put them up. In the mean time, here's some pictures of a roofing project a couple years back that created the "cathedral" section of the cellar:

Roof Project (http://misn.com/~peaceful/progress2.htm)

Regards,

Clyde Gill

chemi-cool
03-01-2005, 07:50 PM
Hi Clyde,

I get your point.
Here in the desert we produce more and more wine and its growing all the time.

Some of the winers, keep the bottles in cellars dug underground and do not use any cooling as from one meter below ground level, temps do not change from winter to summer.

Now I see that you know the business so I'm sure it will be OK.
Check the compressor for type of refrigerant and change the oil .

Chemi :)

Peter_1
03-01-2005, 11:15 PM
Hey all...Stop helping vinic :D
He ow us all some bottles of wine first. :p

vinic
04-01-2005, 11:18 PM
Hey all...Stop helping vinic :D
He ow us all some bottles of wine first. :p

No problem Peter. Just come on by the winery!! ;)

Regarding Chemi's note: the unit I purchased is an older unit that has never been used. I'm assuming that it will have 'fresh' oil but no refrigerant.... is that a valid assumption?


Here's the compressor:

http://tinyurl.com/4oj2x

I hope to be able to pick it up later this week.

regards,

clyde

chemi-cool
05-01-2005, 05:37 AM
Hi Clyde,

Hey, thats a good price for a semi hermetic compressor. I'd buy 10 off you for that price.

Anyway, if the compressor was standing for a long time, lets say a year, then the oil in it is not good anymore.

Refrigeration oil, (I believe its mineral oil in your case ) shoud be changed before runing the machine.

I was asking which refrigerant is it made for?

Chemi :)

Peter_1
05-01-2005, 07:56 AM
Most probably for R12.
If machine is still under pressure when he receives it, then i shouldn't be afraid about the oil.
If he changes it to ester oil, he can use ot on R134a.
The quality only degrade with air and moisture while running.
You also need an Oil Safety Device, there is an oilpump on it. his OSD will cost you more then you paid for the compressor :D

Now you have only to look on Ebay for a receiver an evaporator and a condenser.
And someone to hook this all up because this isn't that easy as it looks.

Like Chemi said , you paid only the price for scrap (if you understand what I mean in my broken English)

chemi-cool
05-01-2005, 05:52 PM
Hi Clyde.

I've enlarged the pictures and I saw oil marks at the oil pump side. This is a sign that the compressor have been working.

Ask the seller to copy the name plate. It might be different then what it says on the box.
Please let us know what you got.

Chemi :)

chillin out
05-01-2005, 11:37 PM
Hi Clyde

I agree with chemi i also enlarged the pictures and i thought it looked like a arctic circle compressor that has been used.
This comp is way too technical to be used, you will need so many other parts, cond, cond fan, liquid receiver, pressure switches, oil seporator, sump heater, ..... the list goes on and on. Then you need an evaporator, piping, control box and many other small parts.

Go buy a kit from a supplier or go see a system thats for sale privately and see its working before you dissmantle it.

vinic
06-01-2005, 03:23 AM
Looks like it'll be early next week when I pick this unit up. Interesting to hear the comments from people who know what they're looking at. How I came about buying this is quite a comical side note. That afternoon I had been setting up a wireless network for my father, and at one point it dawned on me that this auction that I'd been following was about to close. Loading the window while describing it to my dad, he commented on how he disliked the proxy bid system on eBay... to which I replied, "no, this is a cool thing, you want to be able to place a low bid, then have a high-as-you-care-to-go proxy bid in place... watch I'll show you". The bid was at $29. I had done some research, but could not come up with an exact figure for the value of a compressor this size. I was guessing in the several hundred dollar range. I'd already emailed the seller and found out that I could pick it up, so there was no danger of getting trapped with a high shipping fee.. he's only about 2 hour drive from here. Anyway, I put in a bid for $30 assuming that the guy who had bid $29 had a proxy bid going... suddenly, I was highest bidder with less than a minute left. Of course I immediately placed a proxy bid at $50 (in hind site, this was probably way too low), but nobody was around and I ended up 'winning' the bid :eek: . I figured worse comes to worse, I might be able to scrounge a 5 hp motor off this thing!? Best case scenario, you all help me set things up, I hire my local refrig man, and I'm chilling my wine a bit earlier than usual!

I post back how things go, and get some pics up of the unit when it gets here.

Thanks all (so far). The feedback has been nothing short of great.

I've heard several refrigerants discussed here. Is there a limited choice as to what can be used in a compressor like this? After reading a bit, there are quite a few more refrigerants going around these days than I had imagined... including CO2!?




clyde