Taco Radiant Mixing Block User manual

SUPERSEDES: 2FWREHU 1, 2010 EFFECTIVE: -XQH
WARNING SYMBOL: THIS SYMBOL INDICATES THE PRESENCE OF HAZARDS WHICH
CAN CAUSE SEVERE PERSONAL INJURY, SUBSTANTIAL PROPERTY DAMAGE OR
EVEN DEATH IF IGNORED.
The Taco Radiant Mixing Block
(RMB) represents a breakthrough in the design, control and installation of radiant systems. The
patentHGdesign combines a variable speed injection mixing control (RMC), injection circulator, system circulator, and air elimination
intoa single unit. Extremely versatile, the Radiant Mixing Block can be set up to operate as an outdoor reset control, a setpoint
control ora delta T limiting control.
Instruction Sheet
RMB - Radiant Mixing Block
102-151
General
MIXSUP
DEM
VIEW
F
%
1
ITEM
MENU
RADIANT MIXING BLOCK
PATENT PENDING RMB-1
TM
UL
R
CUS
Table of Contents
TYPICAL PIPING ------------------------------------------------ 2
GETTING READY ------------------------------------------------ 3
APPLICATION ---------------------------------------------------- 3
DESIGN PROCEDURE ----------------------------------------- 3
INSTALLATION OF RADIANT MIXING BLOCK -------- 4
OUTDOOR RESET MODE ------------------------------------ 5
OUTDOOR RESET SETTINGS ------------------------------ 5
SETPOINT AND DELTA T MODE --------------------------- 6
SETPOINT AND DELTA T SETTINGS --------------------- 7
BOILER OPERATION MODE --------------------------------- 7
SET UP OF RADIANT MIXING CONTROL --------------- 8
DISPLAY OPERATION ---------------------------------------- 11
TROUBLE SHOOTING ---------------------------------------- 13
ERROR MESSAGES ------------------------------------------- 14
REPLACING CARTRIDGE ASSEMBLY ------------------ 14
REPLACING THE CHECK VALVE ------------------------- 15
TECHNICAL DATA --------------------------------------------- 15
CLEANING -------------------------------------------------------- 16
LIMITED WARRANTY STATEMENT ---------------------- 16
Plant ID#: 001-3807
RADIANT MIXING BLOCK(RMB)
RADIANT MIXING CONTROL
A
Taco resource – saving product

SUPERSEDES: June 1, 2015 EFFECTIVE: July 30, 2015
U.S.Patent #7,048,200
TYPICAL PIPI G
GETTI G READY
APPLICATIO
DESIG PROCEDURE
I STALLATIO OF RADIA T MIXI G BLOCK
OUTDOOR RESET MODE
OUTDOOR RESET SETTI GS
SETPOI T A D DELTA T MODE
SETPOI T A D DELTA T SETTI GS
BOILER OPERATIO MODE
SET UP OF RADIA T MIXI G CO TROL
DISPLAY OPERATIO
TROUBLE SHOOTI G
ERROR MESSAGES
TECH ICAL DATA
CLEA I G
REPLACI G CARTRIDGE ASSEMBLY
REPLACI G THE CHECK VALVE
REPLACEME T PARTS LIST
LIMITED WARRA TY STATEME T
2
3
3
3
4
5
5
6
7
7
8
10
12
13
14
15
15
16
16
16

2
Typical Piping
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3
Design Procedure
1. Using the pump curve located below, ensure that the System Pump of the Radiant Mixing Block will provide adequate flow for the
system in which it is to be installed.
2. Using the table or equation below, determine the required flow rate for the Injection Pump.
3. Using the pump curve located below, ensure that the Injection Pump of the Radiant Mixing Block will provide adequate flow for the
system in which it is to be installed.
Application
SYSTEM PUMP CURVE INJECTION PUMP CURVE
REQUIRED INJECTION PUMP FLOW RATE
Tb = Boiler Supply Temperature
Ts = Radiant Supply Temperature
Injection Flow Rate (GPM) = BTU’s
(Tb - Ts) x 500
BTU’s x 1,000
Tb - Ts 20 40 60 80 100 120
100 0.4 0.8 1.2 1.6 2.0 2.4
80 0.5 1.0 1.5 2.0 2.5 3.0
60 0.7 1.3 2.0 2.7 3.3 4.0
40 1.0 2.0 3.0 4.0 5.0
20 2.0 4.0
Required Injection Flow Rate (GPM)
The Taco Radiant Mixing Block
 (RMB) is a complete injection mixing system. Integral to the unit is a variable speed
injectioncirculator, constant speed system circulator, air elimination, and the electronics to drive it all. With only four piping
connectionsneeded, the RMB greatly reduces the time and space required for installation. The RMB can be set up to operate as an
outdoor resetcontrol, a setpoint control or a delta T limiting control, creating flexibility never seen before in a single unit.
Ensure that the contents of this package are complete. If any of the contents are missing or damaged, please contact your local Taco
sales representative for assistance.
Contents should include the following:
• One Radiant Mixing Block, unit consists of the following parts:
•One Radiant Mixing Control
• One Green Enclosure
• One Casing with two circulators attached
• One Backplate
• One Power Cord (6 feet, attached to backplate)
•One Taco Outdoor Sensor
• Two Taco Strap-on Sensors
• One Instruction Sheet
Getting Ready
051015
FLOW (gpm)
HEAD (ft)
0
2
4
6
8
10
12
14
16
18
051015
FLOW (gpm)
HEAD (ft)
0
2
4
6
8
10
12
14
16
18

