Viega Hydronic Mixing Block User manual
User Guide
Viega Hydronic Mixing Block
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Viega products are designed to be
installed by licensed and trained
plumbing, mechanical, and electrical
professionals who are familiar with Viega
products and their installation.
Installation by non-professionals may
void Viega LLC’s warranty.
This document is subject to updates.
For the most current Viega technical
literature please visit www.viega.us.
The Hydronic Mixing Block is a mixing device
and boiler control with a built in circulator and
system controller. The block can provide either
a xed or reset water temperature via start/
stop or constant uid circulation. The following
pages outline step-by-step instructions for the
installation, piping/wiring, and programming of
the Hydronic Mixing Block.
CAUTION!
Only suitably qualified individuals with
formal training in electrical and HVAC
controls should attempt the installation of this
equipment. Incorrect wiring and installation
will affect the warranty provided with this unit.
Wiring must be completed in accordance with
the codes and practices applicable to the
jurisdiction for the actual installation.
CAUTION!
The Hydronic Mixing Block is a
microprocessor based controller and
as such is not to be regarded as a safety
(limit) control. Please consult and install the
heating or cooling appliance in accordance
with the manufacturer’s recommendations.
Wiring Terminal Block
Delivery Fitting (3)
¾" Solder
Connection*
Return Fitting (2)
Fitting Clip
Supply Fitting (1)
Backplate
Display Screen
Adjustment Buttons
Pressure/Temperature Sensor
¾" Solder
Connection*
Part No 56160
*Viega tailpieces may be used in place of solder connections.
Viega tailpieces are available for sale separately. See “Viega
Tailpieces for Use with Hydronic Mixing Block” on page 3
for options.
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Installation
1 Assemble the Hydronic Mixing Block fittings.
2 Insert fitting labeled fitting 1 into port labeled
port 1 on the lower right of the Hydronic
Mixing Block. Firmly twist and press the fitting
until fully seated.
3 Once a Hydronic Mixing Block fitting is fully
seated, slide the fitting clip into the groove in
the port, securing the fitting to the block.
4 Insert fitting labeled fitting 2 into port 2 on the
lower left of the Hydronic Mixing Block. Firmly
twist and press the fitting until fully seated.
Repeat step 3 to install fitting clip for fitting 2.
5 Insert fitting labeled fitting 3 into port labeled
port 3 on the upper left. Firmly twist and
press the fitting until fully seated. Repeat step
3 to install fitting clip for fitting 3.
6 Attach the backplate to the wall using the four
screw mounting holes. Level the backplate.
A. Hydronic Mixing Block mounting holes
B. Backplate mounting holes
7 Slide the Hydronic Mixing Block into the
backplate. The backplate will slide into the
grooves in the Supply Fitting (fitting 1), Return
Fitting (fitting 2), and Delivery Fitting (fitting 3).
8 Once the Hydronic Mixing Block has been
fully inserted into the backplate, secure it to
the wall using the two screws provided. The
backplate has two mounting points, one on
each side of the block.
Water can be used as a lubricant on
the fitting o-rings and the pressure/
temperature sensor o-ring.
The backplate should be secured
to a solid backing surface such as
plywood or directly through drywall
into wall studs. Drywall anchors or hollow wall
anchors should not be used. Use flat head
screws or #6 or smaller pan head screws for
mounting the backplate. If mounting directly
into wood backing, use 1" screws. If mounting
through sheet rock, use 1½" screws (screws
not included).
*This port is plugged internally and will
not be used.
1
2
3
1 2
1
3
1
5
3
6
A
A
B
7
1
4
2
*
8
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9 Insert the wiring terminal block into the
left side of the display screen. Firmly push
inwards until fully seated.
10 To install the pressure/temperature sensor into
the Delivery Fitting (3), firmly push down until
seated and secure with the stainless steel
sensor clip. Install clip with the lip facing down.
Connecting the Hydronic Mixing
Block to the Primary Loop
1 Connect the Supply Fitting (fitting 1) on the
Hydronic Mixing Block to the supply tee on
the primary loop.
2
Connect the Return Fitting (fitting 2) to the return
piping from the manifold. The branch connection
on the Return Fitting (fitting 2) should connect to
the return tee on the primary loop.
