Price acutherm BACnet EF Series User manual

v001 –Issue Date: 12/02/22
© 2022 Acutherm. All rights reserved.
MANUAL – INSTALLATION, OPERATION + MAINTENANCE
BACnet™ Motorized VAV Diffuser
EF Series

acutherm.com | BACNET™ MOTORIZED VAV DIFFUSER - Manual
BACNET™ MOTORIZED VAV DIFFUSER
BACNET™ MOTORIZED VAV DIFFUSER - Manual | acutherm.com
TABLE OF CONTENTS
Installation Instructions.................................................. 1
System Balancing......................................................... 3
Trouble Shooting........................................................... 4
Maintenance & Controlling the System.......................... 7
Two Year Warranty........................................................ 8

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acutherm.com | BACNET™ MOTORIZED VAV DIFFUSER - Manual
BACNET™ MOTORIZED VAV DIFFUSER
INSTALLATION INSTRUCTIONS
Damaged Freight Claim Procedure
When the diffusers are received, inspect for damage, which
may have occurred during shipment. If damage is evident, it
should be noted on the carrier’s freight bill. A written request
for inspection by the carrier’s agent should be made at once.
Storage
Cartons should always be stacked on end with the arrows
on the cartons pointing up. Do not stack cartons flat on the
sides. Excessive weight may cause damage to the diffusers.
Do not store for prolonged times at temperatures exceeding
130˚F/56˚C. Acceptable humidity level 5-95% relative humidity
noncondensing.
Identification
Models are factory shipped one per carton. The model
designation is on the diffuser and on the carton.
Installation Precautions
When installing diffusers make sure construction debris does not enter the diffuser or duct system. Because the EF-B controls
room temperature by sensing the air induced up the center of the room, care should be taken not to disturb room air induction and
entrainment. For example, location next to walls or dropped lights results in the reflection of supply air back at the Therma-Fuser
diffuser and should be avoided. A three way blow Therma-Fuser diffuser should be used in this instance if either the light or the
Therma-Fuser diffuser cannot be relocated.
Power Requirements
24 +3/-1VAC 10VA max.
Installation
1. Inspect the carton for damage before opening. Notify carrier if external damage exists. Submit all claims for shipping damage
to the carrier.
2. Move diffusers (in cartons) to installation area. Note unit identification.
3. Remove cardboard box and cardboard insert. Recycle packing material.
4. If other than 4 way blow pattern is installed note the “AIRFLOW” markings on the top of the diffuser and locate those sides in
the proper direction.
5. Install in ceiling grid. Install T-bar support wire close to each corner of diffuser. Make sure that only wire suspended T-bars are
used to support diffuser weight. Follow all local codes for seismic restraints. (Adaptor frames are available for other than lay in
ceilings.)
6. Connect and secure the supply duct to the collar. Flexible duct should NOT be formed in a centerline radius of less than 1½
times the duct diameter.
7. Connect shielded twisted pair network wiring to the screw terminals labeled (+) and (-) and connect the drain wire to COM
(see Fig. 7 Wiring Diagram). All network wiring should be to ASHRAE Standard 135 and EIA-485.
8. Connect 24 VAC power to the screw terminal labeled 24VAC (POWER IN) (see Fig. 5 Wiring Diagram).
9. Commission all EF-B diffusers (see BACnet Object List Form 091.202).
10. Balance the system (see System Air Balancing below).
FIG. 1 DIMENSIONS
NOMINAL
NECK
SIZE (in.)
OD
Inches
±1/16
mm
±3
6 515/16 150
8 715/16 200
10 915/16 250
12 1115/16 300
FORM 091.205 REV 1403
EF-B-M BACnet™ MOTORIZED VAV DIFFUSER
INSTALLATION, OPERATION AND MAINTENANCE
Copyright © Acutherm 2014 Page 1 of 6
SQUARE
*23
3
/
4
±
1
/
16
" - 603±2mm
OD 1
1
/
2
±
1
/
8
" - 38±3mm
4
5
/
8
±
1
/
8
"
118±3mm
13
/
16
±
1
/
16
"
20±2mm
LIP
NECK SECTION
*595±2mm Square with 16±2mm lip available
–specify 595mm square.
