Dhw Settings - Lochinvar HERALD HCB46CE Installation Manual

21.5

DHW SETTINGS

21.5.1 DHW T S P
ANK ET OINT
By installing a tank sensor, the SMART SYSTEM control can perform the tank thermostat function. The SMART
SYSTEM control automatically detects the presence of this sensor, and generates a DHW call for heat when the tank
temperature drops below the tank set point differential (Tank Set point Differential parameter), and finishes the call
for heat when the tank temperature reaches tank set point. This parameter can be changed by the installer by accessing
the DHW Tank Set point parameter. The temperature range of this parameter is from the tank minimum set point to the
tank maximum set point. The default value is 49°C.
When the tank sensor is connected the boiler will still fire during a DHW demand even if the Herald is turned off via the
BMS connections.
21.5.2 T S P D
ANK ET OINT IFFERENTIAL
When a tank sensor is installed, the tank temperature must drop this amount below the tank set point (DHW Tank Set
point parameter) before the boiler turns back on. The installer can adjust this setting by accessing the Tank Set point
Differential parameter. The minimum setting is 0°C, and the maximum is 22°C. The default setting is 3°C.
21.5.3 DHW B S P
OILER ET
When a DHW call for heat becomes active, the control will use the DHW boiler set point to determine the firing rate of
the boiler based on the boiler outlet water temperature, or system temperature when DHW is programmed as a
zone. This parameter can be changed by the installer by accessing the DHW Boiler Set point parameter. The
temperature range of this parameter is 20°C to 88°C. The default value is 82°C.
21.5.4 DHW B O
OILER FFSET
This parameter reflects the degrees above DHW boiler set point the temperature has to go before the boiler will shut
off. The range is 0°C to 11°C. The default setting is 2.8°C.
21.5.5 DHW B D
OILER IFFERENTIAL
This parameter reflects the degrees below DHW boiler offset set point the temperature has to go before the boiler
turns back on. The range is 0°C to 33°C. The default setting is 6°C.
21.5.6 DHW R
ECIRCULATION
The SMART SYSTEM control will turn the DHW recirculation pump on when the DHW return water temperature drops
below the DHW Tank Set Point minus the DHW Recirculation Pump Offset. The range for this parameter is 0° to
30°C. The default value is 5°C.
21.5.7 DHW R
ECIRCULATION
Once the SMART SYSTEM control turns the DHW recirculation pump on, the DHW return water temperature must
increase by the DHW Recirculation Pump Differential before the control turns the DHW recirculation pump back off.
The range of this parameter is 0° to 50°C. The default value is 2°C.
21.5.8 T M S
ANK INIMUM ET
This setting controls the minimum tank set point for the tank temperature. The installer can adjust this by accessing
the Tank Minimum Set point parameter. The minimum setting is 16°C and the maximum setting is the maximum tank
set point (Tank Maximum Set point parameter). The default value is 16°C.
21.5.9 T M S
ANK AXIMUM ET
This setting controls the maximum tank set point for the tank temperature. The installer can adjust this by accessing
the Tank Maximum Set point parameter. The minimum setting is the minimum tank set point (Tank Minimum Set
point parameter) and the maximum setting is 88°C. The default value is 88°C.
OINT
P O (R P
UMP FFSET ECIRCULATION
P D
UMP IFFERENTIAL
P
OINT
P
OINT
)
UMP
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