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70
AST 14 C 255/00
Collector heat transfer function
This function prevents solar collectors from remaining in a stagnation state for a
long time, which would expose them to high risk of thermal stress, when solar water
heater temperature is reached. For this reason solar pump PS is reactivated
according to the following logic:
Tscs > (P22 - 10°C)
and
Tsvs < 95°C
and stopped when one of the following conditions occurs:
Tscs < (P22 -12°C)
or
Tsvs
≥
95°C
Besides, the function is disabled with Tscs > P22 and re-activated with Tscs < P22
minus 5°C.
Warning: said function is active only if either the DHW + CH, or the CH ONLY or
DHW ONLY mode is selected in the boiler, whereas it is not active in case of solar
valve probe SVS fault.
Water heater cooling function
This function consists in cooling water heater down to the set-point value by
transferring excess heat from the boiler to the solar collector. This occurs only if the
solar water heater exceeds the set-point temperature following the activation of the
"heat transfer” function.
If the remote control is not connected, the "water heater cooling” function is always
enabled, otherwise it is enabled only from 00.00 to 6.00.
Solar pump (PSOL) enabling condition for water heater cooling:
Tsvs > P19 + 2°C
and
Tscs < Tsbs -
∆
T ON (P20)
The function stops when the PSOL is switched off at the following conditions:
Tsvs < P19
or
Tscs > Tsvs -
∆
T OFF (P21)
Warning: said function is active only if either the DHW + CH, or the CH ONLY or
DHW ONLY mode is selected in the boiler, whereas it is not active in case of solar
valve probe SVS fault.
To enable the function, it is moreover necessary to set parameter P26 to 1.
Solar collector anti-freeze function
The function is enabled by setting parameter P24 to 1. In this way, when the
temperature read by the collector probe is lower than 4°C, the solar pump PSOL is
activated until the temperature reaches 5°C.