5
15
/
16
NOMINAL
NECK
SIZE
6"
Inches
±
1
/
16
"
7
15
/
16
9
15
/
16
11
15
/
16
8"
10"
12"
mm
±3
OD
150
200
250
300
Models: EF-B-M BACnet Interoperable Motorized
Square VAV Diffuser
CONTENTS
CONTENTS ............................................................................ 1
DAMAGED FREIGHT CLAIM PROCEDURES ..................... 1
STORAGE ............................................................................... 1
IDENTIFICATION ................................................................... 1
INSTALLATION PRECAUTIONS .......................................... 1
POWER REQUIREMENTS..................................................... 1
INSTALLATION...................................................................... 1
COMMISSIONING ................................................................ 2
POWER FAILURE................................................................... 2
AIR DENSITY COMPENSATION ......................................... 2
SYSTEM AIR BALANCING ................................................... 2
TROUBLESHOOTING............................................................ 2
System ................................................................................ 3
Conditions Outside the EF-B.......................................... 3
EF-B Properties ................................................................. 3
EF-B Electrical.................................................................... 4
MAINTENANCE..................................................................... 4
CONTROLLING THE SYSTEM ............................................. 4
Supply Air Temperature .................................................. 5
Static Pressure................................................................... 5
TWO YEAR WARRANTY ...................................................... 6
DAMAGED FREIGHT CLAIM PROCEDURES
When the diffusers are received, inspect for damage,
which may have occurred during shipment. If damage
is evident, it should be noted on the carrier’s freight
bill. A written request for inspection by the carrier’s
agent should be made at once.
STORAGE
Cartons should always be stacked on end with the
arrows on the cartons pointing up. Do not stack
cartons flat on the sides. Excessive weight may cause
damage to the diffusers. Do not store for prolonged
times at temperatures exceeding 130˚F/56˚C.
Acceptable humidity level 5-95% relative humidity
noncondensing.
IDENTIFICATION
Models are factory shipped one per carton. The
model designation is on the diffuser and on the
carton.
INSTALLATION PRECAUTIONS
When installing diffusers make sure construction
debris does not enter the diffuser or duct system.
Fig. 1 Dimensions
Because the EF-B controls room temperature by
sensing the air induced up the center of the room,
care should be taken not to disturb room air
induction and entrainment. For example, location next
to walls or dropped lights results in the reflection of
supply air back at the Therma-Fuser diffuser and
should be avoided. A three way blow Therma-Fuser
diffuser should be used in this instance if either the
light or the Therma-Fuser diffuser cannot be
relocated.
POWER REQUIREMENTS
24
+3
/
-1
VAC 10VA max.
INSTALLATION
1. Inspect the carton for damage before opening.
Notify carrier if external damage exists. Submit all
claims for shipping damage to the carrier.
2. Move diffusers (in cartons) to installation area.
Note unit identification.
3. Remove cardboard box and cardboard insert.
Recycle packing material.
4. If other than 4 way blow pattern is installed note
the “AIRFLOW” markings on the top of the
diffuser and locate those sides in the proper
direction.
5. Install in ceiling grid. Install T-bar support wire
close to each corner of diffuser. Make sure that
only wire suspended T-bars are used to support

2acutherm.com | BACNET™ MOTORIZED VAV DIFFUSER - Manual
BACNET™ MOTORIZED VAV DIFFUSER
INSTALLATION INSTRUCTIONS
BACNET™ MOTORIZED VAV DIFFUSER - Manual | acutherm.com
Commissioning
The EF-B unit is shipped with default values and will start to operate once power is supplied.
1. To establish communication, switch dip switch AUTOM ‘off’ and set the MAC address using the seven dip switches labeled 1
through 64 using standard seven bit addressing (i.e. 1 ‘on’ is 1, 1 ‘off’ and 2 ‘on’ is 2, 1 ‘on’ and 2 ‘on’ is 3, etc…).
2. Turn on the 24VAC supply power.
3. Discover (“who is”) the EF-B using preferred BACnet software.
4. Re-assign the Instance Number (ID Number) as required by the specific network. (A random instance number is assigned at
the factory.)
5. Refer to the EF-B Object List (Form 091.202) and configure the different properties of the EF-B as required by the project.
Power Failure
Objects designated as Configuration are stored in non-volatile memory so that the EF-B diffusers can resume normal operation
when power is restored after failure. See the EF-B Object List (Form 091.202) for a complete list of the Configuration Objects.
Air Density Compensation
Installation at altitudes above 1650ft / 503m requires modified settings for air density effects (see BACnet Object List Form
091.202).

