Daikin EUWAB10KBZW1, Руководство по обслуживанию

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Pre-Test Run Checks ESIE11-02
4–6 Part 4 – Commissioning and Test Run
3
1
4
5
Calculation of the
minimum water
volume The calculation method below is based on the fact that the water volume in a chiller should be large
enough to prevent the compressor from excessive cycling. Sufficient water volume gives a certain
inertia to the system, so that:
■
Water (or glycol) temperature does not drop too fast when the unit turns ON.
■
Water (or glycol) temperature does not rise too fast when the unit turns OFF.
with:
Water quality The table below contains the required water quality specifications.
Notation Dimension Description Default
V [m³] Required system volume —
Q [W] Cooling capacity at the lowest capacity
step of each chiller in the system —
t [s] Minimum cycling time allowed by the com-
pressor 240 s
ρ
[kg/m³] Specific mass of the fluid
ρ
water
= 1000 kg/m³
d [K] Thermostat step difference d
inlet water control
= 3 K
C
w
[J/kgK] Specific heat capacity of the fluid C
w, water
= 4186 J/kgK
0,5 x Q x t
V = [m³]
2 x
ρ
x d x C
w
Evaporator water Heated water (low temperature)
Tendency if out of
criteria
Circulating
water (< 20°C) Supply water Circulating water
(20°C-60°C) Supply water
Items to be checked
pH at 25°C 6.8~8.0 6.8~8.0 7.0~8.0 7.0~8.0 Cor scale
Electrical conductivity mS/m
(at 25°C) < 40 < 30 < 30 < 30 Cor scale
Chloride ion
mg Cl
-
/l
< 50 < 50 < 50 < 50 Corrosion
Sulphate ion
mg SO
4
2-
/l
< 50 < 50 < 50 < 50 Corrosion
M-alkalinity (pH 4.8) mg CaCO
3
/l < 50 < 50 < 50 < 50 Scale
Total hardness mg CaCO
3
/l < 70 < 70 < 70 < 70 Scale
Calcium hardness mg CaCO
3
/l < 50 < 50 < 50 < 50 Scale
Silica ion mg SiO
2
/l < 30 < 30 < 30 < 30 Scale
Items to be referred to
Iron mg Fe/l < 1.0 < 0.3 < 1.0 < 0.3 Cor scale
Copper mg Cu/l < 1.0 < 0.1 < 1.0 < 0.1 Corrosion
Sulphide ion
mg S
2-
/l
Not detectable Not detectable Not detectable Not detectable Corrosion