4
CAUTION:
1. The addition of petroleum based fluids or certain chemical additives to systems utilizing TACO equipment voids the
warranty.
2. Use supply wires suitable for 90°C – ATTENTION: Employer des fils d´alimentation adequats pour 90°C.
WARNING:
To avoid electrical shock, disconnect the power supply to the circulator and the main electrical unit.
WARNING:
Do not use in swimming pool or spa areas; pump has not been investigated for this application.
WARNING:
In the event the retaining screws have been pulled out of the housing, DO NOT replace them. Use of any other screw
may short out the stator windings, creating a risk of electrical shock.
Installation of the Radiant Mixing Block
STEP ONE MOUNTING
1. Mounting position – The Radiant Mixing Block must be mounted in the vertical position with the automatic air vent located at the top
of the Radiant Mixing Block.
2. To mount the Radiant Mixing Block begin by removing the Radiant Mixing Control from the front of the Radiant Mixing Block.
Remove the screwVand pull the Radiant Mixing Control straight forward. Ensure that the Radiant Mixing Control is stored in a
safeplace until it is ready to be remounted.
3.Remove the three screwVholding the green plastic cover to the Radiant Mixing Block.
4. Select a suitable location to mount the Radiant Mixing Block that allows sufficient space for easy pipe connections.
5. Attach the sheet metal base to the wall with screws (not included) through the small mounting holes. See technical data for hole
location and spacing.
6. Using four suitable screws (not included), fasten the Radiant Mixing Block to the selected location. Ensure that at least two of the
mounting screws are attached to a wall stud or similar surface.
STEP TWO PIPING CONNECTIONS
1. Using proper piping practices, connect the supply to the radiant heating system to the Radiant Supply (bottom right hand connec-
tion) as indicated on the plastic cover of the Radiant Mixing Block. Ensure that a proper isolation valve is installed.
2. Using proper piping practices, connect the return from the radiant heating system to the Radiant Return (top right hand connection)
as indicated on the plastic cover of the Radiant Mixing Block. Ensure that a proper isolation valve is installed.
3. Using proper piping practices, connect the supply from the boiler loop to the Boiler Supply (top left hand connection) as indicated
on the plastic cover of the Radiant Mixing Block. Ensure that a proper isolation valve is installed.
4. Using proper piping practices, connect the return to the boiler loop to the Boiler Return (bottom left hand connection) as indicated
on the plastic cover of the Radiant Mixing Block. Ensure that a proper isolation valve is installed.
5. Connect the Boiler Supply and Boiler Return lines to the boiler loop using standard Primary Secondary piping practices.
STEP THREE FILLING
1. Fill system with tap water – The system must be filled before operating the circulator. The bearings are water lubricated and should
not be allowed to operate dry. Filling the system will result in immediate lubrication of the bearings. It is always good practice to flush
a new system of foreign matter before starting the circulator.
2. Circulator operation – Operate the circulators for 5 minutes immediately after filling system to purge remaining air from the bearing
chamber. This is especially important when installing the circulator during the off-season.
STEP FOUR REPLACING THE FRONT COVER
1. Place the green plastic cover over the Radiant Mixing Block.
2. Using the original three screws, fasten the green plastic cover to the Radiant Mixing Block.
3. Reinstall the Radiant Mixing Control and fasten it in place with the remaining original screw. RMC wiring starts on page 9.
STEP FIVE ELECTRICAL CONNECTIONS
1. Electrical connections – Observe all applicable codes when connecting to power supply. The motors are impedance protected, and
do not require overload protection. The pumps cannot run backwards.
3. Reinstall the Radiant Mixing Control and fasten it in place with the remaining original screw. RMC wiring starts on page 8.

5
In order to properly control a hot water heating system, the amount of heat
supplied to the building must equal the amount of heat lost by the building.
The amount of heat delivered into a building depends on the temperature of
the water in the heating unit and the surface area of the heating unit. Heat-
ing units with a small surface area, such as baseboard radiators, require a
higher water temperature than heating units with a larger surface area such
as radiant floors.
The amount of heat lost from a building depends on the outdoor tempera-
ture. As the outdoor temperature becomes colder, the amount of heat a
building loses increases.
The operation of a hot water heating system can generally be improved by
adjusting the supply water temperature to the system as the outdoor tem-
perature changes. Using this approach, the heat input to the building can be
matched to the heat lost from the building. This method of controlling the
supply water temperature to a heating system greatly improves the comfort
of the system and is known as Outdoor Reset.
When a Taco Outdoor Sensor is connected to the Radiant Mixing Control (RMC), the RMC provides outdoor reset. When operating in
the outdoor reset mode of operation, the installer must set the Outdoor Design Temperature and the Design Supply Temperature in
order to establish the relationship between the outdoor temperature and the supply water temperature. This is known as setting the
Heating Curve.
SEQUENCE OF OPERATION
When the RMC receives a Demand and it is not in a WWSD, the RMC turns on the system pump and calculates a Mixing Target
temperature. The variable speed injection pump is then operated to maintain the Mixing Target temperature at the mixing supply
sensor.
The boiler contact operates as described in the Boiler Operation section. The RMC also provides boiler protection as described in the
Boiler Operation section.
DEMAND
The RMC requires a demand signal before it will begin operation. The RMC can use
either a powered or an unpowered demand signal. Once a demand signal is received, the
RMC displays the demand pointer in the display and operates as described above.
Powered Demand
The RMC recognizes a Powered Demand Signal when 24 V (ac) is applied across the
Com and Heat Dem terminals.
Unpowered Demand
The RMC recognizes an Unpowered Demand signal when a switch is closed between
the Com and Heat Dem terminals.
SYSTEM PUMP OPERATION
The RMC has an internal system pump contact. This contact turns on when the RMC has
a mixing demand and is not in a WWSD. The integrated system pump as well as an
external boiler pump may be controlled by this relay. By providing proper flow in the boiler
loop, the boiler temperature can be accurately controlled based on the mixing load.
Outdoor Reset Mode of Operation
Outdoor Reset Settings
HEATING CURVE SETTINGS
In order to establish the heating curve, the RMC must be given two points to work with. The first point is the Outdoor Reset Starting
Point and the second point is the Design Condition.
Outdoor Reset Starting Point
The Outdoor Reset Starting Point for the RMC is fixed at 72°F. This means that when the outdoor temperature is 72°F, the RMC
calculates a required supply water temperature (Mix Target) of 72°F.
Design Conditions
The design conditions represent the supply water temperature required to satisfy the heating system on the typical coldest day of
the year. These are the conditions that are used when calculating the size of the heating equipment needed to heat the building.
The Design Conditions are made up of an outdoor temperature (Outdoor Design) and a supply water temperature (Design Supply).
Com Heat
Dem
Boil Out
Powered
Demand
C
24 V (ac)
RSwitch
Com Heat
Dem
Boil Out
Unpowered
Demand
Switch

