Lochinvar HERALD HCB116CE, Installation Manual

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21.0 VIEWABLE AND CHANGEABLE CONTROL PARAMETERS
Before changing p a r a m e t e rs , n o t e t h e settings so that the unit can be returned to its
original operating parameters.
21.1 GENERAL
21.1.1 V
ACATION
M
ODE
This parameter forces the Space Heating (SH) and DHW set points to decrease by the amounts programmed in the
Night Setback Offset parameters. It is used to save energy, such as when the building is unoccupied for an extended
period of time. For this function to work, the Space Heating Night Setback Offset and/or DHW Night Setback Offset
parameters must be set to a value higher than 0°. The default value of this parameter is OFF.
21.1.2 T
IME AND
D
ATE
The control uses an internal clock for the night setback feature and for logging of events. For these features to work
correctly, the clock must be set when the boiler is first installed or anytime the boiler has been powered off for more
than four (4) hours. This parameter must be accessed to set the clock.
The internal clock does not adjust for british summer time and therefore, will require a manual
adjustment. The clock is automatically updated whenever a pc is connected and the win_pro
installer program is started.
21.1.3 S
OFTWARE
V
ERSION
The software version allows the user to view the software version in use by the control. This software controls the
operation of the boiler. When a new software version becomes available, the existing control can be replaced with a
new control to update the software.
Software version is read only.
21.1.4 T
EMPERATURE UNITS
(°C / °F)
The control can be configured to display temperature in either °C or °F. This parameter can be changed by the user
or the installer by accessing the Temperature Units parameter. The default is °F.
21.1.5 S
PACE
H
EATING
(SH)
AND
D
OMESTIC
H
OT
W
ATER
(DHW) N
IGHT
S
ETBACK
O
FFSET
Once the unit’s internal clock has been set correctly, the Night Setback feature can be used to program a lower set
point during unoccupied times. Both the space heating and DHW can be programmed for night setback. When in night
setback, the control reduces the set point by a fixed amount. For space heating, it subtracts the space heating night
setback offset from each of the SH user set points (SH1, 2, and 3 Set point parameters), or the calculated outdoor reset
set point (if lower). For DHW, it subtracts the DHW night setback offset from the tank set point (Tank Set point
parameter).
The DHW night setback will not work without a tank sensor installed.
The installer may adjust the space heating night setback offset by accessing the SH Night Setback Offset parameter
and the DHW night setback offset by accessing the DHW Night Setback Offset parameter. The minimum setting is 0°C
and the maximum setting is 50°C.