Taco Electronic Solutions iWorx ZXU1, Installation Manual

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iWorx® ZXU1
502-007, Effective: May 30, 2013 17
© 2013 Taco Electronic Solutions, Inc.
ZXU1 Snowmelt Radiant Zone Mixing
Secondary Temperature Mixing Control
Application for snowmelt:
• Radiant Infloor, snowmelt, chilled beam or any sec-
ondary water temperature required versus main sup-
ply water temperature.
Sensors Required: Supply Water Temp, Return Water
Temp, Outside Air Temp, Snowmelt Sensor and Sensor
Socket
NOTE: Snowmelt example shown is for a
mixed hot water snowmelt application. Chilled
water applications may require additional sen-
sors such as Humidity Sensors, Room Temp or
Slab Temperature Sensors. Refer to
ZXU1
Application Guide #505-007.
Setup Instructions
1.Complete steps 1-22 detailed above.
2.Press
SMLT Settings .
3.The SMLT Settings menu opens.
a.Specify Cutoff Temp in degrees. Indicates the min-
imum Outside Air Temp at which snowmelting can
occur.
b.Specify maxDifferential in Degrees. This value is
the maximum temperature difference between
Boiler Supply and Boiler Return Temperature.
c. Override is used for system commissioning or to
force the system on.
d.Press Save .
4.Press Next 13 .
5.Press Setpoint Mode .
6.The Setpoint Mode menu opens.
a.Select “Snowmelt Differential.” If the difference
between Supply and Return Temperature is greater
than the Max Differential in the Snowmelt Settings,
the Effective Setpoint gets clamped to the Supply
Temperature.
b.Or select “Snowmelt.” Snowmelt Setpoint is calcu-
lated exactly like the Reset Setpoint.
c. Press Save .