6
70 60 50 40 30 20 10 0 -10 -20
Outdoor Temperature (F)
150
140
130
120
110
100
90
80
70
60
Supply Temperature (F)
Mix Maximum
Outdoor
Design
Mix
Design
Outdoor Reset
WWSD
Starting
Point
Setpoint and Delta T Mode of Operation
In certain applications, it is desirable to maintain a fixed supply water temperature. This type of application is a setpoint application.
Examples of setpoint applications include heat pump loops, reheat coils and floor warming.
In specialized applications, such as snow melting, it is desirable to limit the rate of temperature increase in the system from the system‘s
starting temperature to its operating setpoint. This is desired in order to prevent thermal shock of the system. This type of application is
a Delta T application.
If the RMC is to operate as a setpoint control, the Outdoor Design temperature must be set to OFF and the Mixing Target temperature
must be set to the desired temperature.
If the RMC is to operate as a Delta T control, a mixing return sensor must be installed, the Outdoor Design temperature must be set to
OFF and both the Delta T Max setting and the Mixing Target temperature must be set to the desired temperature.
In both of these applications, the outdoor sensor is not to be installed
SEQUENCE OF OPERATION
When the RMC receives a Demand, the system pump is turned on.
If the Delta T Max setting is set to OFF, the variable speed injection pump is operated to maintain the mixing supply sensor at the
Mixing Target temperature set by the installer.
If the Delta T Max setting is not set to off, the variable speed injection pump is operated to maintain the mixing supply sensor at either
the Mixing Return temperature plus the Delta T Max setting or the Mixing Target temperature set by the installer whichever is lower.
The boiler contact operates as described in the Boiler Operation section. The RMC also provides boiler protection as described in the
Boiler Operation section.
DEMAND
The RMC requires a demand signal before it will begin operation. The RMC can use
either a powered or an unpowered demand signal. Once a demand signal is received, the
RMC displays the demand pointer in the display and operates as described above.
Powered Demand
The RMC recognizes a Powered Demand Signal when 24 V (ac) is applied across the
Com and Heat Dem terminals.
Outdoor Design
The Outdoor Design temperature is the average coldest day of the
year for the area in which the building is located.
Design Supply
The Design Supply temperature is the supply water temperature that
is required to heat the building when the outdoor air temperature is
as cold as the Outdoor Design temperature.
Maximum System Supply
Some systems, such as hydronic radiant floor heating, may require the
maximum supply water temperature to be limited in order to protect
certain system components from high temperatures. The RMC has a
Maximum Supply setting that can be used to limit the maximum tem-
perature that the control is allowed to use for a Mixing Target (MIX TRG)
temperature.
Minimum System Supply
Some applications, such as floor warming, may require the minimum
supply water temperature to be limited in order to provide a certain
level of occupant comfort. The RMC has a Minimum Supply setting that
can be used to limit the minimum temperature that the control is al-
lowed to use for a Mixing Target (MIX TRG) temperature. This minimum
applies as long as the RMC has a demand and is not in WWSD.
Warm Weather Shut Down (WWSD)
When the outdoor temperature is warmer than the WWSD setting, the RMC turns off the boiler and the variable speed injection
pump. If a demand is received while the RMC is in a WWSD, the RMC indicates that the demand has been received by displaying
the Demand pointer however, the MIX TRG remains as “- - -“ The RMC has a freeze protection feature that does not allow the
supply water temperature to drop below 35°F (2°C) as long as there is a mixing demand signal.
Com Heat
Dem
Boil Out
Powered
Demand
C
24 V (ac)
RSwitch

7
Outdoor Design
The Outdoor Design temperature must be set to OFF.
Mixing Target
The Mixing Target temperature is set to the desired operating temperature of the system.
Delta T Max
The Delta T Max temperature is set to the maximum temperature difference that is desired between the mixing return temperature
and the mixing supply temperature. In order to adjust this setting, a mixing return sensor must be connected to the control.
Setpoint and Delta T Settings
150
140
130
120
110
100
90
80
70
60
Supply Temperature (F)
Mix Supply = Mix Target
Setpoint
Time
Boiler Operation
The RMC operates the boiler in two basic modes of operation. The RMC can either “Control” the boiler or “Enable” the boiler. The mode
of operation is determined by the Boiler Sensor location. The boiler sensor location is determined using the DIP switch on the back of
the circuit board. If the DIP switch is set to ON, the boiler sensor is to be located on the boiler supply. If the DIP switch is set to OFF, the
boiler sensor is to be located on the boiler return.
• If the DIP switch is set to On, the RMC will “Control“ the boiler.
• If the DIP switch is set to Off, the RMC will “Enable” the boiler.
• If the Boiler Sensor has not been installed, the RMC will “Enable” the boiler.
BOILER CONTROL
When the RMC controls the boiler, the RMC opens and closes the boiler contact in order to control the temperature of the boiler
supply water temperature. When the RMC is controlling the boiler temperature, the RMC will determine the boiler supply water
temperature that is required to satisfy the demands of the system. The RMC will also determine a differential that is sufficient to
minimize short cycling of the boiler. The RMC will then cycle the boiler using these parameters.
Differential
An on / off boiler must be operated with a differential in order to prevent short cycling. When the supply water temperature drops
1/2 of the differential below the required boiler supply temperature, the boiler is turned on. The boiler is then kept on until the supply
Com Heat
Dem
Boil Out



Unpowered Demand
The RMC recognizes an Unpowered Demand signal when a switch is closed between
the Com and Heat Dem terminals.
SYSTEM PUMP OPERATION
The RMC has an internal system pump contact. This contact turns on when the RMC has
a mixing demand. The system pump as well as an external boiler pump may be controlled
by this relay. By providing proper flow in the boiler loop, the boiler temperature can be
accurately controlled based on the mixing load.
Start
Time
120
110
100
90
80
70
60
50
40
30F
Supply Temperature (F)
Mix Target
Delta T Maximum
Mix Supply
Mix Return
Maximum Delta T
ON OFF
1
2
Injection Mixing Control

8
water temperature rises 1/2 of the differential above the required boiler supply temperature. If the differential is too wide, there can
be large supply water temperature swings; however, if the differential is too narrow, the boiler short cycles and operates ineffi-
ciently. This control automatically calculates the boiler differential in order to achieve an appropriate balance between temperature
swings and boiler efficiency. This also permits the control to adapt to changing loads and conditions.
The RMC only operates the boiler once the output of the injection circulator exceeds 10% of flow.
B






BOILER ENABLE
When the RMC “Enables” the boiler, the RMC opens and closes the boiler contact based on the output of the variable speed injection
pump. The actual temperature and cycling of the boiler is then determined by other controls or the aquastats on the boiler itself.
When operating in the boiler enable mode, the boiler contact turns on once the variable speed output exceeds 25%. The boiler
contact shuts off if the output of the variable speed drops below 5% for more than three minutes or if the demand is removed from the
RMC.