3 Connect the Delivery Fitting (fitting 3) to the
supply piping to the manifold.
Step 2
Step 3
Step 1
Direction of ow
Part No. Dimension
(in)
Connection
79800 ½ x 1 ProPress x F BSP
79805 ¾ x 1 ProPress x F BSP
79810 1 x 1 ProPress x F BSP
96140 ¾ x 1 PureFlow x F BSP
96160 1 x 1 PureFlow x F BSP
Viega Tailpieces for Use with
Hydronic Mixing Block
The following tailpieces may be used when
connecting piping to the Hydronic Mixing
Block. They are sold separately.
Make sure to disassemble the fittings
before soldering. The solder cup
should not be attached to the gasket
or Hydronic Mixing Block when soldering.
Allow soldered fittings to cool to room
temperature before re-assembly.
910
3
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Wiring
Connecting to the Wiring
Terminal Block
All wiring shall be done through the wiring
terminal block. The wiring terminal block has 9
terminals and should be connected as follows:
■ Terminal 1,2 - Thermostat or end switch
(terminal 1 and 2 can accept a dry contact or
24v powered contact).
■ Terminal 3,4 - Outdoor Sensor.
■ Terminal 4,5 - Boiler Sensor.
■ Terminal 6,7 - Boiler Contact (TT) relay rated
for 24V AC 1.0 Max AMPS.
■ Terminal 8,9 - Internal relay rated for 24V AC
1.0 Max Amps. With the addition of a pump
and boiler relay this contact can be used for
low head primary loop pump control.
Plug cord into 120V AC - standard wall outlet
(altering the cord will void the warranty).
End Switch from Zone
Control or Thermostat
(Dry or Powered contact)
Pump
and
Boiler
Relay
120 VAC
Power
Supply
Primary Loop
Pump P1
24
VAC
Com
Boiler Sensor
S1
Boiler
Hydronic Mixing Block
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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
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$$38 /5$ "#
1
2
$
3
/
-
Terminal 1 & 2
120 V AC
Power Supply
Class II
Transformer
Three Wire Thermostat
Wiring schematic for part number 18050:
1 Connect R from the transformer to the R
terminal on the thermostat.
2 Connect C from the transformer to C terminal
on the thermostat.
3 Connect W terminal on the thermostat to
terminal 1 on the Hydronic Mixing Block.
4 Connect C terminal on the thermostat to
terminal 2 on the Hydronic Mixing Block.
Legend: Thermostat
Low Voltage
Line Voltage
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Connect the Wiring
1 Connect 18 AWG or similar wire to the two
terminals provided in the enclosure and run the
wires from the Outdoor Sensor to terminal 3
and 4 on the wiring terminal block. Do not run
the wires parallel to telephone or power cables.
If the sensor wires are located in an area with
strong sources of electromagnetic interference
(EMI), shielded cable or twisted pair should be
used or the wires can be run in a grounded
metal conduit. If using shielded cable, the shield
wire should be connected to the Com terminal
(terminal 4) on the Hydronic Mixing Block and
not to earth ground.
2 Replace the front cover of the sensor enclosure.
Sensor Wiring
Installing the Outdoor Sensor
The Viega Hydronic Mixing Block includes an Outdoor
Sensor which provides an accurate measurement
of the outdoor temperature. The Outdoor Sensor
is protected by a white, UV-resistant, ABS plastic
enclosure and contains a 10 kΩ thermistor.
Mounting the Sensor
The temperature sensor (
10 kΩ
thermistor) is built into the Outdoor
Sensor enclosure.
1 Remove the screw and pull the front cover off
the sensor enclosure.
2 Mount the Outdoor Sensor to a wall, with
the wiring entering either through the back or
bottom of the enclosure. Do not mount the
Outdoor Sensor with the conduit knockout
facing upwards as rain could enter the
enclosure and damage the sensor.
3 The Outdoor Sensor should be mounted on a
wall which best represents the heat load on the
building (a northern wall for most buildings and
a southern facing wall for buildings with large
south facing glass areas). The Outdoor Sensor
should not be exposed to heat sources such as
ventilation or window openings.
4 The Outdoor Sensor should be installed at an
elevation above the ground that will prevent
accidental damage, tampering, or snow/ice
build up.
