iWorx® SMZ1
14
505-048-2, Effective: March 10, 2015
© 2015 Taco Electronic Solutions, Inc.
Slab 2 Temperature (ST2)
This input uses a Precon III thermistor in the slab. To connect a thermistor, attach one wire to the ST2 (T14) input and
the other the adjacent COM (T15).
Snow Melt Sensor 3 (SMS3)
This input uses a snowmelt sensor (individual zone snowmelt mode set as “Zone Sense” or “Zone Sense With Idle”). To
connect the snowmelt sensor, attach one wire to the SMS3 (T13) and the other to the associated COM (T12).
Slab 3 Temperature (ST3)
This input uses a Precon III thermistor in the slab. To connect a thermistor, attach one wire to the ST3 (T11) input and
the other the adjacent COM (T12).
Snow Melt Sensor 4 (SMS4)
This input uses a snowmelt sensor (individual zone snowmelt mode set as “Zone Sense” or “Zone Sense With Idle”). To
connect the snowmelt sensor, attach one wire to the SMS4 (T10) and the other to the associated COM (T9).
Slab 4 Temperature (ST4)
This input uses a Precon III thermistor in the slab. To connect a thermistor, attach one wire to the ST4 (T8) input and
the other the adjacent COM (T9).
Global Snow Melt (SMLT)
To connect a snow melt sensor to the digital input, attach one wire of the contact to SMLT (T5) and the other wire to the
adjacent COM (T6). This must be a dry contact, normally open switch.
SMLT Heater Temp (SHT)
This input is used to read the temperature of the heating element in a five-wire SMLT sensor. Connect the yellow wire
from the sensor to SHT (T3). The sensor's black ground wire should already be connected to COM.
Outdoor Air Temperature (OAT)
This input uses a Precon III thermistor. To connect a thermistor, attach one wire to the OAT (T7) input and the other the
adjacent COM (T6). Once connected, remove the controller’s cover and move the jumper W15 from
Stat
to
UI11
.
Remember to place the UI11 dip switch in the thermistor positions (Right / Left [from the bottom]). If no ASM2 is present
on the network, the OAT sensor connected to the SMZ1 is used.
Connecting Output Devices
Zone 1 Modulating Output (Z1M)
The modulated Zone 1 output is set to 0-10 V max through the control logic. Connect the positive wire from the valve or
circulator control input to Z1M (T37) and the other wire to COM (T36).
Zone 2 Modulating Output (Z2M)
The modulated Zone 2 output is set to 0-10 V max through the control logic. Connect the positive wire from the valve or
circulator control input to Z2M (T35) and the other wire to COM (T36).
Zone 3 Modulating Output (Z3M)
The modulated Zone 3 output is set to 0-10 V max through the control logic. Connect the positive wire from the valve or
circulator control input to Z3M (T34) and the other wire to COM (T33).
Zone 4 Modulating Output (Z4M)
The modulated Zone 4 output is set to 0-10 V max through the control logic. Connect the positive wire from the valve or
circulator control input to Z4M (T32) and the other wire to COM (T33).
Primary Circulator (PC)
The Primary Circulator output must be connected to a 24 VAC pilot relay if the load is greater than 1 Amp. See preced-
ing figures for details. If the load is less than 1 Amp, connect it to PC (T29) and TC12 (T30).