BOILER PROTECTION (BOILER MINIMUM)
Cool water is often returned to the boiler from low temperature radiant floor heating systems or when the heating system is recovering
from night setback. This cool boiler return water may cause the boiler to operate at such a low temperature that the flue gases
condensH. Alternatively, when the boiler surfaces are hot due to previous loads such as domestic hot water generation, the large
temperature difference (Delta T) between the boiler and its return water can cause the boiler to become thermally shocked. Proper
protection of the boiler under these circumstances is required.
When a boiler sensor is connected to the control, the RMC is capable of providing boiler protection. When providing boiler protection,
the RMC limits the output of the variable speed injection pump in order to reduce the amount of cool water being returned to the boiler.
This allows the boiler temperature to increase to a point that avoids flue gas condensation.
B






Boiler Protection with Boiler Enable
When the Boiler Sensor is set to the “Return” setting the control begins to back off the variable speed injection pump when the
boiler temperature drops below the Boiler Minimum Setting.
Boiler Protection with Boiler Control
When the Boiler Sensor is set to the “Supply” setting the control begins to back off the variable speed injection pump when the
boiler temperature drops 1/2 of the Differential below the Boiler Minimum Setting.
Note: If a boiler sensor is not installed, the RMC cannot provide boiler protection.
C






CAUTION
Improper installation and operation of this product could result in damage to the equipment and possibly personal injury. It is your
responsibility to ensure that this product is installed in a safe manner according to all of the applicable codes, standards and instruc-
tions. The electronic control contained in this product is not intended as a primary limit control. Removal of the PC Board from its
enclosure can result in damage to the control and possibly even personal injury. Refer to qualified personnel for servicing.
S
Set Up of Radiant Mixing Control






STEP ONE - REMOVING THE RADIANT MIXING CONTROL FROM THE RADIANT MIXING BLOCK
• Remove the screw from the front of the control.
• Grasp the front of the control and remove it from the green plastic enclosure surrounding the injection mixing block.
• Wiring to the control is connected to the back of the circuit board using either the indicated spade connectors, molex connectors or
the snap on terminal plugs. These may need to be disconnected to fully remove the control.
STEP TWO - INSTALLING THE SENSORS
Outdoor Sensor
Note: The temperature sensor is built into the plastic enclosure.
If the Radiant Mixing Block is to be used in the outdoor reset mode, the Outdoor Sensor must
be installed. If the Radiant Mixing Block is to be used in either the setpoint or a delta T mode,
the Outdoor sensor is not required and does not need to be installed. (See pages 5 to 7 for a
complete description of the available modes.)
• Remove the screw from the center of the sensor and pull the front cover off of the sensor.
• The outdoor sensor can either be mounted directly to an outside wall or onto a standard
electrical box. Wiring can enter the sensor either through the bottom or the back of the plastic
enclosure.
• The sensor should be mounted on a wall which best represents the heat load on the building
(i.e. a north facing wall for most buildings and a south facing wall for building with a large south
facing glass area). The sensor should not be installed near heat sources such as exhaust
vents or window openings.
• The sensor should be installed at an elevation above the ground that will prevent accidental
damage or tampering.
• Ensure that the sensor is installed in a sheltered location out of direct sunlight and rain.
• Connect a two conductor wire to the terminal block in the Outdoor Sensor and run the wires
from the Outdoor Sensor back to the Radiant Mixing Control’s location.
I

9
Installing the System and Boiler Sensors
Note: These sensor are designed to be mounted on a pipe or in a temperature well.
• These sensors can be strapped directly to the pipe using the cable tie provided with the
sensors. Insulation should be installed around the sensors to reduce the effect of air currents
on the temperature measurement. Care should be taken not to over-tighten the cable tie as
this can cause damage to the sensor.
• The System Supply Sensor is to be installed on the System Supply pipe. This sensor is
required at all times.
• If a Boiler Sensor is used, install the boiler sensor on either the boiler supply or the boiler
return. Ensure that the DIP switch on the back of the circuit board of the RMC is set to ON if the
sensor is installed on the boiler supply and set to OFF if the sensor is installed on the boiler
return. If boiler control and boiler protection are not required in the application, the boiler
sensor does not need to be installed.
• If a System Return Sensor is to be used, install the sensor on the system return pipe. This
sensor is only required if the RMC is operating in the Delta T mode.
S
STEP THREE - WIRING THE RMC
• Before wiring the control, ensure that power to all circuits is off.
• Ensure that all wires are stripped to a minimum of 3/8” (9 mm) in order to ensure proper connection to the low voltage terminals.
• Provide a separate circuit with a minimum 15 A capacity in order to insure proper operation.
Wiring Power to the RMC
Using the supplied line cord, connect the white wire with the 1/4 inch female
spade connector to the 1/4 inch male spade connector labelled “N” on the
back of the RMC circuit board. Connect the black wire with the 1/4 inch
female spade connector to the 1/4 inch male spade connector labelled “H”
on the back of the RMC circuit board. Connect the green wire to the ground
screw located on the casting of the Radiant Mixing Block.
Wiring to the Radiant Mixing Block
Wiring to the Injection Pump
Connect the variable speed injection pump’s three pin molex connector
from the Radiant Mixing Block to the matching three pin molex connector
labelled “Var” on the back of the RMC circuit board.
Wiring the Radiant Mixing Block System Pump
Connect the system pump’s four pin molex connector from the Radiant
Mixing Block to the matching four pin molex connector labelled “Sys” on
the back of the RMC circuit board.
Sys H
Pmp
Use copper
conductors only
Power: 120 V +/- 10%
50/60 Hz, 750 VA
Var. Speed: 120 V
(ac) 1A
Pmp Relay: 120 V
(ac) 5 A, 1/6 hp
Injection Mixing
967-01
Meets Class B
Canadian ICES
FCC Part 15
ON OFF
1
2
3
4
5
CUS
158033
BOILER
R
Com Sup Sys
Ret
Com Boil Out Com Heat
Dem
Made in Canada
Var
T1A 250V
Sys
Man
N
H
Pmp
Use copper
conductors only
Power: 120 V +/- 10%
50/60 Hz, 750 VA
Var. Speed: 120 V
(ac) 1A
Pmp Relay: 120 V
(ac) 5 A, 1/6 hp
Injection Mixing
967-01
Meets Class B
Canadian ICES
FCC Part 15
ONOFF
1
2
3
4
5
CUS
158033
BOILER
R
STEP TWO - (continued)
Wiring the Sensors
Do not apply power to the sensors or the sensor terminals as this will damage either the sensors or the control.
Begin by removing the eight (8) pin plug-in terminal block from the RMC’s circuit board. To do this, pull the terminal block directly
away from the circuit board.
System Supply Sensor (Required)
Connect the two wires from the System Supply Sensor directly to the “Com” and “Sup”
terminals of the terminal block. The System Supply Sensor is used to measure the
supply temperature being delivered to the system.
System Return Sensor (Delta T Limiting Mode)
Connect the two wires from the System Return Sensor directly to the “Com” and “Sys
Ret” terminals of the terminal block. The System Return Sensor is used to measure the
return temperature from the system.
Boiler Sensor (Optional)
Connect the two wires from the Boiler Sensor directly to the “Com” and “Boil” terminals
of the terminal block. The Boiler Sensor is used to measure the boiler temperature.
Outdoor Sensor (Reset Mode)
Connect the two wires from the Outdoor Sensor directly to the “Com” and “Out” termi-
nals of the terminal block. The outdoor sensor is used to measure the outdoor air tem-
perature.
Com Heat
Dem
Boil OutSys
Ret
ComCom Sup
Com Heat
Dem
Boil OutSys
Ret
ComCom Sup
Com Heat
Dem
Boil OutSys
Ret
ComCom Sup
Com Heat
Dem
Boil OutSys
Ret
ComCom Sup