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acutherm.com | BACNET™ MOTORIZED VAV DIFFUSER - Manual
BACNET™ MOTORIZED VAV DIFFUSER
SYSTEM AIR BALANCING
VAV systems are balanced for design air volume at maximum air flow and systems using Therma-Fuser VAV diffusers are no
exception. When all the Therma-Fuser diffusers are set for maximum airflow by fully opening them, the system is really a constant
air volume system and is balanced as a constant volume system. Balancing dampers are best located at the takeoff before the run
out to the diffuser.
1. Prepare system for balancing. (Make necessary checks for diversity, fan capacities, fan rotation, minimum outside air
requirements, duct leaks and static pressure controller design setting. Set outside air control damper for minimum air and
return air control damper for maximum air.)
2. Open EF-B diffusers for balancing.
a. The EF-B-M is shipped in the open position and will remain open until power is connected.
or
b. Set the value of the Object analog_value_25 (iOverride) to ‘1’. Allow 1-2 minutes for all diffusers to open fully.
3. Start fans, adjust system for 100% air flow and make system checks. (Measure static pressure across filters and coils and at
sensor for static pressure controller. Measure supply, return and branch duct air flow.)
4. Measure air flow from each EF-B diffuser and adjust the damper at the duct takeoff to obtain maximum design air flow. Air
flow measurement may be with a direct reading diffuser balancing hood or air velocity meter. In either case, measurements are
made with all appearance panels in place. This is because the appearance panel affects pressure drop through the diffuser.
When velocity meter is used to measure the discharge velocity, the velocity is measured at the top edge of the housing.
5. When balancing is complete, return each model EF-B diffuser to normal operation by setting the value of the Object analog_
value_25 (iOverride) to ‘0’.
NOTE: Diffuser noise is caused by higher velocity air through the diffuser which is caused by a high static pressure. Acutherm
recommends a static pressure no higher than 0.25”wg / 62Pa at the inlet to the diffuser. Some system designers may accept
higher noise levels and opt for a higher static pressure. Care should be taken not to exceed the design maximum static pressure at
the takeoff to the first EF-B diffuser after the static pressure control or, if none, after the fan.

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BACNET™ MOTORIZED VAV DIFFUSER
BACNET™ MOTORIZED VAV DIFFUSER - Manual | acutherm.com
TROUBLE SHOOTING
Trouble shooting Therma-Fuser diffusers requires looking at the system as a whole. Before examining the Therma-Fuser diffuser for
failure it is worth the time to be sure the system is functioning properly and that something has not been overlooked. Before calling
Acutherm, please complete the data log for all Therma- Fuser diffusers to be evaluated.
System
The system should be:
1. Delivering 50º-68ºF/ 10º-20ºC supply air when in the
cooling mode.
2. Delivering 80º-120ºF/ 26.5º-49ºC supply air when in the
heating mode.
3. Maintaining a constant supply air temperature.
4. Maintaining static pressure at the inlet to each Therma-
Fuser diffuser between .05 and .25”wg / 12 and 62Pa.
5. Maintaining continuous fan operation during occupied
hours.
Once the above checks have been completed examine and record the following:
Conditions Outside the EF-B
6. Room temperature 4ft/1200mm above the floor directly
under the Therma-Fuser diffuser.
7. Supply air temperature at the Therma-Fuser diffuser.
(Temperature may vary over time. Several measurements at
different times may be required.)
8. Static pressure at the inlet of the Therma-Fuser diffuser.
Conditions Outside the EF-B
9. Check that 24+3/-1VAC is supplied to the diffuser across the terminals labeled 24VAC (POWER IN) (see Fig. 5 Wiring
Diagram).
10. Determine the current set point.
a. Use a computer on the network with BACnet network management software to select the specific EF-B unit.
b. Discover the diffuser Objects and locate analog_input_3 (oEffectStpt). The value of this Object is the current set point for
the EF-B unit.
c. Check that other Objects are not overriding the current set point or limiting flow. The following are Objects that can
override normal operation and the default setting for each.
i. binary_value_0 (iVancancy Mode) = 0
ii. analog_value_0 (cMaxFlow) = 1000
iii. analog_value_1 (cMinFlow) = 0
iv. analog_value_2 (cMinStbyFlow) = 0
v. analog_values_4-9 (set points)
vi. analog_value_10 (cStPtLimit) = 2
vii. analog_value_11 (cStPtReset) = 0
viii. analog_value_12 (cMaxHeatsp) = 100
ix. analog_value_13 (cHCMode) = 0
x. analog_value_15 (cVacSpOfst) = 2
xi. analog_value_21 (iOccMode) = 0
xii. analog_value_22 (iHCMode) = 0
xiii. analog_value_23 (iTempSetpt) = 3276
xiv. analog_value_24 (iFlowSetpt) = 3276
xv. analog_value_25 (iOverride) = 0
xvi. analog_value_26 (iRmTemp) = 327
xvii. analog_value_27 (iSATemp) = 327
xviii.analog_value_28 (iFlowRate) = 3276
xix. analog_value_29 (iCO2Level) = 0
If they are other than as shown above, temporarily remove the override to make the Objects normal before further checking.

