Airedale Ultima Compact FreeCool 30kW - 450kW - Manual (Page 31)

Chillers ULTIMA COMPACT FREECOOL
Chillers
31
Technical Manual : 6259576 V1.2.0_02__2013
Performance Data
OPERATING LIMITS
Unit With Electronic Fan Speed HP Control (-20°C)
Minimum Ambient air DB °C
-20°C
Maximum Ambient air DB °C Refer to Capacity Data – DX Mechanical Cooling , on page 20
Minimum leaving water temperature °C +6C
Maximum return water temperature °C +20°C
1 Temperatures lower than those stated can be obtained with additional glycol.
2 For conditions outside those quoted, please refer to Airedale.
GLYCOL DATA For a given percentage of glycol in the system there are correction factors that need to
be applied, the following tables can be used as a guide.
CAUTION All free cooling units should use minimum 20% glycol concentration.
Ethylene Glycol Nominal Correction Factors
Glycol in System / Freezing Point ºC 20% / -9°C 30% / -15°C 40% / -23°C
Cooling Duty
Catalogue Data x by:
1.00 0.98 0.96
Input Power 1.00 0.98 0.97
Water Flow 1.00 1.09 1.12
Pressure Drop 1.00 1.29 1.48
Propylene Glycol Nominal Correction Factors
Glycol in System / Freezing Point ºC 20% / -6°C 30% / -12°C 40% / -20°C
Cooling Duty
Catalogue Data x by:
0.98 0.94 0.91
Input Power 1.00 0.98 0.97
Water Flow 1.00 0.99 0.99
Pressure Drop 1.08 1.22 1.35
Example UCFC150DQ-4/1 operating at 7/12, 30°C Ambient, 30% Ethylene Glycol
Catalogue
Figure Multiplier
Corrected
Figure
Cooling kW (refer to Capacity Data – DX Mechanical Cooling , on page 20) 146.1 x 0.98
30%
Ethylene
Glycol =
143.2 kW
Input kW (refer to Capacity Data – DX Mechanical Cooling , on page 20) 54.1 x 0.98 53.0 kW
Flow l/s calculated
(DX Mechanical Cooling kW)
7.49 x 1.09 8.16 l/s
 T x 3.9
Pressure Drop kPa (refer to Waterside Pressure Drops , on page 32) 146 x 1.29 188 kPa