10
Wiring the External Boiler Pump (Optional)
Using a 3/16 inch female spade connector, connect the hot side of the boiler pump circuit to the male spade connector labelled
“Pmp” located on the back of the RMC circuit board. Connect the neutral side of the boiler pump circuit to the neutral (N) side of the
RMB’s input power supply. When using this option the line cord should be removed and the RMB hard wired.
Wiring the Heat Demand (Required)
The Heat Demand circuit can be wired using either a powered signal or an unpowered switch closure.
Powered Demand
If a powered demand is being used, connect the switched side of the 24 V (ac) demand
circuit to the “Heat Dem” terminal of the terminal block. Connect the second side of the
24 V (ac) demand circuit to the “Com” terminal of the terminal block.
Unpowered Demand
If an unpowered demand is being used, connect one side of the demand switch to the
“Heat Dem” terminal of the terminal block. Connect the second side of demand switch
to the “Com” of the terminal block.
Wiring the Boiler
Begin by removing the two (2) pin plug-in terminal block from the RMC’s circuit board. To
do this, pull the terminal block directly away from the circuit board.
The Boiler Relay is a switch that is to be used in the boiler circuit. There is no power
available on these terminals from the RMC. Connect the Boiler relay in series with the
control circuit of the boiler.
S
Com Heat
Dem
Boil OutSys
Ret
ComCom Sup

STEP FOUR - RECONNECTING THE TERMINAL BLOCKS
Insert the eight (8) pin plug-in terminal block into the eight (8) pin terminal header on the RMC circuit board. Press firmly until it snaps
into place.
Insert the two (2) pin plug-in terminal block into the two (2) pin terminal header on the RMC circuit board. Press firmly until it snaps into
place.
STEP FIVE - MOUNTING THE RMC
• Begin by pushing all excesses wiring back into the Radiant Mixing Block.
• Place the RMC into the Radiant Mixing Block’s plastic enclosure.
• Insert the screw into the hole located on the face of the RMC and tighten the screw to fasten the RMC to the Radiant Mixing Block
Enclosure. Do not overtighten.
STEP SIX - POWERING THE RMC
Apply power to the RMC circuit by plugging in the line cord.
POWER UP
On power up, the control displays all segments for 2 seconds followed by the control version
number.
The control then automatically goes to the operating mode and displays either the outdoor
temperature or the mix supply temperature.
Display Operation
OUT
ROOM
TERM
Cls
MIX
MODE
INDR
T
MINMAX
DEM
VIEW ADJUST
TIME SCHD
FC
%
1!
MOTR UNOCC
AMPM
%
2
123
DHW 12
12 DHW
min
hr %
BOIL SUP
SETP TARG
RET
DIFFMASS
DSGN
STG MoTuWeThFrSaSu
XCHG F DLY BST PURG
Opn WWSD
O
VIEW MENU
To advance to the next available View Item, press and release the ITEM button on the face of the control.
Outdoor Temperature
The outdoor temperature is displayed when the OUTDR element is turned on. This is the
current temperature at the outdoor sensor. The outdoor temperature is only displayed if
an outdoor sensor is installed and the Outdoor Design temperature is not turned off.
Mixing Supply Temperature
The mixing supply temperature is displayed when the MIX SUP elements are turned on.
This is the current temperature at the mixing supply sensor.
M
OUT
DEM
VIEW
F
%
1
MIX
DEM
VIEW
F
%
1
SUP