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BACNET™ MOTORIZED VAV DIFFUSER
TROUBLE SHOOTING
Conditions Outside the EF-B Cont'
11. Measure the damper blade opening from the edge of the
housing perpendicular to the housing (see Fig. 2 Blade
Opening).
12. Use the information from the steps above to determine if
the damper blades are correct for the conditions.
a. Determine mode. The EF-B unit should be in cooling if
the supply air temperature is below the set point. It is
in heating if the supply air temperature is above both
the room temperature and the set point.
b. For room temperatures more than 2ºF/1.2ºC from
set point, damper blades should be moving to the
position as shown in the Fig. 3 Troubleshooting.
NOTE:
i. Room temperature more than ±2ºF/1.2ºC from
set point has been selected as a general rule
of thumb for trouble shooting to avoid more
complicated control algorithms within that band.
Control is intended to be tighter but will depend
on system conditions.
ii. If any of the set points are changed to achieve
full open or full closed conditions, wait 5 to 10
minutes to make sure the room and system have
stabilized.
iii. For room temperatures less than 2ºF/1.2ºC from
set point, the damper blades may be somewhere
between open and closed.
13. If the damper blades are not according to the table,
check if there are maximum or minimum flow settings
or any other overrides limiting opening or closing? See
step 10.c. above. Record any maximum or minimum flow
settings or other overrides and return to that setting after
troubleshooting. For troubleshooting, reset maximum flow
to 1000 and minimum flow to 0. Wait 5 to 10 minutes –
see step 12.b.,note ii.
14. If there are no limiting flow stops or overrides complete
EF-B Electrical below before contacting Acutherm.
FIG. 2 BLADE OPENING
FIG. 3 TROUBLESHOOTING
Cooling Heating
Room Temp
vs
Set Point
+2ºF / 1.2ºC -2ºF / 1.2ºC +2ºF / 1.2ºC -2ºF / 1.2ºC
Damper Blade
Position Open Closed Closed Open
FORM 901.205 REV 1403
(Supersedes nothing)
Page 3 of 6
System
The system should be:
1. Delivering 50º-68ºF/ 10º-20ºC supply air when in
the cooling mode.
2. Delivering 80º-120ºF/ 26.5º-49ºC supply air when
in the heating mode.
3. Maintaining a constant supply air temperature.
4. Maintaining static pressure at the inlet to each
Therma-Fuser diffuser between .05 and .25”wg /
12 and 62Pa.
5. Maintaining continuous fan operation during
occupied hours.
Once the above checks have been completed examine
and record the following:
Conditions Outside the EF-B
6. Room temperature 4ft/1200mm above the floor
directly under the Therma-Fuser diffuser.
7. Supply air temperature at the Therma-Fuser
diffuser. (Temperature may vary over time. Several
measurements at different times may be required.)
8. Static pressure at the inlet of the Therma-Fuser
diffuser.
EF-B Properties
9. Check that 24+3/-1VAC is supplied to the diffuser
across the terminals labeled 24VAC (POWER IN)
(see Fig. 5 Wiring Diagram).
10.Determine the current set point.
a. Use a computer on the network with BACnet
network management software to select the
specific EF-B unit.
b. Discover the diffuser Objects and locate
analog_input_3 (oEffectStpt). The value of this
Object is the current set point for the EF-B unit.
c. Check that other Objects are not overriding the
current set point or limiting flow. The following
are Objects that can override normal operation
and the default setting for each.
i. binary_value_0 (iVancancy Mode) = 0
ii. analog_value_0 (cMaxFlow) = 1000
iii. analog_value_1 (cMinFlow) = 0
iv. analog_value_2 (cMinStbyFlow) = 0
v. analog_values_4-9 (set points)
vi. analog_value_10 (cStPtLimit) = 2
vii. analog_value_11 (cStPtReset) = 0
viii. analog_value_12 (cMaxHeatsp) = 100
ix. analog_value_13 (cHCMode) = 0
x. analog_value_15 (cVacSpOfst) = 2
xi. analog_value_21 (iOccMode) = 0
xii. analog_value_22 (iHCMode) = 0
xiii. analog_value_23 (iTempSetpt) = 3276
xiv. analog_value_24 (iFlowSetpt) = 3276
xv. analog_value_25 (iOverride) = 0
xvi. analog_value_26 (iRmTemp) = 327
xvii. analog_value_27 (iSATemp) = 327
xviii. analog_value_28 (iFlowRate) = 3276
xix. analog_value_29 (iCO2Level) = 0
If they are other than as shown above,
temporarily remove the override to make the
Objects normal before further checking.
