Antec controls VENTURI FX User manual

VENTURI FX
MANUAL v106

VFX - MANUAL
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TABLE OF CONTENTS
INTRODUCTION ...............................................................................................................................................................................1
General..........................................................................................................................................................................................1
Safety Precautions ........................................................................................................................................................................1
Product Overview .........................................................................................................................................................................2
Technical Specifications ................................................................................................................................................................2
Airflow Ranges..............................................................................................................................................................................2
GETTING STARTED WITH THE VENTURI FX (VFX)..........................................................................................................................3
Receiving Inspection .....................................................................................................................................................................3
In the Box......................................................................................................................................................................................3
Construction Options ....................................................................................................................................................................4
INSTALLATION & MOUNTING INSTRUCTIONS..............................................................................................................................6
Installing the Venturi FX (VFX) Valve .............................................................................................................................................6
VALVE ACCESSORIES .....................................................................................................................................................................8
Hot Water Coils (VVHWC).............................................................................................................................................................8
Electric Coils (VVEC)....................................................................................................................................................................10
Silencer (VVSIL)...........................................................................................................................................................................12
Valve Companion Connections (VCT)..........................................................................................................................................13
Valve Installation Tape (VIT) ........................................................................................................................................................16
Valve Actuator .............................................................................................................................................................................17
BALANCING ...................................................................................................................................................................................18
Variable Volume VFX ...................................................................................................................................................................18
TROUBLESHOOTING.....................................................................................................................................................................19
Venturi FX Troubleshooting.........................................................................................................................................................19
Electric Coil Troubleshooting.......................................................................................................................................................19
Replacement Parts......................................................................................................................................................................20
Technical Support........................................................................................................................................................................20

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INTRODUCTION
General
In this manual, you will find information regarding:
•Venturi FX (VFX) specifications
•How to install the VFX with Constant Volume, Variable
Volume, and Two Position Switch
•Detailed description of all options available for each setup
Safety Precautions
1. Installation work and electrical wiring must be done by
qualified person(s) in accordance with all applicable
codes and standards, including fire-rated construction.
2. When cutting or drilling into wall or ceiling, do not
damage electrical wiring and other hidden utilities.
3. Use this unit only in the manner intended by the
manufacturer.
4. Before servicing or cleaning unit, switch power off at
service panel and lock service panel to prevent power
from being switched on accidentally.
5. Protect flammable materials nearby when brazing, use
flame and heat protection barriers where needed.
Always have a fire extinguisher ready.
6. The manufacturer assumes no responsibility for
personal injury or property damage resulting from
improper handling, installation, service or operation of
the product.
Caution to Contractors
VFX Valves are not intended for use as temporary heat or
ventilation sources during building construction. The units
are not designed nor equipped to operate in a dusty
construction environment. Internal parts can become coated
in construction dust, resulting in loss of calibration and
excess wear on the product which in turn can contribute to
reduced life.
This mark indicates an important point for
the proper function of the VFX and any of its
accessories. Pay close attention to all
caution points throughout this manual.
CAUTION
For support and in-depth
training on this product and
other associated system
components, please
contact your local Antec
Controls Representative.
For more information visit
www.AntecControls.com

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Product Overview
The Antec Controls Venturi FX Valve (VFX) is designed specifically for room pressure control in healthcare and laboratory
applications. Paired with the maintenance-free, high accuracy Antec Controls Pressure Transducer (PTX) or the Pace™ Critical
Space Controller (PACE) and an actuator, the VFX achieves precise airflow measurement and control for critical environments.
Technical Specifications
Environmental
(Operating)
50°F to 122°F (10°C to 50°C), 5% to 95% R.H. (non-condensing)
Environmental (Storage)
-22°F to 122°F (-30°C to 50°C), 0% to 95% R.H. (non-condensing)
Valve Body
14 Ga Aluminum
Damper Assembly
Uncoated: Two 24 Ga galvanized steel plates and a Teflon gasket mounted on a zinc plated
steel shaft.
Coated: Two 22 Ga 316 stainless stee plates and a Teflon gasket mounted on a 316 stainless
steel shaft.
Pressure Sensor
316 Stainless Steel Tubes
Airflow Ranges
Unit Size
Airflow Range
Kfactor
Minimum CFM (L/s)
Maximum CFM (L/s)
108
80 (38)
800 (378)
600
110
120 (57)
1300 (614)
975
112
180 (85)
1800 (850)
1400
114
250 (118)
2500 (1180)
1985
212
360 (170)
3600 (1700)
2800
214
500 (236)
5000 (2360)
4000
Flow Calculation
The VFX requires a 0 to 2 in.w.c. transducer to measure flow. Using the differential pressure reading (dP), the flow is calculated
using the following equation:
= ∗√
NOTES:
1. Factory calibrated controls must be selected within the above flow range limits. When setting the flow, the value must be
greater than the minimum setting and within the range limits. Selection of air flow below the listed values is not
recommended. Stability and accuracy may not be acceptable at lower than recommended air flow limits.
2. Please refer to the VFX Product Submittals for all dimensional data.