11
Mixing Target Temperature
The Mixing Target Temperature sets the desired supply temperature when operating in
the setpoint mode. This item is only available if the Outdoor Design setting is set to OFF.
V
Mixing Return Temperature
The mixing return temperature is displayed when the MIX RET elements are turned on.
This is the current temperature at the mixing return sensor. The mixing return temperature
is only displayed if the Outdoor Design temperature is turned OFF and a mixing return
sensor is installed.
Mixing Target Temperature
The mixing target temperature is displayed when the MIX TARG elements are turned on.
This is the temperature the RMC is currently trying to maintain at the supply sensor.
If “- - -” is displayed, the RMC is either in WWSD or a demand for heat is not present.
Boiler Temperature
The boiler temperature is displayed when the BOIL element is turned on. This is the
current temperature at the boiler sensor. The boiler temperature is only displayed if a
boiler sensor is installed.
ADJUST MENU
To switch between the View menu and the Adjust menu, press and release the MENU button on the face of the control. To advance to
the next available Adjust Item, press and release the ITEM button on the face of the control.
O
MIX
DEM
VIEW
F
%
1
RET
MIX
DEM
VIEW
F
%
1
TARG
BOIL
DEM
VIEW
F
%
1
MIX
ADJUST
F
TARG
Delta T Maximum
The Delta T Maximum sets the maximum temperature difference between the mixing
return sensor and the mixing supply sensor. This item is only available if Outdoor Design
setting is set to OFF. If a mixing return sensor is not installed, set this item to OFF.
Outdoor Design Temperature
The Outdoor Design Temperature is the outdoor temperature used in the heat loss calcu-
lation. If the RMB is used in the outdoor reset mode, this item is set to the typical coldest
outdoor temperature. If the RMB is used in the setpoint mode, this item is set to OFF.
Mixing Design Temperature
The mixing design temperature is the supply temperature used in the heat loss calcula-
tion. This is the supply temperature that is required to heat the building when the outdoor
temperature is as cold as the outdoor design temperature. This item is only available if the
Outdoor Design setting is not set to OFF.
Mixing Maximum Temperature
The mixing maximum temperature is the highest temperature that the control is allowed to
use as a mixing target temperature. This item is only available if the outdoor design set-
ting is not set to OFF.
M
T
MAX
ADJUST
F
OUT
ADJUST
F
DSGN
MIX
ADJUST
F
DSGN
MIX
MAX
ADJUST
F
Mixing Minimum Temperature
The mixing minimum temperature is the lowest temperature that the control is allowed to
use as a mixing target temperature. This item is only available if the outdoor design set-
ting is not set to OFF.
B
MIX
MIN
ADJUST

12
Boiler Minimum Temperature
The boiler minimum temperature item should be set to the lowest water temperature at
which the boiler can operate without causing the boiler flue gases to condense. Consult
the boiler manufacturer for recommended minimum boiler supply temperatures. This item
is only available if a boiler sensor is connected to the control.
Warm Weather Shut Down (WWSD)
The warm weather shut down is the outdoor temperature at which the system is shut
down. This item is only available if the outdoor design temperature is not set to OFF.
Units
The units of temperature in which all of the View and Adjust items are viewed in.
The control automatically goes back to the view menu when the buttons are left alone for 20 seconds
All settings will be saved even during power down of the control
T
MIN
ADJUST
F
BOIL
ADJUST
F
WWSD
ADJUST
F
As in any troubleshooting procedure, it is important to isolate the problem as much as possible. By using the Error Messages located on
page 14, the trouble shooting process can be greatly simplified. When an error message is displayed on the RMC, refer to the error
messages on page 14 to identify the cause of the error and use standard testing procedures to confirm the fault. If you suspect an
external wiring fault, return to step three and carefully check all external wiring connections.
Once the fault has been corrected, press any button on the face of the control to clear the error message.
TEST ROUTINE
The main control functions of the RMC can be tested by pressing and holding the UP button for more than three (3) second. After the
UP button has been pressed for more than three (3) second, the RMC the follows the following sequence.
Step One
The variable speed output is increased from 0% to 100% over 10 seconds.
Step Two
The variable speed output is decreased from 100% to 0% over 10 seconds.
Step Three
The System Pump is turned on for 10 seconds.
Step Four
The Boiler Contact is turned on. After 10 seconds, the Boiler Contact and the
System Pump contact are turned off. The RMC continues normal operation.
MANUAL OVERRIDE
In the event that the RMC fails to operate, a manual operation switch is located on
the RMC’s circuit board. When the manual operation switch is set to Man, the
variable speed injection pump and the system pump outputs are turned on. This
operation continues until the manual switch is returned to its original position.
FUSE REPLACEMENT
The Variable Speed output of the RMC is fused protected. This fuse is located on
the circuit board on the back of the RMC. This is a field replaceable item.
Fuse rating: 1 A 1/12 hp, fuse T1 A 250 V
ADJUSTMENT OF SETTINGS
If the outdoor temperature is cold and the rooms are cold, increase the MIX DSGN
setting by 5°F (3°C) per day.
T
Trouble Shooting
Com Sup Sys
Ret
Com Boil Out Com Heat
Dem
Made in Canada
Var
T1A 250V
Sys
Man
N
H
Pmp
Use copper
conductors only
Power: 120 V +/- 10%
50/60 Hz, 750 VA
Var. Speed: 120 V
(ac) 1A
Pmp Relay: 120 V
(ac) 5 A, 1/6 hp
Injection Mixing
967-01
Meets Class B
Canadian ICES FCC Part 15
ON OFF
1
2
3
4
5
CUS
158033
BOILER
R
As in any troubleshooting procedure, it is important to isolate the problem as much as possible. By using the Error Messages located on
pages 13 &14, the trouble shooting process can be greatly simplified. When an error message is displayed on the RMC, refer to the
error messages on pages 13 &14 to identify the cause of the error and use standard testing procedures to confirm the fault. If you sus-
pect an external wiring fault, return to step three and carefully check all external wiring connections. Once the fault has been corrected,
press any button on the face of the control to clear the error message.

13
TESTING THE SENSORS
Do not apply voltage to the sensor or to the sensor input of the control as this will result in damage
to either the sensor, the control, or both the sensor and the control.
A quality testing meter capable of measuring up to 2,000,000 ohms and a good quality digital
thermometer are required to test the sensors. If a digital thermometer is not available, place a
second sensor next to the original sensor and compare the readings.
Begin by measuring the temperature at the sensor location using the digital thermometer. Next,
measure the resistance of the sensor using the testing meter. Ensure that the sensor is discon-
nect from the control at the time of testing. Using the reference chart below, determine the sensor’s
temperature. Compare the sensor’s temperature to that measured by the digital thermometer. The
two temperature readings should be close.
If the sensors temperature is too high, this can indicate that there is a partial short in the sensor
wiring. If the sensor’s temperature is too low, this can indicate that there is a loose connection or
break in the sensor wiring. Isolate and repair the problem. If the problem is isolated to the sensor,
replace the sensor.