Fig. 2 Blade Opening
11.Measure the damper blade opening from the edge
of the housing perpendicular to the housing (see
Fig. 2 Blade Opening).
12.Use the information from the steps above to
determine if the damper blades are correct for the
conditions.
a. Determine mode. The EF-B unit should be in
cooling if the supply air temperature is below
the set point. It is in heating if the supply air
temperature is above both the room
temperature and the set point.
b. For room temperatures more than 2ºF/1.2ºC
from set point, damper blades should be
moving to the position as shown in the Fig. 3
Troubleshooting.
Cooling
Heating
Room Temp vs
Set Point
+2ºF /
1.2ºC
-2ºF /
1.2ºC
+2ºF /
1.2ºC
-2ºF /
1.2ºC
Damper Blade
Position
Open
Closed
Closed
Open
Fig. 3 Troubleshooting
Notes:
i. Room temperature more than ±2ºF/1.2ºC
from set point has been selected as a general
rule of thumb for trouble shooting to avoid
more complicated control algorithms within
that band. Control is intended to be tighter
but will depend on system conditions.
ii. If any of the set points are changed to
achieve full open or full closed conditions,
wait 5 to 10 minutes to make sure the room
and system have stabilized.
Small Ruler

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BACNET™ MOTORIZED VAV DIFFUSER
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TROUBLE SHOOTING
FIG. 4 THERMISTORS
EF-B Electrical
15. A green LED near the 24VAC Supply Power terminals should be lit indicating
good supply voltage (see Fig. 5 Wiring Diagram).
16. Check the fuse near the 24VAC Supply Power terminals (see Fig. 5 Wiring
Diagram).
17. Reset the EF-B using the network command ReinitalizeDevice. If
ReinitalizeDevice is unavailable from the preferred BACnet software then cycle
the power by unplugging the 24VAC Supply Power terminals and then reconnecting them.
18. Use a computer on the network running the preferred BACnet software to check the Status_Flags on each of the following
Objects: analog_input_0 (oRmTemp), analog_input_1 (oSATempt), and analog_input_3 (oFlowTemp).
a. If Status_Flag ‘overridden’ then check analog_value_26 (iRmTemp), analog_value_27 (iSATemp), and analog_value_28
(iFlowRate) respectively.
b. If Stuats_Flag ‘in_alarm’, ‘fault’, or ‘out_of_service’ then check the sensors.
i. Remove the controller cover.
ii. Remove the wires to each sensor (ROOM TEMP,
DUCT TEMP, and FLOW1-4 TEMP) from the
terminals (see Fig. 5 Wiring Diagram).
iii. Measure the resistance between each wire
and the terminal marked common (see Fig. 4
Thermostors).
iv. If the resistance is correct per Fig. 4 Thermistors,
reinstall the wire making sure that it makes contact
with the terminal.
v. If the resistance is outside the range, check the
common terminal connections.
vi. If all common wires are in contact with the
terminals and the resistance is still outside the
range, contact Acutherm.
Motor Control Board (MCB)
19. Check power
a. Red LED on when end switch first engaged or flashing when motor moving
b. 35.5VDC on terminals + - PWM (occasional flicker of voltage when control signal is passed to MCB)
20. Check dip switch setting
a. EF-B-M-6 – ON OFF OFF OFF
b. EF-B-M-8 – OFF ON OFF OFF
c. EF-B-M-10 – ON ON OFF OFF
d. EF-B-M-12 – OFF OFF ON OFF
21. Check motor
a. When looking in neck of diffuser
i. Flash short-long = clockwise
ii. Flash long-short = counterclockwise
iii. EF-B-M is counterclockwise to close
b. Check motor winding resistance
i. Unplug 6-pos connector on MCB
ii. 19Ω between 1A and 2A
iii. 19Ω between 1B and 2B
iv. No connectivity between 1 and 2
22. Check switch
a. Switch on 0VDC between + - SW b. Switch off (open) 3VDC between + - SW
Temperature Resistance
50ºF / 10ºC 2000 Ω
77ºF / 25ºC 1000 Ω
95ºF / 35ºC 650 Ω

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BACNET™ MOTORIZED VAV DIFFUSER
Maintenance
The moving parts of the EF-B diffuser have no maintenance or lubrication requirements. We are often asked to recommend
periodic maintenance procedures and a spare parts stock. Recommended maintenance is to clean the outer surfaces of the
Therma-Fuser diffuser - nothing else. We do not recommend stocking any spare parts. Our customers also confirm that stocking
is unnecessary.
