Adisa ADI LT 105, Техническое руководство по установке и обслуживанию

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ADI LT boiler – Technical manual Page
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15.5 DRAINING OF THE BOILER CONDENSED PRODUCTS
15.5.1. Water condensing
Having the heat exchanger in stainless steel, the ADI LT boiler has no limit of the minimum return temperature.
This allows obtaining a higher profit of the heat generated by the combustion products:
- Sensible heat: the heat transferred due to the cooling of burnt gases.
- Latent heat: the heat transferred due to the energy issuing from the water steam when it condenses
and turns into liquid.
The energetic efficiency added thanks to the use of the latent heat of the condensed products can be up to 11%
in case of natural gas, which is the relation between the High Calorific Value (HCV) and the Low Calorific Value
(LCV).
The theoretical volume of the condensed products can be:
- 1,63 kg / m3
- up to 0,14 kg / kWh
15.5.2. Neutralization treatment of the condensed products.
For natural gas, the condensed water has a pH value that can be between 3,5 and 5,5.
It is recommended to realize a neutralization treatment of the condensed products before throwing them to the
general drainage of the building, or similar.
Generally, you have to make the condensed products circulate mixed with a sort of powder, which can be
calcium carbonate, hydrolyte of magnesium (salt formed by calcium hydride, CaH2, and magnesium) or similar,
in order to neutralize them, which means to increase the value of its pH so that it will be between 6,5 and 9.
It is recommended to realize periodical measurements of the water pH after the neutralization treatment: when
the value measured is lower than 6,5 it is recommended to replenish with the powder.
In any case, the neutralization treatment must be realized in conformity with the local, autonomic and national
laws.
The neutralization system should be placed at a level of height lower than the boiler draining/outlet of the
condensed products. If this is not possible, consider the installation of a pump of condensed products.
15.5.3. Evacuation piping of condensed products.
- The boiler outlet of the condensed products should be connected to a siphon.
(Fill the siphon with clean water before starting the boiler).
- Some boiler models should be placed on a base with sufficient height to allow the installation of the draining of
the condensed products, of the siphon and of the connection to the neutralization piping of the condensed
products.
- The evacuation of the condensed products to the general drainage should be realized in a visible way, through
a visible connection, open funnel or similar.
- Due to the characteristics of the condensed water, the material of the piping must be resistant to the action of
the acid water, for example: plastics (P.V.C).
- The evacuation pipe must have a minimum slope of 30 mm / metre
- Drainage by means of an external piping is not recommended, due to the risks of condensation and corrosion.
15.5.4. Boiler chimney
The chimney must be realized with materials that are resistant to condensed water, which is acid.
The gaskets joining the components of the chimney must be watertight.
The chimney must comply with the national and European regulations.