-30
-20
-10
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
-34
-29
-23
-18
-12
-7
-1
4
10
16
21
27
32
38
43
49
54
60
66
71
77
82
88
93
234,000
165,000
118,000
85,500
62,500
46,000
34,500
26,000
20,000
15,500
12,000
9,300
7,300
5,800
4,700
3,800
3,100
2,500
2,000
1,700
1,400
1,200
1,000
800
Temperature Resistance
FCOhms
Temperature Resistance
FCOhms
Temperature Resistance
FCOhms
Temperature Resistance
FCOhms
EEPROM Read Error
The control was unable to read the in-
stallers settings from its memory. The
control was forced to load the factory
defaults for all settings. The control will
stop operation until all of the settings
in the Adjust menu have been checked.
O
Error Messages
VIEW
!
MIX
VIEW
!
RET
Mixing Return Sensor Short Circuit
A short circuit has been detected in the
mixing return sensor. If the Maximum
Delta T setting is set to OFF, the con-
trol continues operation. If the Maxi-
mum Delta T setting is not set to OFF,
the control stops operation until the
fault is corrected. To clear this error
message, correct the short circuit and
press any button on the control.
M
Outdoor Sensor Short Circuit
A short circuit has been detected in the
outdoor sensor. The control assumes
an outdoor temperature of 32°F (0°C)
and continues operation. To clear this
error message, correct the short circuit
and press any button on the control.
OUT
VIEW
!
MIX
VIEW
!
RET
Mixing Return Sensor Open Circuit
An open circuit has been detected in
the mixing return sensor. If the Maxi-
mum Delta T setting is set to OFF, the
control continues operation. If the Maxi-
mum Delta T setting is not set to OFF,
the control stops operation until the
fault is corrected. To clear this error
message, correct the open circuit and
press any button on the control.
B
Outdoor Sensor Open Circuit
An open circuit has been detected in
the outdoor sensor. The control as-
sumes an outdoor temperature of 32°F
(0°C) and continues operation. To clear
this error message, correct the open
circuit and press any button on the con-
trol.
OUT
VIEW
!
VIEW
!
BOIL
Boiler Sensor Short Circuit
A short circuit has been detected in the
boiler sensor. The boiler contact is
operated as if a boiler sensor is not
installed. The control provides a boiler
enable and does not provide boiler pro-
tection. To clear this error message,
correct the short circuit and press any
button on the control.

14
Technical Data
1
PERFORMANCE DATA
Flow Range: .................................................. 0 - 15.5 GPM
Head Range: ................................................. 0 - 15 Feet
Minimum Fluid Temperature: ........................ 32°F (0°C)
Maximum Fluid Temperature:.......................18°F (85°C)
Maximum Working Pressure: ........................ 125 psi
Connections: ................................................. 3/4" NPT
C US UL Mark
FOR INDOOR USE ONLY
MATERIALS OF CONSTRUCTION
Casing (body):...............................................6WDLQOHVV6WHHO
Stator Housing: ............................................. Steel
Cartridge: ...................................................... Stainless Steel
Impeller: ........................................................ Non-Metallic
Shaft: ............................................................. Ceramic
O-Ring & Gaskets: ........................................ EPDM
ELECTRICAL DATA CHART
Volts .............................................................. 120
Hz .................................................................. 60
Ph .................................................................. 1
Amps ............................................................. 2
RPM .............................................................. 3250
HP ................................................................. 1/40 & 1/25
Motor Type....................................................Permanent Split
&DpacitorImpedance Protected
CONTROL ADJUSTMENT MENU
Mixing Setpoint Temperature ........................ 60°to 185°F
Maximum Temperature Difference
Between Mixing Supply and Return ............. 10°to 70°F, Off
Design Outdoor Air Temperature ................... -60°to 32°F, Off
Design Heating System Supply Water
Tem p e rat u r e ... . . ... . . ... . . ... . . ... . . ... . . ... . . ... . . ... . . ... . . 7 0 °to 185°F
Maximum Mixing Target Supply .................... 80°to 185°F
Minimum Mixing Target Supply
Fluid Temperature ......................................... 35°to 150°F, Off
Minimum Boiler Target Supply
Water Temperature ....................................... 80°to 180°F, Off
Warm Weather Shut Down ........................... 35°to 100°F, Off
Units .............................................................. °C or °F
(QFORVXUH&RPSRVLWH
&(57,),&$7,216$1'/,67,1*6
NSF
Certified to
NSF/ANSI 372
®
Mixing Supply Sensor Short Circuit
A short circuit has been detected in the
mixing supply sensor. The control con-
tinues to operate the injection pump at
a low speed (17 - 18%) as long as a
demand is present. To clear this error
message, correct the short circuit and
press any button on the control.
Mixing Supply Sensor Open Circuit
An open circuit has been detected in
the mixing supply sensor. The control
continues to operate the injection pump
at a low speed (17 - 18%) as long as a
demand is present. To clear this error
message, correct the open circuit and
press any button on the control.
MIX
VIEW
!
SUP
MIX
VIEW
!
SUP
VIEW
!
BOIL
Boiler Sensor Open Circuit
An open circuit has been detected in
the boiler sensor. The boiler contact is
operated as if a boiler sensor is not
installed. The control provides a boiler
enable and does not provide boiler pro-
tection. To clear this error message,
correct the open circuit and press any
button on the control. If the sensor was
deliberately removed, power down the
control for five (5) seconds and re-
power the control.
Fax: [phone]
V
RMC - Radiant Mixing Control (Variable Speed)
Control - Microprocessor PID control: This is not a safety (limit)
control
Ambient conditions - Indoor use only, 32 to 185°F (0 to 85°C), <90% RH non-
condensing
Power Supply - 120 V (ac) +/- 10% 50/60 Hz 720 VA
Var. Pump - 120 V (ac) 1 A 1/12 hp, fuse T1 A 250 V
Sys / Pmp Relay - 120 V (ac) 5 A 1/4 hp, pilot duty 240 VA
Boiler Relay - 120 V (ac) 5 A 1/4 hp, pilot duty 240 VA
Demand - 24 V (ac) 0.1 VA or Dry contact
Sensors - NTC thermistor, 10 kohm @ 77°F (25C +/- 0.2°C) B=3892
Included - Taco Outdoor Sensor and 2 Taco Strap-on Sensors
The installer must ensure that this control and its wiring are isolated and/or shielded from strong sources of electromagnetic noise.
Conversely, this Class B digital apparatus complies with Part 15 of the FCC Rules and meets all requirements of the Canadian Interfer-
ence-Causing Equipment Regulations. However, if this control does cause harmful interference to radio or television reception, which
can be determined by turning the control off and on, the user is encouraged to try to correct the interference by reorienting or relocating
the receiving antenna, relocating the receiver with respect to this control, and/or connecting the control to a different circuit from that to
which the receiver is connected.
MIX SUP
DEM
VIEW
F
%
1
ITEM
MENU
RADIANTMIXINGBLOCK
PATENT PENDING RMB-1
TM
UL
R
CUS
Telephone: [phone] FAX: [phone].
T Telephone: [phone]. FAX: [phone].
V

