Installation
70
EN
2.10.1 Water quality requirements
Water is used as a heat transfer fluid within the heating/co-
oling system.
The quality of the water utilized must be compliant with the
requirements indicated in the UNI 8065 standard, otherwise
an appropriate treatment system must be installed.
Reference values
PH
6-8
Electrical conductivity
less than 200 mV/cm (25°C)
Chlorine ions
less than 50 ppm
Sulphuric acid ions
less than 50 ppm
Total iron
less than 0.3 ppm
M Alkalinity
less than 50 ppm
Total hardness
less than 25 °F
Sulphur ions
none
Ammonium ions
none
Silicon ions
less than 30 ppm
If the hardness of the initial water exceeds the value indica-
ted in the table, a water softening system must be utilized.
Excessive water softening (total hardness <15 °F) could re-
sult corrosion phenomena wherever contact is made with
metallic elements (pipes or boiler components). The con-
ductivity value must also be kept within 200 µS/cm.
2.10 CHARGING AND EMPTYING THE SYSTEMS
RIELLO NXC units requires a charging system.
Before filling or emptying the system, set the system's main
switch and the device's main switch to their "0" (off) posi-
tions.
2.10.2 Charging the system
• Prior to initiating the filling operation, check that the di-
scharge valve is closed;
• check that the system's air vents are open;
• open the water system's shut-off devices;
• slowly charge the system;
• close the system's air vents as soon as water starts to come
out.
1
1
NXC 017-021
1. Filling unit
1
1
ON
OFF
ON
OFF
NXC 026-040
NXH 026-040