Sensor with Rear Entry Wiring
Sensor with Bottom Entry Wiring
Maximum wire length from control to
sensor is 500 ft.
If used in AQUASTAT mode, the Boiler
Sensor can be placed on the supply
or the return. RESET or CONDENSING
boiler modes require the Boiler Sensor to be
installed on the supply.
When extending sensor wires, use
18 gauge wire and do not extend
over 500 feet.
Installing the Boiler Sensor
1 Attach wires to terminal 4, 5
on wiring terminal block.
2 Run the sensor back to the supply
side of the primary loop. Attach to
the supply piping before the closely
spaced tees with the included zip
tie. Cover the sensor with insulation
for accurate reading.
Wiring
connection
for Outdoor
Sensor wires
(terminal 3 and 4)
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Piping
■ This drawing shows system piping
concept only. Installer is responsible
for all equipment and detailing
required by local codes.
■ Size header piping for maximum ow
velocity of 2 ft./sec.
■ All other piping should be sized for a
maximum ow velocity of 4 ft./sec.
■ Install a minimum of 12 diameters
of straight pipe upstream of all
circulators and check valves.
■ Install isolating anges or isolating
valves on all circulators.
■ Install purging valve(s) on all circuits.
■ All closely spaced tees shall be
within 4 pipe diameter center-to-
center spacing.
■ Install minimum of 6 pipe diameters
of straight pipe upstream and
downstream of all closely spaced tees.
■ Dierential pressure bypass valve
prevents ow noise under partial
load conditions (some zone valves
closed).
■ Set dierential pressure bypass
valve to delta P of distribution
system with all zones open + 1 psi
■ Not all components may be required
depending on control strategy (i.e.
constant circulation).
Legend: 4-Way Mixing Valve and Motor
Hydronic Mixing Block Pressure Dierential Bypass Valve
Spring check Stainless Manifold with Flow Gauges
Circulator Baseboard Zone(s)
Draw O (Purge Valve) Diaphragm-Type Expansion Tank
Make-up Water Zone Valve
Conceptual Piping Diagram
Zone
Control
Outdoor
Sensor (S3)
Boiler
Sensor (S1)
Primary Loop Pump (P1)
Boiler Relay
P2
1 Stage
T-Stat
1 Stage
T-Stat 1 Stage
T-Stat
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Conceptual Electrical Schematic
Wiring
■ This drawing shows system wiring concept
only. Installer is responsible for all equipment
and detailing required by local codes.
■ All wiring shall be in conformance with the
latest edition of the National Electrical Code.
■ Maximum current rating of the Hydronic
Mixing Block is 1 AMP.
■ Consult with control / boiler manufacturer for
limitations and installation instructions.
■ Do not run the wires parallel to telephone
or power cables. If the sensor wires are
located in an area with strong sources of
electromagnetic interference (EMI), shielded
cable or twisted pair should be used or the
wires can be run in a grounded metal conduit.
If using shielded cable, the shield wire should
be connected to the Com terminal (terminal 4)
on the control and not to earth ground. Use
18 AWG copper wiring for all sensor wiring.
Sensors should be located before the closely
spaced tees.
Legend: Basic Heating Control
Sensors P1 = Primary Loop Circulator
Low Voltage S1 = Boiler Sensor
Line Voltage S3 = Outside Sensor
End Switch from Zone Control or
Thermostat (Dry or Powered Contact)
Outdoor
Sensor (S3)
Pump and
Boiler Relay
120 V AC
Power Supply
Primary Loop
Pump (P1)
Boiler
Sensor (S1)
Boiler
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Power On Sequence
When the Hydronic Mixing Block is plugged in,
it will go through a power on sequence:
■ The display will show the current rmware
version and then verify the valve function
by ramping up to 100% and back down to
0%. Please note the rmware version here:
__________.
■ After the Valve Check is complete, the
display will then cycle through the dierent
display colors in the following order:
■ Red
■ Dark Blue
■ Yellow/Green
■ Light Blue/Gray
■ Purple
■ After the display color sequence is complete,
the display will change to the Dark Blue color
and show the STATUS Screen. After another
moment, it will display the current data and
update to the color that reects the current
status. The user can navigate the menus after
the power on sequence is complete..