15
Fax: [phone]
V
Cleaning
The exterior of the control can be cleaned using a damp cloth. Do not use any solvents. Moisten the cloth and wring out any excess
water before cleaning the control.
Telephone: [phone] FAX: [phone].
T Telephone: [phone]. FAX: [phone].
V
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Mixing Supply and Return ............. 10°
DIMENSIONS & WEIGHT
Model: RMB-1 Ship Weight: 18.5 lbs (8.4 kg)
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Replacing Cartridge Assembly
1. Disconnect the electrical supply.
2. Reduce system pressure to 0 psi and allow system to return to room temperature. Isolate the RMB by closing the service valves or
draining the system.
3. Remove the body bolts and swing motor assembly away from the body.
4. Pull cartridge out of the motor housing.
5. Install replacement cartridge, making sure that the cover plate is between the cartridge flange and motor.
6. Make sure the replacement cartridge corresponds to the full circulator product number. A complete parts list is available from your
local plumbing supply wholesaler.
7. Reassemble the circulator using the new gasket and bolts supplied.
8. Follow the “Installation” procedure to start up the circulator.
M
1. Disconnect the electrical supply.
2. Reduce system pressure to 0 psi and allow system to return to room temperature. Isolate the Radiant Mixing Block by closing the
service valves or draining the system.
3. Remove the Boiler Supply connection to the Radiant Mixing Block.
4. Remove snap ring.
5. Remove the check valve, using needle nose pliers.
6. Install replacement check valve by pressing the valve into the casing until it is firmly seated.
7. Install the snap ring.
8. Reconnect the Boiler Supply connection to the Radiant Mixing Block.
9. Follow the “Installation” procedure to start up the Radiant Mixing Block.
Replacing the Check Valve
P
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Mixing Supply and Return ............. 10°
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16
008 MOTOR
CONNECTION FROM
CONNECTION FROM
LINE (BLACK)
006 MOTOR
CONNECTION FROM
QUICK DISCONNECT
CONNECTION FROM
NEUTRAL (WHITE)
INSTALL ADDITIONAL
IMC
LINE & NEUTRAL
IF C
A
CONNECTIONS
GROUND SCREW
COVE R
IMC
ASSEMBLY
CASING
BACK COVER
AIR VENT
GROUND
CONNECTION
BODY BOLTS (8)
1. Control Board
2. Outdoor Sensor
3. Strap-On Sensor
4. Top Injection Pump Cartridge
5. Bottom System Pump Cartridge
6. Top Injection Pump Motor Only
Replacement Parts Breakdown
LIMITED WARRANTY STATEMENT
Taco, Inc. will repair or replace without charge (at the
company’s option) any product or part which is proven
defective under normal use within one (1) year from the
date of startup or one (1) year and six (6) months from
the date of shipment (whichever occurs first). Taco, Inc.
will repair or replace without charge (at the company’s
option) any Taco 00 Series circulator cartridge that is
proven defective under normal use within three (3) years
from the date of manufacture.
In order to obtain service under this warranty, it is the re-
sponsibility of the purchaser to promptly notify the local
Taco stocking distributor or Taco in writing and promptly
deliver the subject product or part, delivery prepaid, to the
stocking distributor. For assistance on warranty returns,
the purchaser may either contact the local Taco stocking
distributor or Taco. If the subject product or part contains
no defect as covered in this warranty, the purchaser will
be billed for parts and labor charges in effect at time of
factory examination and repair.
Any Taco product or part not installed or operated in con-
formity with Taco instructions or which has been subject
to misuse, misapplication, the addition of petroleum-
based fluids or certain chemical additives to the systems,
or other abuse, will not be covered by this warranty.
If in doubt as to whether a particular substance is suitable
for use with a Taco product or part, or for any application
restrictions, consult the applicable Taco instruction
sheets or contact Taco at (401-942-8000).
Taco reserves the right to provide replacement products
and parts which are substantially similar in design and
functionally equivalent to the defective product or part.
Taco reserves the right to make changes in details of de-
sign, construction, or arrangement of materials of its
products without notification.
TACO OFFERS THIS WARRANTY IN LIEU OF ALL
OTHER EXPRESS WARRANTIES. ANY WARRANTY
IMPLIED BY LAW INCLUDING WARRANTIES OF
MERCHANTABILITY OR FITNESS IS IN EFFECT ONLY
FOR THE DURATION OF THE EXPRESS WARRANTY
SET FORTH IN THE FIRST PARAGRAPH ABOVE.
THE ABOVE WARRANTIES ARE IN LIEU OF ALL
OTHER WARRANTIES, EXPRESS OR STATUTORY,
OR ANY OTHER WARRANTY OBLIGATION ON THE
PART OF TACO.
TACO WILL NOT BE LIABLE FOR ANY SPECIAL, INCI-
DENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES
RESULTING FROM THE USE OF ITS PRODUCTS OR
ANY INCIDENTAL COSTS OF REMOVING OR RE-
PLACING DEFECTIVE PRODUCTS.
This warranty gives the purchaser specific rights, and the
purchaser may have other rights which vary from state
to state. Some states do not allow limitations on how long
an implied warranty lasts or on the exclusion of incidental
or consequential damages, so these limitations or exclu-
sions may not apply to you.
1.
11.
9. 10.
or
6.
7.
4.
5.
8.
193-004RP
9300-2052RP
9300-2044RP
005-020RP
008-045RP
193-015RP
7. Bottom System Pump Motor
8. Only Air Vent
9. Check Valve Dated 6/05 or Older
10. Check Valve Dated 7/05 or ewer
11. Brown Button Fuse
193-016RP
419-1
193-003RP
193-030RP
26-784RP
Replacement Parts