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Viega Hydronic Mixing Block User Guide
UG-HC 566234 0720 Hydronic Mixing Block
Connecting a Thermostat
Two-Wire with Battery Thermostat
Wiring schematic for part numbers 15116,
15117, and 15118.
1
Connect RC terminal on thermostat to
terminal 1 on the Hydronic Mixing Block.
2
Connect W terminal on thermostat to terminal
2 on the Hydronic Mixing Block (part number
15118 W terminal is labeled W/E).
Thermostat batteries must be installed
and working for this configuration.
Legend: Thermostat
Low Voltage
Line Voltage
Hydronic Mixing Block
Terminal 1 & 2
3)
3$
$
:
$
0
#
8
1
2
Three Wire Thermostat
Wiring schematic for part numbers 15116,
15117, and 15118.
1
Connect R from the transformer to the RC
terminal on the thermostat.
2
Connect the C from the transformer to the C
terminal on the thermostat.
3
Connect the W terminal on thermostat to
terminal 1 on the Hydronic Mixing Block (part
number 15118 W terminal is labeled W/E).
4
Connect terminal 2 from the Hydronic Mixing
Block to the C terminal on the thermostat/
transformer.
$
3
/
-
3)
3$
$
:
$
0
#
8
1
2
120 V AC
Power Supply
Class II
Transformer
Hydronic Mixing Block
Terminal 1 & 2