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GETTING STARTED WITH THE VENTURI FX (VFX)
Receiving Inspection
After unpacking the assembly, check carefully for shipping damage. If any damage is found, report it immediately to the
delivering carrier. Damage may result from improper handling.
In the Box
For each of the available controllers the order includes the following components outlined in this section.
Venturi FX (VFX)
The VFX ships with several different components. The components are outlined in this
section for a single VFX.
Component
Quantity
Description
Valve Body
1, 2 or 3
VFX
NOTE: Dual and Triple VAV valves will be shipped
as a ganged assembly.
Green Pressure
Tubing
1
The low-pressure tubing comes with a length of
tubing factory connected to the controller.
Red Pressure
Tubing
1
The low-pressure tubing comes with a length of
tubing factory connected to the controller.
Actuator
1, 2 or 3
The actuator is factory mounted on the mounting
bracket and shaft.
NOTE: Dual and Triple valves will be shipped with 2
and 3 actuators, respectively.
Controller
1
Single controller.
Do not tamper with the linkage assembly as
the valve is shipped factory calibrated.
Never carry or lift the valve by the damper
shafter, flow measuring stations or the
control enclosure.
CAUTION

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Construction Options
Below is an outline of some of the key options that are available when selecting and ordering Venturi FX (VFX). These options
will affect its available flow range, how the valve is installed and under what system conditions it must operate.
See the VFX Product Submittal on AntecControls.com for Specifications and Dimensions of each option shown below.
Valve Size
The VFX is available in the following size options. The size selected below will be a factor in determining the airflow range of
the valve.
8 inches
Model:
Features:
VFX-108
•Available in Single construction only
10 inches
Model:
Features:
VFX-110, VFX-210
•Available in Single and Dual construction
•Dual construction is provided in a welded ganged unit and no additional field assembly is required
12 inches
Model:
Features:
VFX-112, VFX-212
•Available in Single and Dual construction
•Dual construction is provided in a welded ganged unit and no additional field assembly is required
14 inches
Model:
Features:
VFX-114, VFX-214
•Available in Single and Dual construction
•Dual construction is provided in a welded ganged unit and no additional field assembly is required
Connection Type
The connection type of the valve will determine how the valve is installed in the ductwork. See the Installation Instructions
section for more detail on the installation process.
Slip
Model:
Features:
VV-SL
•VFX does not contain any mounting holes
•Single sizes are designed to slip into nominal sized round ductwork
•Dual, Triple and Quad sizes are designed to slip over rectangular ductwork
NOTE: See the Installing the Venturi FX for detailed installation instructions.
Flanged
Model:
Features:
VV-FL
•VFX comes with pre-welded mounting flange
NOTES:
•See the Installing the Venturi FX for detailed installation instructions.
•See the VV Product Submittal for hole pattern and dimensions.

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Coating
The Venturi FX is available in four different protective coating options depending on the application.
Aluminum
Model:
Features:
VFX-AL
Aluminum valve body with Stainless Steel (SS) internal hardware
NOTE: Can be mounted using sheet metal screws.
Phenolic – Class 1
Model:
Features:
VFX-P1
Phenolic coated valve body with Stainless Steel (SS) internal
hardware
Scratches and holes can compromise the coating
NOTE: Do not use sheet metal screws in valve body.