Programming
Setup Menu
■ The SETUP MENU is used for entering the
design values, as well as assigning dierent
control options to the circulator and boiler. To
access the SETUP MENU, push the middle
rectangular button on the STATUS
screen. Use the up and down arrow keys
to scroll through the various settings.
■ To select an item, align the cursor arrow
with the item you wish to select and press
the middle rectangular button . The arrow
will become solid, which indicates that an
item has been selected.
■ Once adjustment is complete, push the
middle rectangular button. This will de-select
the item.
■ To go to the previous screen, select BACK
and press the middle rectangular button.
■ If the SETUP MENU is left idle for more than
90 seconds, the display will change to the
STATUS screen and the Hydronic Mixing
Block will begin operating.
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This function is not available with
BOILER AQUASTAT mode.
■ OPERATION: CONSTANT — The circulator
is constantly on and will only be shut o with
warm weather shut down (WWSD). Usually
used with RESET mode.
Circulator Settings
■ OPERATION: ON/OFF — The circulator is
turned on/o as demand requires. Default is
set to ON/OFF.
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Design Temperature Settings
■ OUT DESIGN — Outdoor temperature used
to calculate heat loss. This temperature is
based on location and can be obtained from
outdoor design charts.
Range: -40°F to 70°F
Default: 10°F
■ ROOM DESIGN — Desired room temperature
used in heat loss calculation.
Range: 35°F to 120°F
Default: 70°F
■ WWSD — Temperature at which the building
does not need heat and the control will no
longer activate the circulator.
Range: 35°F to 120°F
Default: 70°F
■ TEMP CONTROL: FIXED — The control
will maintain a constant (FIXED) water
temperature.
■ WATER TEMP — The xed water
temperature.
Range: 50°F to 180°F
Default: 120°F
■ TEMP CONTROL: RESET — Water
temperature will adjust based on outdoor
temperature; as the outdoor temperature
increases, the water temperature will
decrease, and vice versa. By using this type
of control strategy the output of the radiant
system will meet the load of the structure,
resulting in an energy savings for the building
owner. Default is set to: RESET.
■ MIX DESIGN — The design water
temperature specied by the radiant design.
This is the maximum water temperature that
will be supplied.
Range: 50°F to 180°F
Default: 120°F
■ MIX MIN — The minimum supply temperature
for the mixing system.
Range: 50°F to 180°F
Default: 70°F
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Boiler Settings
■ TYPE: RESET — This setting allows for the
boiler to change supply water temperature
based on outdoor temperatures. Default is
set to: RESET.
■ BOILER DESIGN — The water temperature
needed on design day.
Range: 70°F to 200°F
Default: 180°F
■ BOILER MIN — Lowest temperature the
boiler is allowed to supply. This temperature
needs to be set high enough for the
boiler to be able to maintain mixed water
temperatures.
Range: 70°F to 200°F
Default: 140°F
■ BOILER DIFF — Determines turn on and
shut o temperatures. This setting will allow
the boiler to go above the boiler target by
half of this setting. Example: if the BOILER
DIFF is set at 20°F, the boiler will run until the
temperature is 10°F above the boiler target
setting and turn on when the temperature is
10° below the boiler target temp.
Range: 10°F to 50°F
Default: 20°F
■ TYPE: AQUASTAT — Used when the boiler
is a non-condensing boiler that maintains its
own temperature settings. This mode is not
available with CONSTANT circulation mode.
■ SENSOR — Installed on either SUPPLY
or RETURN. Installation must be properly
identied in this setting.
■ SUPPLY MIN/RETURN MIN — Minimum
supply/return temperature.
Range: 70°F to 200°F
Default: 140°F
■ TYPE: CONDENSING — Used when the
boiler is a condensing boiler that maintains
its own temperature settings.
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Defaults \ Purge
■ °C OR °F — Select between CELSIUS or
FAHRENHEIT.
Default: FAHRENHEIT
■ OVERWRITE DEFAULTS — Allows the
end user to overwrite the Factory Default
Settings with the desired settings. Viega
LLC recommends performing this procedure
after selecting all of the desired settings and
noting them in the “Settings Template and
User Selections” on page 16.
■ RESTORE DEFAULTS — Restores the current
Default Settings. If the Factory Default
Settings were overwritten, the User Settings
selected during the overwrite will be restored.
