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the fuel quantity is allocated adequately to the air volume. The boiler temperature increase against
the heating branch desired temperature is 5 °C (set by the manufacturer).
b) attenuation regime – after the requirement for heat has ceased the boiler goes over to the
attenuation regime. The minimum boiler temperature is kept in the attenuation regime.
•
Boiler pump – the pump is switched on when 55 °C has been reached (set by the manufacturer).
The pump is switched off when the temperature has dropped by 5 °C against the setting by the
manufacturer. In the attenuation regime the pump is switched on at the temperature 70 °C and
switched off when the temperature has dropped by 5 °C.
•
heating branch pump – is switched on together with the requirement for heat. After the requirement
for warm water has ceased the pump will be in slowing-down regime
•
boiler antifreeze protection- it depends on the actual water temperature in the boiler. In case the
water temperature in the boiler has dropped below 5°C the boiler pump will switch on.
In order to save the regulator safety functions the boiler shouldn’t be disconnected from mains.
In case of boiler disconnection from mains time in regulator might stop and consequently the time
regimes will switch incorrectly. Then the boiler minimum temperature is not kept and in an extreme
case (boiler near an open window in winter season, boiler fault) boiler and heating circuit could
freeze up. At the switched off boiler (but not disconnected from mains) the antifreeze protection is
active by means of pumps.
In an extreme case also the fuel fire penetration into reservoir (pellets used the fuel) can occur. At the
switched off boiler (but not disconnected from mains) the protection against fuel fire penetration into
reservoir is active. In case of a long-term electricity outage pellets should be removed from the
burner in order to prevent their fire penetration to the reservoir. In this way we prevent the burning
fuel from being poured with water (which is the function of emergency fire extinguishing system –
see chap. 5.2.7) and we are spared of complicated removal of soaked pellets from the fuel feeder
Boiler (cursor is above symbol
), heating circuit (parameter P 40) or HW preparation (parameter
P 42) can be switched of by means of QAA 88 device
