TABLE
OF CONTENTS
1. Scope
of Work .
2. Definitions
and Abbreviations
3. References
4. Responsibilities .
5.
Safety
6. Procedure
7. Procedure for Testing and Balancing
8. Equipment
9. Instruments & Calibration
for Testing
10 Attachments document's
details
* SATIP-K-001-12
* SAIC-K-4041
* SAIC-K-4042
* SAIC-K-4043
* SATR-K-4006
1. Scope
·
The scope of this document is to define the method to be
applied for testing, adjusting & balancing of HVAC Air systems, sub-systems,
related equipments and their allied components.
2. Definition & Abbreviations
2a. Definition
i.
Adjust: To regulate fluid flow rate and air
patterns at the terminal equipment, such as to reduce fan speed or adjust a
damper.
ii.
Balance: To proportion flows within the
distribution system, including sub mains, branches, and terminals, according to
indicated quantities.
iii.
Barrier or Boundary: Construction, either
vertical or horizontal, such as walls, floors, and ceilings that are designed
and constructed to restrict the movement of airflow, smoke, odors, and other
pollutants.
iv.
Draft: A current of air, when referring to
localized effects caused by one or more factors of high air velocity, low
ambient temperature, or direction of airflow, whereby more heat is withdrawn
from a person's skin than is normally dissipated.
v.
NC: Noise criteria.
vi.
Procedure: An approach to and execution of a
sequence of work operations to yield repeatable results.
vii.
RC: Room criteria.
viii.
Report Forms: Test data sheets for recording
test data in logical order.
ix.
Static Head: The pressure due to the weight
of the fluid above the point of measurement. In a closed system, static head is
equal on both sides of the pump.
x.
Suction Head: The height of fluid surface
above the centerline of the pump on the suction side.
xi.
System Effect: A phenomenon that can create
undesired or unpredicted conditions that cause reduced capacities in all or
parts of a system.
xii.
System Effect Factors: Allowances used to
calculate a reduction of the performance ratings of a fan when installed under
conditions different from those presented when the fan was performance tested.
xiii.
TAB: Testing, adjusting, and balancing.
xiv.
Terminal: A point where the controlled
medium, such as fluid or energy, enters or leaves the distribution system.
xv.
Test: A procedure to determine quantitative
performance of systems or equipment.
xvi.
Testing, Adjusting, and Balancing (TAB) Firm:
The entity responsible for performing and reporting TAB procedures.
2b. Abbreviations
1.
Clients
: Saudi Aramco / Samsung Saudi Arabia
2.
Sub
Contractor : Construction and Installation Contractor
3.
TAB
Contractor : Commissioning Contractor; 3rd Party of Testing,
Adjusting and Balancing (TAB Contractor).
4.
Vendor :
HVAC Equipments Manufacturer
5.
CA : Commissioning
Authority
6.
CX : Commissioning
7.
MC : Mechanical
Contractor
8.
EC : Mechanical Conctractor
9.
CC : Controls Contractor
10.
GC : General Contractor
11.
CPI :
Commissioning,Pre-Inspection Checklist
12.
RFA :
Request for Assessment
13.
OMS : Operations
& Maintenance Staff
14.
NEBB : National
Environmental Balancing Bureau
15.
TQ :
Technical Queries
3. References
·
ASHRAE
Commissioning Guidelines
·
ASHRAE
Standards
·
National
Environmental Balancing Bureau Procedural Standards (NEBB)
4. Responsibilities
·
Installation
contractor to confirm the complete operational readiness of the HVAC system to
allow the pre-commissioning task and checklist to be performed.
·
Installation
contractor shall verify the installation conformity to the design drawings in accordance with the
specifications and approved Technical Query.
·
Installation
contractor to provide operation and maintenance manuals. Manual contents are
defined as the manufacturer’s data
on the HVAC equipment installed and must
include the following:
1)
The manufacturer’s method for Pre-Commissioning,
TAB and performance Testing of the HVAC equipment, systems, subsystems and its
components for correct operation under
actual load conditions.
2)
The
manufacturer’s recommended tolerance for
maximum and minimum operating conditions; Flow, RPM, etc.; proper
locations; and unit at design flow rate.
3)
The recommended correction to allow adjustment of
air terminals.
4)
A list
of spare parts, identification numbers and diagrams of their pressure drops for
air systems.
·
Commissioning
contractor to inspect the system after site readiness notification to determine
that the system is actually complete and
ready to be started for TAB activities.
·
TAB
contractor to field verify A & K factors for applicable air terminals, if
required.
·
TAB
contractor to test & adjust the minimum and maximum air flows as required
for the project.
·
TAB
contractor ensures all devices must be calibrated and provided with test certificate
reports which shall be submitted to QC prior to start the TAB activities.
·
TAB
Contractor ensures that all equipments shall be delivered as per Design & Specification.
·
TAB
contractor to make all field adjustments required for balancing and prepares certified report.
·
TAB
contractor to prepare a final TAB report and documentation of final system
& component balance conditions.
·
Commissioning
contractor to document any deficiencies prior to performance testing, which prevent the system from being properly verified and any
conditions caused by a deficiency and give them the responsible representative
for correction.
5. Safety
·
Every
TAB team member has a responsibility to work in a safe manner, not to interfere
with anything provided for their safety and to report any hazardous situation
without delay to their immediate supervisor on the project site.
