
75
Pre-commissioning and Maintenance
Due to our policy of continuous product innovation, some specifications may change without notification.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
MAINTENANCE
General Maintenance Schedule
1. Water Quality Control
• The heat exchanger is not designed to be disassembled, cleaned, and does not contain any replaceable parts. If the heat exchanger is not
usable, the entire exchanger must be replaced.
• To prevent corrosion or scaling, water quality must be controlled. Refer to the recommendations in Table 32 for minimum water quality
requirements.
• Use only anti-corrosion agents or corrosion inhibitor additives that do not contain chemicals which damage or attack 316 stainless steel and
ACR copper.
• Drain and replace the water / glycol mixture on a regular basis as needed. Frequency will depend upon the quality of the water treatment
program used.
Closed Type System
Effect
Circulating Water
Supplemented Water
Corrosion
1
Scale
1
Basic Item
pH (77°F)
7.0 ~ 8.0
7.0 ~ 8.0
●
●
Conductivity (77°F) mS/m
Below 30
Below 30
●
●
Chlorine ions (mg Cl
-
/ℓ)
Below 50
Below 50
●
Sulfate ions (mg SO
4
2
/ℓ)
Below 50
Below 50
●
●
Acid consumption (pH4.8) (mgCaCO
3
/ℓ)
Below 50
Below 50
●
Total Hardness (mg CaCO
3
/ℓ)
Below 70
Below 70
●
Calcium Hardness (mg CaCO
3
/ℓ)
Below 50
Below 50
●
Ionic-static silica (mg SiO
2
/ℓ)
Below 30
Below 30
●
Reference Item
Iron (mg Fe/ℓ)
Below 1.0
Below 0.3
●
●
Copper (mg Cu/ℓ)
Below 1.0
Below 0.1
●
Sulfate ion (mg SO42/ℓ)
Must not be detected
Must not be detected
●
Ammonium ion (mg NH4+)ℓ
Below 0.3
Below 0.1
●
Residual chlorine (mg Cl/ℓ)
Below 0.25
Below 0.3
●
Free carbon dioxide (mg CO2/ℓ)
Below 0.4
Below 4.0
●
Stability index
●
●
1
The “●” mark for corrosion and scale means that there is a possibility of occurrence.
Table 32: Minimum Water Quality Requirements.
2. Flow Rate Control
• The heat exchanger may freeze if water flow rate is insufficient.
• Check for a restricted strainer or if air is in the water piping system. Also measure the temperature and pressure difference between the
inlet and outlet to verify the flow rate is per specifications.
• If the temperature and pressure difference is above the specified range, the flow rate is insufficient. Immediately cease system
operation, locate the source of the problem and repair as needed. After any water circuit maintenance is preformed, always bleed air from
the water system at all installed air vents.
3. Antifreeze Concentration Management
• Use the manufacturer’s recommended type and amount of antifreeze. Do not use solutions with calcium chloride; these can corrode the
heat exchanger.
• Maintain antifreeze levels. If there is a drop in the amount of antifreeze, the heat exchanger may freeze. Ensure that the antifreeze is not
exposed to the atmosphere, and periodically measure antifreeze levels, adding as necessary.