Daikin EWAD620-C17C-SS, Руководство по обслуживанию

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General Outline ESIE10-01
1–74 Part 1 – System Outline
3
11
4
5
Q
Mixture Water and Glycol - Evaporator leaving water temperature < 4°C
• Depending on the type and percentage (%) of glycol filled in the circuit (see table "Minimum
glycol percentage for low water temperature" on page 1–72 and table "Minimum glycol per-
centage for low air temperature" on page 1–72 and table "Correction factors for water and gly-
col mixture" on page 1–73).
• Depending from the evaporator leaving water temperature (see table "Correction factors for
low evaporator leaving water temperature" on page 1–72).
• Multiply the Cooling Capacity, the Compressor Power Input by the Correction factor of table
"Correction factors for low evaporator leaving water temperature" on page 1–72 and table
"Correction factors for water and glycol mixture" on page 1–73.
• Starting from this new value of Cooling Capacity, calculate the Flow Rate (l/s) and the Evapo-
rator Pressure Drop (kPa).
• Now multiply the new Flow Rate and the new Evaporator Pressure Drop by the Correction
Factors of table "Correction factors for water and glycol mixture" on page 1–73.
Example
Unit Size: EWAD650C-SS
Mixture: Water
Working Condition: ELWT 12/7°C – Condenser inlet air temperature 30°C
Cooling capacity: 681 kW
Power Input: 205 kW
Flow Rate (
Δ
t 5°C):
32.54 l/s
Evaporator pressure drop: 87 kPa
Mixture: Water + Glycol 30% (for a low evaporator leaving temperature of
-1/-6°C)
Working Condition: ELWT -1/-6°C – Condenser inlet air temperature 30°C
Cooling capacity: 681 x 0.613 x 0.972 = 406 kW
Power Input: 205 x 0.870 x 0.986 = 176 kW
Flow Rate (
Δ
t 5°C):
19.40 l/s (referred to 406 kW) x 1.074 = 20.83 l/s
Evaporator pressure drop: 39 kPa (referred to 20.83 l/s) x 1.181 = 46 kPa