The DHW loading is the same as described in “Solar Control feeds the DHW”. All the switching conditions and setting rules are the same.
The solar pump will switch on or the variable speed pump starts with its maximum speed (POW-01) if:
where
delta Ton = SOLP-01 + (20 - FilteredOATemp) * (SOLP-03 - SOLP-01)/ 35
whereas FilteredOATemp is the filtered outside air temperature
When the outdoor temperature > 20°C, delta Ton is equal to SOLP-01.
Table 7. Parameter List
Description |
Value Range |
Default Value |
Unit |
SOLP-01: temperature difference to switch on at OAT >= 20 °C |
-30 … 30 |
6 |
K |
SOLP-02: temperature difference to switch off/ over |
-30 … 30 |
3 |
K |
SOLP-03: temperature difference to switch on when the OAT = -15 °C |
-30 … 30 |
6 |
K |
PMP-03: pump minimum off time |
0…120 |
20 |
sec |