■ PURGE — Selecting this feature will bring
you to PURGE MODE.
Purge Mode
■ ACTIVATE — Will open the internal valve for
30 minutes to allow for purging.
■ CANCEL — Will end the PURGE MODE, end
the timer, and close the internal valve.
Setup Menu
■ To view the STATUS screen, select BACK
with the cursor arrow in the SETUP MENU
and push the middle rectangular button.
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Status Screen
The STATUS screen shows the actual
temperatures as read by the sensors and the
target temperatures the control is trying to obtain.
■ HEATING — If the display screen is red and
heating is displayed on the upper left corner
of the STATUS screen, the control is in heating
mode and there is a boiler demand. If the display
screen is blue, it means there is a heating
demand but the boiler is o. If the screen is light
blue/gray, there is no heating demand.
■ BOIL SUP/RET — The temperature of the
boiler supply/return. This will be dictated by the
sensor location. If on the supply this will read:
BOIL SUP. If on the return it will read BOIL RET.
When the boiler sensor is bad or there is a
broken/ shorted wire, it will be represented by 5
dashes ----- in the supply eld and the display
will blink red. The control will supply 80°F to the
oor/ emitter to keep the system from freezing.
■ SYSTEM — The mixed water temperature
that the Hydronic Mixing Block supplies. This
symbol: ----- present in the eld means the
sensor is bad or the wire is broken or shorted.
■ OUTDOOR — The outdoor temperature as
read by the outdoor sensor.
■ PRESSURE — The system pressure is read
by the temperature/pressure sensor located
to the left of the display screen. The number
displayed in this eld is the system pressure.
If the words LOW are present in the pressure
eld for one minute, the control will shut o
to prevent damage. If the symbol: ----- is
present, it indicates the sensor is bad or the
wire is broken or shorted.
■ VALVE POSITION — Identies the position of
the internal valve.
■ BOILER PROTECT — If the display screen
is yellowish/green and BOILER PROTECT
is present in the lower left and right of the
screen, the boiler is in protection mode.
Screen Color Indicator Status
Light Blue/Gray No Heat Demand
Solid Red Heat demand, boiler running
Yellow/Green Heat demand, boiler running but in boiler protection mode
Dark Blue Heat demand, boiler satisfied
Blinking Red Failed boiler sensor or broken/shorted wire. Under this condition the block
will supply 80°F fluid to the floor/emitter to keep the system from freezing
Blinking Purple PURGE MODE, will open valve for 30 min duration to allow for purging
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Settings Template and User Selections
Parameter Sub-Menu Sub-Menu
Option #1
Sub-Menu
Option #2
Sub-Menu
Option #3
User
Selection
CIRCULATOR
CONTROL
OPERATION
Default: ON/OFF ON/OFF
CONSTANT
**Not available w/ Aquastat
Often used w/ RESET mode
NA
DESIGN
TEMPS
OUT DESIGN Range: -40°F to 120°F
Default: 10°F NA NA
ROOM DESIGN Range: 35°F to 120°F
Default: 70°F NA NA
WWSD Range: 35°F to 120°F
Default: 70°F NA NA
WATER TEMP
CONTROL
TEMP CONTROL
Default: RESET FIXED RESET NA
Fixed: WATER
TEMP
Range: 50°F to 180°F
Default: 120°F NA NA
Reset: MIX
DESIGN NA Range: 50°F to 180°F
Default: 120°F NA
Reset: MIX MIN NA Range: 50°F to 180°F
Default: 70°F NA
BOILER
SETTINGS
TYPE
Default: RESET RESET CONDENSING
AQUASTAT
**Not available w/
CONSTANT
BOILER DESIGN Range: 70°F to 200°F
Default: 180°F NA NA
BOILER MIN Range: 70°F to 200°F
Default: 140°F NA NA
BOILER DIFF Range: 10°F to 50°F
Default: 20°F NA NA
SENSOR
Default: SUPPLY
RESET:
SUPPLY
CONDENSING:
SUPPLY
AQUASTAT:
SUPPLY vs. RETURN
SUPPLY/RETURN
MIN NA NA Range: 70°F to 200°F
Default: 140°F
DEFAULTS/
PURGE
°C vs. °F
Default: °F NA NA NA NA
OVERWRITE
DEFAULTS NA NA NA NA
RESTORE
DEFAULTS NA NA NA NA
PURGE NA NA NA NA
BACK NA NA NA NA NA
If a power loss occurs, the Hydronic Mixing Block will return to the Factory Default Settings unless they are overwritten.