Controlling the System
References:
• System Design section of EF-B Brochure (Form 091.101).
• Chapters 2.2, 3.1 and 3.2, pg. 6, 7 and 8, Designing
Modular VAV Systems (Form 5.2).
• Air Handling and Fan Coil Units Subzoned with Therma-
Fuser VAV Diffusers (Form 6.7).
• Dx Equipment Zoned with Therma-Fuser VAV Diffusers
(Form 6.5).
Supply Air Temperature
The sources of cooling and heating are controlled from supply air temperature. As with all VAV systems the goals are to achieve a
constant supply air temperature (may be reset to another constant supply air temperature) and to limit the supply air temperature.
Limits for supply air temperature should be between 50˚F/10˚C and 68˚F/20˚C when cooling and between 80˚F/26.5˚C and
120˚F/49˚C when heating. The heating temperature limit should be as low as possible. These objectives are best achieved by
modulating chilled water valves, hot water valves and other variable equipment from supply air temperature. On/off equipment
such as DX compressors and electric heat are cycled from supply air temperature. Use a discharge air sensor for the supply air
temperature signal.
Mode change between heating, recirculation and cooling is controlled from room temperature. Object analog_input_0 (oRmTemp)
from the EF-B Therma- Fuser diffuser may be used for mode change. A “majority rules” approach is recommended.
Static Air Pressure
As with all VAV systems, the fan must run continuously during the occupied hours. Goals of static pressure control are to provide
enough static pressure to obtain the required air volume especially at the diffuser farthest from the fan, to limit static pressure at
both full flow and turndown, to avoid diffuser noise and to provide pressure independence or consistent operation as the system
flow changes. These objectives can be achieved with the usual methods of automatic static pressure control: bypass dampers,
zone dampers, and fan speed control (variable frequency drives, inlet dampers, etc.). Locate the static pressure sensor as far
down the duct as possible - at least 2/3 down the duct from the first takeoff.
MAINTENANCE & CONTROLLING THE SYSTEM

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8
BACNET™ MOTORIZED VAV DIFFUSER
BACNET™ MOTORIZED VAV DIFFUSER - Manual | acutherm.com
Acutherm warrants that its Model EF-B diffuser, exclusive of any options and accessories (whether factory or field installed) shall
be free from defective material or workmanship for a period of two (2) years from the date of shipment and agrees to repair or
replace, at its option, any parts that fail during said two (2) year period due to any such defects which would not have occurred
had reasonable care and proper usage and all parts and controls remain unaltered. Acutherm makes NO WARRANTY OF
MERCHANTABILITY OF PRODUCTS OR OF THEIR FITNESS FOR ANY PURPOSE OR ANY OTHER EXPRESS OR
IMPLIED WARRANTY WHICH EXTENDS BEYOND THE LIMITED WARRANTY ABOVE. ACUTHERM’S LIABILITY FOR
ANY AND ALL LOSSES AND DAMAGES RESULTING FROM DEFECTS SHALL IN NO EVENT EXCEED THE COST OF
REPAIR OR REPLACEMENT OF PARTS FOUND DEFECTIVE UPON EXAMINATION BY ACUTHERM. IN NO EVENT
SHALL ACUTHERM BE LIABLE FOR INCIDENTAL, INDIRECT OR CONSEQUENTIONAL DAMAGES OR DAMAGES FOR
INJURY TO PERSONS OR PROPERTY. Acutherm shall not be responsible for freight to or from its plant in connection with the
inspection, repair or replacement of parts under the terms of this limited warranty nor for cost of removal or installation.
Network Wiring Notes from ASHRAE 135
The BACnet MS/TP protocol uses EIA-485 (RS485) as its physical layer. EAI-485 is a three conductor network. All network wiring
should be to the ASHRAE Standard 135 (summarized below) with the twisted pair used for ‘+’ and ‘-‘, maintain polarity, and use
the drain wire as the third conductor for the ‘COM’.
