Viessmann Vitocrossal 300 CU3A Application Manual page 48

Vitocrossal CU3A
Zone Control Wizard—3 ZC—ZC1 Setpoint Demand with ZC2 Weather Compensated
This application shows 3 heating circuits, where a combination of pumps, zone valves and two types of call for heat
are utilized. The ZC1 demand input comes from a Multizone Control which is responsible for accepting thermostat
calls where a respective pump is enabled. The ZC1 is also configured for a Weather Compensated function which
allows a zone set point to be calculated based on the slope and shift settings. The ZC2 input from the second
Mutlizone Control is configured for a Fixed Setpoint when there is a call. This Mutlizone Control is responsible for
controlling 2 zone valves based on the 2 thermostats. Lastly, ZC3 input comes from a snow melt control. The ZC3
is also configured to provide pump control on the 157 plug output.
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Select the correct number of Zone Circuit connections
with respect to the number of controls connected
to the DE connections. Press OK
This application is based on a Weather Compensated
for ZC1. Arrow down and press OK to confirm setting.
The Slope and Shift settings can be adjusted to allow a heating curve
to be set. When there is a zone heat demand, the calculated set point
will be used as long as the demand is present. Arrow up or down to
move to the shift setting from slope. Making an adjustment of either
setting will graphically indicate how the heating curve moves.
Once the settings have been made, press OK to con-
tinue. These settings can be easily adjusted later on
should they need to be changed.
There is no pump associated with ZC1 for this
particular application. OK continues to the ZC2 circuit.
The Zone Circuit 2 is to be set for Fixed Setpoint
temperature demand. Press OK to select and continue.
The next screen allows for a set point adjustment of
the zone target temperature
The Zone Circuit 3 as shown below is to be set for
Fixed Setpoint temperature demand. Press OK to
select and continue. The next screen allows for a set
point adjustment of the zone target temperature and
lastly the selection of the 157 pump output.