What should I look for in a compressor for a chiller?

[afireinside]

I'm gona use a 20' 1/4" OD evap and condensor and the captube sizing I have saved somewhere. Refrigerent will be R290 propane (where can I get pure enough to use propane?)
I found this on ebay:
"NEW - UNUSED
SAMSUNG SK390C-LOZ REFRIGERATION COMPRESSOR.

115 volt, 60 Hz, Single phase.
For use with R12 refrigerant and rated at 1211 BTU.
The unit is UL approved.
This is a great replacement unit for any refrigerator that needs a hermetic unit and uses R12 refrigerant."

It looks intresting but the refrigerator part doesent sound to good
Where else can I look for compressors other than at a junk yard/old ACs?
I want a quiet low temp compressor. I'm 13 so its not like I could hop in my car and drive around looking for old freezers

[water_cooler 20]

thats about the same btu as the compressor i used to have on my water chiller and it worked pretty good and was quiet

[afireinside]

up up up

[NesQuiK]

me too , im only 15 . i dont have a car and mom doesnt like my project but ill still do it

[afireinside]

SCORE! I found 3 copeland 1/3 HP 5510 BTU R12 units

[kommando]

Lucky bastard, there is a fridge shop that have thrown at some ing huge frige with this masive compressor. Might ask whats up with it and if it works then ill hack away the compress and use it

[lalPOOO]

If its a fridge shop, I don't think they'd throw away a working fridge, they'd probably just fix it

[kommando]

Nah its some huge fridge thing, ill ask if it works one day.

[Miles_Teg]

afireinside,

guys, plz correct me if I'm wrong, but...
BTU/h and horsepower are both ways to express the same thing, cooling capacity, right? Then something must be wrong with the info afireinside mentions about the compressors he found. 5510 BTU/h and 1/3 hp do not match each other.

- 5510 BTU/h = 2.1 hp = alot, these compressors are used for A/C purposes, and usually work with R22 / R404 / R507.
- 1/3 hp = 840 BTU/h = average for large domestic fridges, usually for R12 / R134a.

Again, I'm still novice in the field, so do correct me if I'm wrong.

[Gary Lloyd]

BTU and horsepower are not the same thing. Just by coincidence, in an air conditioning application, 12000 BTU uses roughly 1 HP. So a 12000 BTU A/C compressor is about 1 HP. As evap temp drops, the BTU drops, so in a low temp application, a 1 HP compressor pumps a lot less than 12000 BTU.

[Miles_Teg]

Gary,

Hmm, so I see. So if I get this correctly, the BTU rating is related to evaporating temperature, while the HP rating just shows how strong a given compressor is (as in what pressure it can build).

If I'm getting this correctly, there must be a certain temperature at which compressors receive their BTU rating, right? (as it's fluctuating by temperature influence). Lemme guess, you know that temperature this is, right?

Edit: Typo's