ASHRAE Standard 135 9.2.1 Media for network wiring:
• Topology: daisy chain, bus
• Wire: shielded twisted pair (with drain), 18 AWG 0.82mm2conductor area
• Impedance: 100-130Ω
• Capacitance, distributed: between conductors <100pF/m (30pF/ft) and between conductors and shield <200pF/m (60pF/ft)
• Max length: 1200m (4000ft) per segment
• Use terminating 120Ω ¼W 5% resistors at each end
TWO YEAR WARRANTY
EF-B-M BACnet MOTORIZED VAV DIFFUSER FORM 091.205 REV 1403
INSTALLATION OPERATION AND MAINTENANCE
(Supersedes nothing)
ACUTHERM HEADQUARTERS 1766 Sabre Street Hayward, CA 94545 USA Tel [phone] Fax [phone] www.acutherm.com
Fig. 7 Wiring Diagram
HTR-HTR+COMHTR
TEM P
DUCT
TEM P
COMR OOM
TEM P
FLO W4
TEM P
COMFLO W3
TEM P
FLO W2
TEM P
COMFLO W1
TEM P
1
OP TN 1
OP TN 2
OP TN 3
TERM
FUSE
500 mA
CAUT ION: DISCONNECT POWER
BEFOREREPLACING FUSE
AC UTHER M, L LC
E-BOARD BACnet
ASSY-508 -2092-REVC
24VAC
(POWER IN)
(+) (-) COM
(BACnet)
+5v (+) (-) COM
(SENS OR N ET)
1W CO M
(1-WIR E)
AI P COM AOP
(0-10V) (0-10 V)
BACnet Network
24VAC Supply
Power
Dip Switches 1-64
set MAC address
Dip Switch AUTOM
must be offto allow
MAC address to be
set with dip switches
1-64
Factory Wiring
Fuse
500mA
Power
LED
Button to re-send
I AM message
Dip Switch TERM
enables a 120 end
of line resistor
1 2 3 4 1 2 3 4 1 2 3 4
ONOFF
ETHER NET
LED to confirm
button press
SWIT CH
/LE D
+ - COM
Connection
2
4
8
16
32
64
AUTOM
MAC ADDRESS
24VA C
AC UTHER M, L LC
MOTORIZED DFSR CTL BD
808 -24 74 -REVC
+ BMS - +5V N ET+ NET -GND
1 2 3 4
ROO M G RD D UCT
1A 2A 1B 2B - SW ++ P WM -
ON
Factory Wiring
MOTOR CONTROL BOARD
BACnet CONTROL BOARD
EF-B-M BACnet MOTORIZED VAV DIFFUSER FORM 091.205 REV 1403
INSTALLATION OPERATION AND MAINTENANCE
(Supersedes nothing)
ACUTHERM HEADQUARTERS 1766 Sabre Street Hayward, CA 94545 USA Tel [phone] Fax [phone] www.acutherm.com
Fig. 7 Wiring Diagram
HTR-HTR+COMHTR
TEM P
DUCT
TEM P
COMR OOM
TEM P
FLO W4
TEM P
COMFLO W3
TEM P
FLO W2
TEM P
COMFLO W1
TEM P
1
OP TN 1
OP TN 2
OP TN 3
TERM
FUSE
500 mA
CAUT ION: DISCONNECT POWER
BEFOREREPLACING FUSE
AC UTHER M, L LC
E-BOARD BACnet
ASSY-508 -2092-REVC
24VAC
(POWER IN)
(+) (-) COM
(BACnet)
+5v (+) (-) COM
(SENS OR N ET)
1W CO M
(1-WIR E)
AI P COM AOP
(0-10V) (0-10 V)
BACnet Network
24VAC Supply
Power
Dip Switches 1-64
set MAC address
Dip Switch AUTOM
must be offto allow
MAC address to be
set with dip switches
1-64
Factory Wiring
Fuse
500mA
Power
LED
Button to re-send
I AM message
Dip Switch TERM
enables a 120 end
of line resistor
1 2 3 4 1 2 3 4 1 2 3 4
ONOFF
ETHER NET
LED to confirm
button press
SWIT CH
/LE D
+ - COM
Connection
2
4
8
16
32
64
AUTOM
MAC ADDRESS
24VA C
AC UTHER M, L LC
MOTORIZED DFSR CTL BD
808 -24 74 -REVC
+ BMS - +5V N ET+ NET -GND
