Thermal Care NQ Series, Руководство по установке и эксплуатации

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sensing, measurement and treatment needed for
satisfactory performance and life. The
recommendations of the specialist may include
filtration, monitoring, treatment and control devices.
With the ever-changing regulations on water usage
and treatment chemicals, the information is always
up to date when a specialist in the industry is
involved. Table 20 shows the list of water
characteristics and quality limitations.
Table 20 – Fill Water Chemistry Requirements
Water Characteristic Quality Limitation
Alkalinity (HCO
3
-
) 70-300 ppm
Aluminum (Al) Less than 0.2 ppm
Ammonium (NH
3
) Less than 2 ppm
Chlorides (Cl
-
) Less than 300 ppm
Electrical Conductivity 10-500µS/cm
Free (aggressive) Carbon
Dioxide (CO
2
)†
Less than 5 ppm
Free Chlorine(Cl
2
) Less than 1 PPM
HCO
3
-
/SO
4
2-
Greater than 1.0
Hydrogen Sulfide (H
2
S)* Less than 0.05 ppm
Iron (Fe) Less than 0.2 ppm
Manganese (Mn) Less than 0.1 ppm
Nitrate (NO
3
) Less than 100 ppm
pH 7.5-9.0
Sulfate (SO
4
2-
) Less than 70 ppm
Total Hardness (dH)k 4.0-8.5
* Sulfides in the water quickly oxidize when exposed to air,
requiring that no agitation occur when taking a water sample.
Unless tested immediately at the site, the sample will require
stabilization with a few drops of one Molar zinc acetate solution,
allowing accurate sulfide determination up to 24 hours after
sampling. A low pH and high alkalinity cause system problems,
even when both values are within the range shown. The term pH
refers to the acidity, basicity, or neutrality of the water supply.
Below 7.0, water is considered to be acidic. Neutral water contains
a pH of 7.0.
† Dissolved carbon dioxide calculation is from the pH and total
alkalinity values shown below or measured on the site using a test
kit.
Dissolved Carbon Dioxide, PPM = TA x 2
[(6.3-pH)/0.3]
where TA =
Total Alkalinity, PPM as CaCO
3
Table 21 - Recommended Glycol Solutions
Chilled Water
Temperature
Percent Glycol
By Volume
50°F (10°C) Not required
45°F (7.2°C) 5 %
40°F (4.4°C) 10 %
35°F (1.7°C) 15 %
30°F (-1.1°C) 20 %
25°F (-3.9°C) 25 %
20°F (-6.7°C) 30 %
CAUTION: When your application requires the
use of glycol, use industrial grade glycol
specifically designed for heat transfer systems
and equipment.
Never use glycol designed for
automotive applications. Automotive glycols
typically have additives engineered to benefit
the materials and conditions found in an
automotive engine; however, these additives
can gel and foul heat exchange surfaces and
result in loss of performance or even failure of
the chiller. In addition, these additives can
react with the materials of the pump shaft
seals resulting in leaks or premature pump
failures.
WARNING: Ethylene Glycol is flammable at
higher temperatures in a vapor state. Carefully
handle this material and keep away from open
flames or other possible ignition sources.
Step 3 - Check Condenser
There are three possible types of condenser present
in the chiller: Integral air-cooled, water-cooled, and
remote air-cooled. It is important to verify the chiller
will have adequate condenser cooling for proper
chiller operation.
Intergral Air-Cooled Condenser Check
Make sure the chiller is properly installed as
described in the mechanical installation section of
this manual. Check to make sure the chiller
condenser is clear of obstructions and has at least 36
inches of open air on the air inlet and outlets for
proper airflow.
Water-Cooled Condenser Check
Check the condenser water lines to make sure all
connections are secure. Make sure sufficient
condenser water flow and pressure are available, the
condenser water supply is turned on, and all shut-off
valves are opened.
Remote Air-Cooled Condenser Check
Check the refrigerant lines to make sure all
connections are secure and that a proper evacuation
of the chiller, the field piping, and the remote
condenser has occured. Verify the refrigeration
piping has been installed as descibed in the
installation section of this manual. Check the remote
condenser main power and control wiring to ensure
all connections are secure.