Mikrofill Ethos RS 350, Техническая документация инструкция

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INSTALLATION
OPERATING INSTRUCTIONS
22 TECHNICAL DOCUMENTATION
WATER HARDNESS
Water hardness levels are caused by dissolved minerals in the water and will vary geographically. The harder
the water, the more likely that problems with precipitation (limescale deposits) will occur, causing permanent
damage to the boiler and associated equipment. This is a system fault and is not covered by warranty.
The water hardness is generally expressed in terms of ‘ppm’ (parts per million) and is sub-divided as follows;
• Very Soft: < 50 ppm
• Soft: 50 - 160 ppm
• Moderately Hard: 160 - 250 ppm
• Hard and Very Hard: > 250 ppm
The system should contain soft to moderately hard water, with a water hardness that does not exceed 250
ppm at a flow temperature of 80°C and ΔT 20°K. Before supplying water, the hardness and chloride value of
the system water should always be determined.
The chloride value should never exceed 200mg/litre.
If the chloride value does exceed this value, the cause should be determined. Compare the chloride value
of the supply water and the central heating system water. If this content is much higher, and if no materials
containing chloride have been added, this indicates evaporation. If the chloride content is very high, the
water is rendered more aggressive (this can be caused by, amongst other things, improperly regenerated
water softener). The system should be flushed clean and filled with low chloride water.
In order to counter unnecessary wear and tear and blockages due to impurities present in the system, we
recommend the use of a filter system with a mesh size of 100 microns. Always place this in the return line of the
secondary part of the system. In order to guarantee a properly working system and long life, one should
remove suspended and corrosive particles by installing a suitable filter.
Periodic inspection, including analysis of the system water and cleaning of the filters, should be performed.
OPERATION
The fan, which is modulated by the temperature controller, supplies the combustion air. Due to the resultant
under pressure in the venturi, the zero pressure controller in the gas valve mixes in the required quantity of gas.
Gas and air are completely mixed in the venturi, and the gas-air mixture is then fired directly into the burner.
The fan also removes the combustion gases. The boiler has no lower limit to the return water temperature. If
the temperature is low, condensate will be formed, which is removed via the discharge system.
CONTROLS
Depending on the heat requirement of the system, the boiler output will automatically modulate between
10% and 100% (10:1 turn down ratio). Below 10% load, the boiler operates on / off, based on temperature.