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INSTALLATION & MOUNTING INSTRUCTIONS
Installing the Venturi FX (VFX) Valve
The instructions below detail general installation of a VFX without the use of any valve accessories. When using accessories
with the VFX, please see the appropriate installation detailed for the accessory being used in the Valve Accessories section.
Before Installation
General Installation Notes
1. Ductwork to be supported within eighteen inches (18”) of the Venturi
FX unless otherwise specified.
2. Access doors are not required.
3. Leave eight inches (8”) of free space in all directions of the controls
enclosure to facilitate future access to the controls.
4. During operation, the blade damper of the VFX may extend past the
discharge of the valve. Ensure that a minimum of three inches (3”) of
duct space is clear of any obstacles from the valve discharge.
5. Maximum screw lengths when installing the VFX are seen is the table
below. If this screw length is exceeded, it may impede the rotation of
the damper shaft.
NOTE: Maximum screw length is based on screw distance of ½ in.
from end of the VFX slip connection.
Valve Size
Maximum Screw Length
108
1/2 in.
110
3/8 in.
112
3/8 in.
114
3/8 in.
Enclosure Orientation
Venturi FX controls enclosures may be rotated 360 degrees around the ductwork.
1. Visually inspect the valve for damage
a. Damage to the flow measuring stations in the valve can be
detrimental to performance
b. Damage to the coating on fume hood valves can lead to corrosion
2. Inspect the tamper proof paint on the actuator to ensure it has not been
removed.
3. Ensure the Specification label for the valve matches the intended
installation location.
Enclosure Orientation
In fume hood applications, or in conditions that may cause condensation inside the
ductwork, the enclosure should not be mounted within +/- 90 degrees from straight down.
Do not screw into Phenolic or Kynar
coated valve bodies. Screws will
compromise its resistance to corrosion.
Warranty will be void if screws are
used, excluding mounting slip
connection multi-body valves.
CAUTION

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Slip-Connection Venturi FX (VFX) Mounting Instructions
The instructions below are detailed for Aluminum VFXs only. Do not use screws for Phenolic coated valves.
Flange-Connection Venturi FX (VFX) Mounting Instructions
STEP 1
Mount the VFX by slipping both the inlet and the discharge one inch (1”) into the
appropriately sized ductwork.
STEP 2
Fasten the VFX to the ductwork using six (6) sheet metal screws per slip connection.
STEP 3
Seal the ductwork using duct sealer.
STEP 1
Align the duct flange holes with the VFX flange holes and fasten using a bolt, lock washer
and nut. Fasten every hole to reduce airflow leakage.
NOTE: It is recommended to use a duct sealant or gasket between the valve flange and the
ductwork flange.
Instructions above are for slip valves without
drawband clamps. For information on
installing slip valves with drawband clamps,
please see the Drawband Clamps.
CAUTION
Instructions above are for flanged valves
without companion flanges. For information
on installing flanged valves with companion
flanges, please see the Companion Flanges.
CAUTION

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VALVE ACCESSORIES
Venturi FX (VFX) can function with a variety of different products to control air temperature, decrease noise and improve ease of
installation.
Valve Accessories and Optional Products provided by
Antec Controls include:
1. Hot Water Coils (VVHWC)
2. Electric Coils (VVEC)
3. Silencer (VVSIL)
4. Valve Companion Connections (VCT)
5. Valve Installation Tape (VIT)
6. Valve Actuator
Hot Water Coils (VVHWC)
Hot Water Coils (VVHWC) are devices installed with VFX that control room environment by heating air moving through the
valve. The VVHWC is designed to optimize heat transfer and access doors are available for upstream installation for convenient
maintenance.
Overview
See the VVHWC Product Submittal on AntecControls.com for specifications and dimensions of the options below.
Options
Standard Capacity Hot Water Coil
Model:
Features:
VVHWC-SC
•22 Gauge zinc-coated steel casing
•One to four row construction
•Aluminum fins spaced at 10 fins per inch
High Capacity Hot Water Coil
Model:
Features:
VVHWC-HC
•22 Gauge zinc-coated steel casing
•One or two row construction
•Aluminum fins spaced at 12 fins per inch
Oversized Standard Capacity Hot Water Coil
Model:
Features:
VVHWC-OSC
•22 Gauge zinc-coated steel casing
•One to four row construction
•Aluminum fins spaced at 10 fins per inch
Oversized High Capacity Hot Water Coil
Model:
Features:
VVHWC-OHC
•22 Gauge zinc-coated steel casing
•One or two row construction
•Aluminum fins spaced at 12 fins per inch
Different types of valve accessories can be
used with the VFX. When using
accessories by Others, ensure the
dimensions and installation are compatible
with the Antec Controls VFX.
CAUTION