1 2 3 4
ROO M G RD D UCT
1A 2A 1B 2B - SW ++ P WM -
ON
Factory Wiring
MOTOR CONTROL BOARD
BACnet CONTROL BOARD
EF-B-M BACnet MOTORIZED VAV DIFFUSER FORM 091.205 REV 1403
INSTALLATION OPERATION AND MAINTENANCE
(Supersedes nothing)
ACUTHERM HEADQUARTERS 1766 Sabre Street Hayward, CA 94545 USA Tel [phone] Fax [phone] www.acutherm.com
Fig. 7 Wiring Diagram
HTR-HTR+COMHTR
TEM P
DUCT
TEM P
COMR OOM
TEM P
FLO W4
TEM P
COMFLO W3
TEM P
FLO W2
TEM P
COMFLO W1
TEM P
1
OP TN 1
OP TN 2
OP TN 3
TERM
FUSE
500 mA
CAUT ION: DISCONNECT POWER
BEFOREREPLACING FUSE
AC UTHER M, L LC
E-BOARD BACnet
ASSY-508 -2092-REVC
24VAC
(POWER IN)
(+) (-) COM
(BACnet)
+5v (+) (-) COM
(SENS OR N ET)
1W CO M
(1-WIR E)
AI P COM AOP
(0-10V) (0-10 V)
BACnet Network
24VAC Supply
Power
Dip Switches 1-64
set MAC address
Dip Switch AUTOM
must be offto allow
MAC address to be
set with dip switches
1-64
Factory Wiring
Fuse
500mA
Power
LED
Button to re-send
I AM message
Dip Switch TERM
enables a 120 end
of line resistor
1 2 3 4 1 2 3 4 1 2 3 4
ONOFF
ETHER NET
LED to confirm
button press
SWIT CH
/LE D
+ - COM
Connection
2
4
8
16
32
64
AUTOM
MAC ADDRESS
24VA C
AC UTHER M, L LC
MOTORIZED DFSR CTL BD
808 -24 74 -REVC
+ BMS - +5V N ET+ NET -GND
1 2 3 4
ROO M G RD D UCT
1A 2A 1B 2B - SW ++ P WM -
ON
Factory Wiring
MOTOR CONTROL BOARD
BACnet CONTROL BOARD
EF-B-M BACnet MOTORIZED VAV DIFFUSER FORM 091.205 REV 1403
INSTALLATION OPERATION AND MAINTENANCE
(Supersedes nothing)
ACUTHERM HEADQUARTERS 1766 Sabre Street Hayward, CA 94545 USA Tel [phone] Fax [phone] www.acutherm.com
Fig. 7 Wiring Diagram
HTR-HTR+COMHTR
TEM P
DUCT
TEM P
COMR OOM
TEM P
FLO W4
TEM P
COMFLO W3
TEM P
FLO W2
TEM P
COMFLO W1
TEM P
1
OP TN 1
OP TN 2
OP TN 3
TERM
FUSE
500 mA
CAUT ION: DISCONNECT POWER
BEFOREREPLACING FUSE
AC UTHER M, L LC
E-BOARD BACnet
ASSY-508 -2092-REVC
24VAC
(POWER IN)
(+) (-) COM
(BACnet)
+5v (+) (-) COM
(SENS OR N ET)
1W CO M
(1-WIR E)
AI P COM AOP
(0-10V) (0-10 V)
BACnet Network
24VAC Supply
Power
Dip Switches 1-64
set MAC address
Dip Switch AUTOM
must be offto allow
MAC address to be
set with dip switches
1-64
Factory Wiring
Fuse
500mA
Power
LED
Button to re-send
I AM message
Dip Switch TERM
enables a 120 end
of line resistor
1 2 3 4 1 2 3 4 1 2 3 4
ONOFF
ETHER NET
LED to confirm
button press
SWIT CH
/LE D
+ - COM
Connection
2
4
8
16
32
64
AUTOM
MAC ADDRESS
24VA C
AC UTHER M, L LC
MOTORIZED DFSR CTL BD
808 -24 74 -REVC
+ BMS - +5V N ET+ NET -GND
1 2 3 4
ROO M G RD D UCT
1A 2A 1B 2B - SW ++ P WM -
ON
Factory Wiring
MOTOR CONTROL BOARD
BACnet CONTROL BOARD
FIG. 2 WIRING DIAGRAM

9
NOTES
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BACNET™ MOTORIZED VAV DIFFUSER

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