II.g) UHW pump
Activation of UHW pump (by selecting TURN ON) makes the
controller switch to boiler priority mode. In this mode, the
boiler pump ( UHW) is activated until the set temperature is
reached. Then, the pump is turned off and the CH circulating
pump is activated.
The temperature of the UHW pump is adjusted by pressing (for
a few seconds) the EXIT button. The LCD will display the set
temperature and the boiler temperature. To activate the UHW
pump, the set temperature must be above the pump activation
threshold (see page 6 II d). The range of the set temperature is
adjusted by means of and . After a few seconds, the display is
restored. Upon reaching the set temperature, the UHW pump
is deactivated and the CH pump starts.
In this mode, the operation of the fan is limited to 62°C at the
boiler to prevent boiler overheating. This condition continuous
until the boiler set temperature is reached. Upon reaching the
temperature, the UHW pump is deactivated and the CH pump
starts. The CH pump continuous to operate until the boiler
temperature drops below the set value. Then, the CH pump is
turned off and the UHW pump is started. UHW priority means
that the utility hot water is heated first and the water in
radiators is heated afterwards.
WARNING: The boiler should be fitted with non-return valves in
the CH and UHW circulation systems. The valve on the UHW
pump prevents discharge of hot water from the boiler. The
valve on CH pump prevents hot water from entering the house.
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