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Installation
STEP 1
Hot Water Coils are only available in supply orientation and should always be located down
stream of the supply Venturi FX.
STEP 2
For single VVHWCs, position the bead connection so that it faces the airflow.
For multibody VVHWCs, position the slip connection so that it faces the airflow.
NOTE: Both single and multibody valves have slip and drive connections that will face down
stream of the airflow.
STEP 3
Before installing the plumbing connections for the VVHWC, check the coil hand designation
and ensure that it matches the system.
Generally, coils are plumbed with the supply connection located on the bottom of the leaving
air-side and the return connection at the top of the entering air-side of the coil to provide
counter flow heat exchange and positive coil drainage.
For one or two row water coils both parallel and counterflow orientations are acceptable,
however, for three or four row water coils only counterflow orientation is acceptable.
If a universal coil is supplied, cap off the two unused connections.
The coils inlet for the heating medium is provided with copper connectors with the
customers requested ends. If pipe fittings have been furnished, use a back-up wrench to
install or uninstall the coil.
NOTE: The configuration of the coil connection varies with size, type and circuitry of coil.
STEP 4
Maintain proper clearance (minimum 1.5”) between the coil and other structures such as the
fan, filter racks, transition areas, etc.
STEP 5
Mount the coil firmly and level to ensure it’s secure in its location and it’s able to drain.
Use the support method prescribed for the duct work in the job specifications.
Coils with intermediate headers can be pitched 1/8” per foot of coil finned length towards
the coils header/connection end.
The system must be adequately vented to operate effectively.
STEP 6
All field piping must be self-supporting. System piping should be flexible enough to allow for
thermal expansion and contraction of the coil.
STEP 7
If freezing is likely, blow compressed air into the coil. This will ensure that it has been
thoroughly drained.
Anti-freeze protection should be added if needed.

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Electric Coils (VVEC)
Electric Coils (VVEC) are devices installed with Venturi FX that control room environment by heating the air moving through the
valve. The VVEC operates using standard building electrical power and is designed to optimize heat transfer.
Overview
See the VVEC Product Submittal on AntecControls.com for specifications and dimensions of the options below.
Options
Electric Coils
Model:
Features:
VVEC
•Automatic reset thermal cut-out
•Manual reset thermal cut-out
•Air flow switch
•20 Gauge galvanized steel, mechanically sealed, leak
resistant construction
•SCR Controls – 2 to 10 VDC
Before Installation
1. Check for shipping damage to heater assembly including, but not limited to, ceramic coil clips and wire damage. If damage is
found, do not power up heater, file claim with carrier and/or replace heater.
2. Check electrical specification label to ensure proper voltage/current ratings.
3. Before wiring, review and adhere to all local building codes, ordinances and the National Electric Code, pertaining to
installation of the equipment.
4. Determine if the unit is field flippable between left and right handling.
5. If mercury contactors are included, ensure the arrow on the label is pointed upward.
NOTES:
1. To maintain ETL certification, electric coils must only be installed as they have been marked on the installation label provided
on the door of the electric coil control panel. (Installation Label PIC)
2. A minimum static pressure of 0.20 in.w.c is required for stable operation with electric heater controls.
When installing, do not handle the unit by
the inlet velocity sensor. Ensure any
packing material is removed from the inside
of the unit.
CAUTION

