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Rusrav
20-03-2009, 11:57 PM
Hi everyone!
I produce different frozen foods in New York and have been using regular walk in boxes for the last ten year, finally one month ago I bought a spiral freezer from Italy, they give me the box, spiral conveyor, evaporators, washing system for the belt and controls and of corse they install the whole think but the compressor is not included I have to buy it locally and install it. So I have contacted three different refrigeration companies and submitted them all the technical information that Italian company have sent me in connection with the refrigeration system, after a week I have received the quotation from the ref. companies and to my big surprise they all quoted me very different thinks, one said I need only 20 hp unit another said I need some kind of double system which will cost me somewhere 50k (just the unit, installation is another 20k) and the third company said that I need two 30hp units. I don't know what to do, and don't get me wrong I don't mind paying more its just I want to make sure that this system is going to work, so I found this website and hope someone will help me understand what I need. Bellow is the information that the Italians sent me, this is for one evaporator and the system will have two of them.
Thank you very much!


Operating ModeDirect Expansion Unit type Airmax II Model ILB562G

Type of calculation
Required Capacity 20.00 kW Margin 10.1 %
Calculated capacity 22.02 kW

Dimensions

Length 2580.0 mm Standard unit weight 330.0 kg
Height 1186.0 mm
Depth 960.0 mm
Packing Crate Shipping Volume 4.0 m³

Thermal Data

Refrigerant R404A
Air Temperature -35.0 °C / -37.4 °C
Relative humidity 80.0 %
Evaporating Temp. -42.0 °C
Temperature difference 7.0 K

Fan data

Air flow: 6.061 m³/s Number of Fans 2
Air throw 45.9 m Fan diameter 560.0 mm
Rotation speed 1220 rpm Voltage 400V
Total Nominal Power 2000.0W Power Supply 3pH
Total Nominal current(2) 3.60A Connection D
Total FLC (-30°C) 4.32 A
Sound Pressure Level (5.0 m) (1) 71 dB(A)
Sound Power Level 84 dB(A)

Coil data

Tube material Copper Fin material Aluminium
Fin Spacing 12.0 mm Number of Circuits 20
Surface 155.7 m² Internal Volume 45.5 litres
Connections (In-Out) 35 - 64mm ConnectionSide Left - Standard

Frame and casework Standard
Case material Galvanized steel painted

NOTES

(1) By using the absorption area of 100m2 at distance of 5 m (Sabine)
(2) Nom. current at Tair=20°C. Variations occur due to different voltage or Tair

chemi-cool
21-03-2009, 07:22 AM
The Italians are very clear, you need a condensing unit for low evaporation application,

Capacity at -42°C evaporator temp, 22 KW
It is not unusual.

For these low temp, I would suggest to use R-507.

Rusrav
21-03-2009, 04:39 PM
Thank you for your suggestion but what I need to know is which compressor to buy (hp)
Thank you

chemi-cool
21-03-2009, 08:19 PM
OK, a 30 HP Copeland will get you there.
That is if you can keep a low head pressure.
These are very low evaporating temp for a semi hermetic compressor. you will need it with a liquid injection cooling and vertical cooling fan.

Good luck.