Installation of Indoor Unit   
Water Quality
Water quality should be complied with EN 98/83 EC Directives. Requirement  for resolved chemical
ingredients is following table. Detailed water quality condition  can be found in EN 98/83 EC Direc-
tives.
  Parameter                                                      Value
  Acrylamide                                                  0.10 μg/l
  Antimony                                                       5.0 μg/l
  Arsenic                                                            10 μg/l
  Benzene                                                        1.0 μg/l
  Benzo(a)pyrene                                        0.010 μg/l
  Boron                                                            1.0 mg/l
  Bromate                                                          10 μg/l
  Cadmium                                                       5.0 μg/l
  Chromium                                                       50 μg/l
  Copper                                                          2.0 mg/l
  Cyanide                                                          50 μg/l
  1.2-dichloroethane                                        3.0 μg/l
  Epichlorohydrin                                           0.10 μg/l
  Parameter                                                      Value
  Fluoride                                                         1.5 mg/l
  Lead                                                                10 μg/l
  Mercury                                                         1.0 μg/l
  Nickel                                                              20 μg/l
  Nitrate                                                            50 mg/l
  Nitrite                                                          0.50 mg/l
  Pesticides                                                    0.10 μg/l
  Pesticides — Total                                      0.50 μg/l
  Polycyclic aromatic hydrocarbons             0.10 μg/l
  Selenium                                                        10 μg/l
  Tetrachloroethene and Trichloroethene        10 μg/l
  Trihalomethanes — Total                             100 μg/l
  Vinyl chloride                                               0.50 μg/l
• If the product is installed at existing hydraulic water loop, it is important to clean hydraulic pipes to re-
move sludge and scale.
• Installing sludge strainer in the water loop is very important to prevent performance degrade.
• Chemical treatment to prevent rust should be performed by installer.
38 Air-to-Water Heat Pump
Frost protection
In areas of the country where entering water temperatures drop below 0 °C, the water pipe must be
protected by using an approved antifreeze solution. Consult your AWHP unit supplier for locally
approved solutions in your area. Calculate the approximate volume of water in the system. (Except
the AWHP unit.) 
And add six litters to this total volume to allow for the water contained in AWHP unit.
1. Use only one of the above antifreeze.
2. If a antifreeze is used, pressure drop and capability degradation of the system can be
occurred.
3. If one of antifreezes is used, corrosion can be occurred. So please add corrosion inhibitor.
4. Please check the concentration of the antifreeze periodically to keep same concentration.
5. When the antifreeze is used (for installation or operation), take care to ensure that antifreeze
must not be touched.
6. Ensure to respect all laws and norms of your country about Anti-freeze usage.
 
Antifreeze type
                                                          Antifreeze mixing ratio
                                                              0°C              -5°C            -10°C           -15°C           -20°C           -25°C
               Ethylene glycol                       0%               12%             20%             30%                -                   -
              Propylene glycol                      0%              17%             25%             33%                -                   -
                    Methanol                            0%               6%              12%             16%             24%         30%