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Electrical Installation
1. Review Electrical Wiring diagram included with heater (typically glued to inside of electrical enclosure door).
2. Ensure circuit powering the heater has proper capacity. Follow local building codes.
3. The electric duct heater must have an uninterrupted or unbroken electrical ground to minimize the chance of injury should an
electrical fault occur. This may consist of an electrical wire or approved conduit when installed in accordance with existing
electrical codes.
4. Review and inspect safety devices.
a. Automatic Reset – trips if air surrounding the coils is too hot (~130F); will reset itself after cooling (~115F)
b. Manual Reset – trips if air surrounding coils increases rapidly (~150F); to reset press the red tab towards the reset switch
contacting the protruding metal tab on the relay
i. If electric coil does not have a red tab, press down the protruding metal tab on the relay by hand
c. Airflow Switch – trips ON when valve pressure differential is detected
i. Ensure airflow switch probe points into the air stream
ii. Note, the airflow switch must be mounted in a vertical plane; if this is not followed, the switch will always output a
constant ON or OFF regardless of airflow
Mechanical Installation
STEP 1
Electric coils are only available in supply orientation and should always be located down
stream of the supply Venturi FX (VFX).
STEP 2
Use the support method prescribed for the duct work in the job specifications.
STEP 3
Install the pressure sensor pick-up tube up-stream of the VFX valve.
Disconnect all incoming power before any
electrical installation or service is performed
on the unit(s).
CAUTION

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Silencer (VVSIL)
The Silencer (VVSIL) is a highly engineered 14-inch silencer specifically designed for the full spectrum attenuation of sounds
produced by Venturi FXs (VFX). The packless design provides minimal disturbance in the airflow resulting in low pressure drops
across the silencer.
Overview
See the VVSIL Product Submittal on AntecControls.com for specifications and dimensions.
Options
Installation
VV Silencer
Model:
Features:
VVSIL
•Factory mounted transitions
•Slip connection
•Made to fit Single, Dual, Triple, or Quad valves
•22ga Galvanized Steel Construction or 24ga 316 Stainless Steel Construction
STEP 1
Position silencer before the inlet of the VFX when the VFX is operating as an exhaust valve.
Position silencer on the discharge of the VFX when the VFX is operating as a supply valve.
STEP 2
It is recommended that the silencer be installed prior to installing the VFX.
STEP 3
Use the support method prescribed for the duct work in the job specifications.
STEP 4
Mount the silencer to the duct. The slip connection should overlap a minimum of one inch
(1”) to ensure a proper fit.
STEP 5
Mount the VFX by slipping the appropriate end into the available duct work and the other end
into the free slip connection of the silencer. Each slip connection should overlap a minimum
of one inch (1”) to ensure a proper fit.
STEP 6
Fasten all connections using six (6) sheet metal screws per slip connection.
STEP 7
Seal slip connections using duct sealer.

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Valve Companion Connections (VCT)
Valve Companion Connections (VCT) come in two different types: drawband clamps and companion flanges.
Drawband clamps are designed as a connection method specifically for slip Venturi FXs. Drawband clamps are an alternative to
directly fastening the valve to the ductwork. The drawband clamp provides uniform compression, connecting spiral or plain
ductwork to a valve, ensuring that the valve is properly supported. Drawband clamps allow for quick installation or removal of
the Venturi FX while minimizing damage from metal screws.
Companion flanges are available for single body valves. Companion flanges are to be slid onto duct with a 1.5-inch overlap and
mechanically fastened to the valve flange.
Overview
See the VCT Product Submittal on AntecControls.com for specifications and dimensions.
Options
Slip Connection Venturi FX with Drawband Clamps
Model:
Features:
VCT - DBC
•Galvanized steel band and brackets
•UL 94 Elastomeric foam gasket
•Zinc plated flanged hex bolts with nylock nuts
•25ga galvanized steel or 24ga 304 stainless steel construction
Flange Connection Venturi FX with Companion Flange
Model:
Features:
VCT - CFL
•Aluminum or 316 Stainless Steel (SS) construction