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Testing the Hydronic Mixing Block
When piping is complete, test the Hydronic
Mixing Block and system piping.
1 Ensure air vent cap is tight before testing.
2 Pressurize the system to a maximum of 100
psi for one hour.
3 Once the system maintains 100 psi for one
hour, carefully remove air pressure from the
system and fill with fluid.
Purging
When testing is complete, purge the Hydronic
Mixing Block.
1 Shut the power off to the boiler.
2 Purge with cool water only. If the boiler is hot
it should be cooled down prior to purging
in order to protect the floor coverings from
surface temperatures above 85°F.
3 Plug in the Hydronic Mixing Block. Allow it to
run through its power on sequence and bring
you to the STATUS screen.
4 From the STATUS screen, push the middle
rectangular button.
5 DEFAULTS/PURGE.
6 Select PURGE.
7 Select ACTIVATE.
■Selecting ACTIVATE will cause the screen
to turn purple, at which time the internal
valve will open. Once the valve is open,
the screen will blink purple and start a 30
minute timer to allow for purging.
■If more time is needed, ACTIVATE may be
selected as many times as necessary to
complete system purging.
■If less time is needed, purge can be
cancelled by selecting CANCEL.
8 Allow the Hydronic Mixing Block to be filled
with fluid from the supply side piping.
9 Close the valve on the return piping to the
boiler.
10 Open the purge valve to allow trapped air to
be eliminated.
11 Continue to allow fluid to run into the block
and out the purge valve until all air is removed
from the system.
12 Once purging is complete, return all valves to
normal operating position.
13 Open the air vent cap to allow air to escape
under normal operation.
14 Once the Hydronic Mixing Block, boiler,
and piping have been purged and properly
pressurized, restart the boiler.
Testing the Sensors
Outdoor Sensor / Boiler Sensor
1a Outdoor Sensor
■ Use a thermometer to read the outdoor
temperature.
1b Boiler Sensor
■ Use an infrared or digital thermometer
to read the temperature where the boiler
sensor attaches.
2 Using an ohm meter capable of measuring
10kΩ, measure the resistance present at the
sensor.
3 Using the “Sensor Resistance Chart” on page
18, compare the measured temperature/
ohm reading to what is in the chart. If reading
is off by ± 5%, the sensor is bad.
Do not apply voltage to the sensors
as this will damage them.
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Sensor Resistance Chart
Temperature Resistance Temperature Resistance
°F °C Ω °F °C Ω
-50 -46 490,813 90 32 7,334
-45 -43 405,710 95 35 6,532
-40 -40 336,606 100 38 5,828
-35 -37 280,279 105 41 5,210
-30 -34 234,196 110 43 4,665
-25 -32 196,358 115 46 4,184
-20 -29 165,180 120 49 3,760
-15 -26 139,402 125 52 3,383
-10 -23 118,018 130 54 3,050
-5 -21 100,221 135 57 2,754
0 -18 85,362 140 60 2,490
5 -15 72,918 145 63 2,255
10 -12 62,465 150 66 2,045
15 -9 53,658 155 68 1,857
20 -7 46,218 160 71 1,689
25 -4 39,913 165 74 1,538
30 -1 34,558 170 77 1,403
35 2 29,996 175 79 1,281
40 4 26,099 180 82 1,172
45 7 22,763 185 85 1,073
50 10 19,900 190 88 983
55 13 17,436 195 91 903
60 16 15,311 200 93 829
65 18 13,474 205 96 763
70 21 11,883 210 99 703
75 24 10,501 215 102 648
80 27 9,299 220 104 598
85 29 8,250 225 107 553
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Viega Hydronic Mixing Block User Guide
UG-HC 566234 0720 Hydronic Mixing Block
Viega LLC
585 Interlocken Blvd.
Broomfield, CO 80021
Phone (800) 976-9819
www.viega.us
Viega Hydronic Mixing Block User Guide
UG-HC 566234 0720 Hydronic Mixing Block
Table of contents