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Slip-Connection Venturi FX (VFX) with Drawband Clamps Installation
STEP 1
Slide drawband clamps completely onto the inlet and discharge ductwork.
STEP 2
Mount the VFX by slipping both the inlet and the discharge one inch (1”) into the
appropriately sized ductwork.
STEP 3
Apply appropriate tape to seal valve to duct work if required. Two full wraps around the
connection are recommended.
NOTES:
1. For non-corrosive applications duct tape can be used.
2. For corrosive applications VIT must be used.
STEP 4
Slide the drawband clamps onto the valve ensuring that at least one and a half inches (1.5”)
of the drawband clamps are in contact with the valve body.
STEP 5
Tighten both nuts to 15 in⋅lbs to ensure that the drawband clamp is securely fastened to the
valve body and duct work. Neither the valve nor the band clamp should shift after fastening.
NOTE: Over-torqueing the drawband clamp may cause improper connection. Recommended
torque is listed on the drawband clamp label (typically the first torque setting on an electrical
drill).
Ensure location of bead is correct. For size 8, 10 and 12 valves, the bead should
be on the valve. For size 14 valves, the bead should be on the ductwork. Refer
to torque rating on the drawband clamp label.
Do not screw through the drawband clamp into the VFX body.
CAUTION

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Flange-Connection Venturi FX with Companion Flanges Installation
STEP 1
Slide companion flanges completely onto the inlet and discharge ductwork with the flanged
end of the companion flanges toward the free space.
STEP 2
Align hole pattern to match opposing companion flange.
STEP 3a
For Aluminum Companion Flanges, fasten each companion flange with six (6) sheet metal
screws. Apply duct sealant to seal the ductwork.
STEP 3a
For Stainless Steel Companion Flanges, continuously weld the companion flange to the duct
to ensure zero leakage.
STEP 4
Align the duct flange holes with the venturi flange holes and fasten using a bolt, lock washer
and nut. Fasten every hole to reduce airflow leakage.
NOTE: It is recommended to use a duct sealant or gasket between the valve flange and the
ductwork flange.

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Valve Installation Tape (VIT)
Valve Installation Tape (VIT) is used during installation of the Venturi FX in corrosive applications and is wrapped around the
valve and ductwork connection to ensure an airtight seal.
Overview
See the VIT Product Submittal on AntecControls.com for specifications.
Options
Valve Installation Tape
Model:
Features:
VIT
•PTFE adhesive tape
•108 ft. in length
•2.0 in. in width

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Valve Actuator
Valve actuators are wired into the valve controller and are attached to the linkage bars of the valve. The actuator controls the
position of the blade damper inside of the Venturi FX which controls the amount of air that flows through the valve. Valve
actuators come in two main options: Standard Speed and High Speed.
Overview
See the Valve Actuator Product Submittal on AntecControls.com for list of all available models with their associated
specifications and dimensions.
Options
Standard Speed Actuator
Model:
Features:
SSA
•Running time ranging between 75 to 95 seconds
•External push button manual override
•Reversible direction of rotation with built-in switch
•2-10 VDC or 2P
High Speed Actuator
Model:
Features:
HSA
•Running time ranging between 2.5 to 4 seconds
•External push button manual override
•Reversible direction of rotation with built-in switch
•2-10 VDC or 2P

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BALANCING
The balancing process is required in the field to ensure that the valves are providing the necessary flow into and out of the
pressure-controlled space. The process involves measuring the airflow through the valve in the field, using third party calibrated
equipment and comparing it to the calibrated position feedback from the Venturi FX (VFX).
Variable Volume VFX
Adjustments to the flow reading can be made by adjusting the Kfactor.
NOTE: When using PACE or CAVA controllers from Antec Controls, please refer to the appropriate manual for instructions on
adjusting the settings described below.
Kfactor
The Kfactor is a multiplier that is applied to the controller’s differential pressure reading. Its default value is dependent on the
valve size being used.
Increasing the Kfactor from its default value will increase the flow reading. Decreasing the Kfactor from its default value will
decrease the flow reading. To determine the Kfactor required, simply use the following formula.
 =′ 
 
Recommended Balancing Procedure
Below are the recommended steps to take when balancing VFX.
1. Depending on the balancer’s process (which varies based on local requirements, balancer’s test method, etc…), one of the
following will be required:
a. One airflow will be measured. Typically, the Max Scheduled airflow for the valve.
b. Two airflows will be measured. Typically, the Max Scheduled and Min Scheduled airflow for the valve.
2. Calculate a Kfactor adjustment for any readings taken.
3. If two airflows are measured and do not result in the same Kfactor adjustment, apply Kfactor that applies best to both
readings.