·
Safety
is everybody’s responsibility. Each has a duty to the other to maintain a working
environment that is, so far as is practicable, free from hazards and risk of
injury to personnel. The elimination of
injury to employees and a reduction in
the amount of damage or loss of
the equipment or materials must be of utmost concern to all agencies involves
in the TAB process for HVAC system.
·
Where
it is impossible to provide a hazard-free environment, TAB contractor accepts
the responsibility to provide protection, advice and information that will help combat
particular hazards.
6. Procedures
6.1 Equipment Start Up
·
After
pre-inspection is complete, equipment shall be systematically started up
according to the approved start up forms procedures by Luberef.
·
Representatives
of equipment vendors shall be present to
observe and to assist in the start up
process.
·
Start
up of all HVAC air side equipment and systems shall be done as per
manufacturer’s recommendations.
6.2 Preparation
A. Prepare a TAB plan that includes strategies
and step-by-step procedures.
B. Complete system readiness checklists
and prepare system readiness reports. Verify the following:
I. Permanent
electrical power wiring is complete.
II. Automatic
temperature-control systems are operational.
III. Equipment
and duct access doors are securely closed.
IV. Balance Damper, Fire Damper,
Combination smoke fire dampers are opened.
V. Isolating
and balancing valves are open and control valves are operational.
VI. Ceilings
are installed in critical areas where air-pattern adjustments are required and
access to balancing devices is provided.
VII. Windows
and doors should be closed so indicated conditions for system operations can be
met.
6.3 Testing & Balancing
Testing
and Balancing shall be conducted after
start up check by TAB agency/contractor and shall be conducted as per the
following:
·
Latest
version of NEBB procedural standards and the project specification with
approved TQs if applicable.
·
Instruments
used by the TAB for taking measurements shall comply with the specifications listed in table enclosed with this document.
7. Procedure of Testing, Adjusting and Balancing
TAB shall be done as per latest NEBB procedural
standards:
·
In order to achieve the purpose of Testing,
Adjusting and Balancing of HVAC system the above referred method shall be
applied.
·
To
ensure that the basic procedures are followed in TAB processes, the
following general procedures are described.
7.1. General Testing
Procedures for Air Systems
These
procedures shall be applied to all measurements encompassed in TAB to complete
the report forms applicable as per the attachments.
1.
Perform testing, Adjusting and balancing
procedures for each system according to the procedures contained in Air
Conditioning Systems "NEBB's Procedural Standards for Testing, Adjusting
and Balancing of Environmental Systems".
2.
Cut insulation, ducts, pipes, and equipment
cabinets for installation of the test probes to the minimum extent necessary to
allow adequate performance of procedures. After Testing, Adjusting and Balancing,
close probe holes and patch insulation with new materials identical to those
removed. Restore vapor barrier and finish according to insulation
Specifications for this Project.
3.
Prepare
test reports for both fans and air outlets. Obtain manufacturer’s outlet factors and recommended testing procedures.
Cross check the summation of required outlet
volumes with required fan
volumes.
4.
Determine
the best locations in main and branch ducts for accurate duct-air flow measurements.
5.
Check
air flow patterns from the outdoor-air louvers and dampers and the return and
exhaust air dampers through the supply-fan discharge and mixing dampers.
6.
Locate
start–stop and disconnect switches, electrical interlocks, and motor starters.
7.
Verify
that motor starters are equipped with
properly sized thermal protection.
8.
Check
dampers for proper position to achieve desired airflow path working condition
(open and close).
9.
Check
for airflow blockages (Filters).
10. Check condensate drains for proper connections and
functioning.
11. Check for proper sealing of air-handling-unit components.
12. Mark
equipment and balancing device settings with paint or other suitable, permanent identification material, including
damper-control positions, valve position indicators, fan-speed-control levers,
and similar controls and devices, to show final settings.
13. Report
deficiencies discovered before and during performance of TAB procedures. Observe and record system
reactions to changes in conditions. Record default set points if different from
the indicated values.
7.2. Procedures for
Constant-Volume Air System
1. Adjust fans to deliver total indicated airflows within
the maximum allowable fan speed listed
by fan manufacturer.
2. Where sufficient space in ducts is unavailable for
Pitot-tube traverse measurements, measure airflow at terminal outlets and
inlets and calculate the total airflow.
3. Measure outlet static pressure as far downstream from the
fan as practical and upstream from restrictions in ducts such as elbows and
transitions.
4. Measure static pressure directly at the fan outlet or
through the flexible connection.
5. Measure inlet static pressure of single-inlet fans in the
inlet duct as near the fan as possible, upstream from the flexible connection
and downstream from duct restrictions.
6. Measure inlet static pressure of a double-inlet fans
through the wall of the plenum that houses the fan.
7. Measure static pressure across each component that makes
up an air handling unit, rooftop unit and other air handling and treating equipment.
8. Report the cleanliness status of filters and the time
static pressures are measured.
9. Measure static pressures entering and leaving other
devices, such as sound traps, heat-recovery equipment and air washers under
final balanced conditions.
10. Do not make fan-speed adjustments that result in motor
overload. Consult equipment manufacturer’s about fan speed, safety factors.
Modulate dampers and measure fan motor amperage to ensure that no overload will
occur. Measured amperage in full cooling, full heating, economizer and any
other operating mode to determine the maximum required brake horsepower.
11. Adjust volume dampers for main duct, sub main ducts and major
branch ducts to indicate airflows within
specified tolerances.
12. Where sufficient space in sub main and branch ducts is
unavailable for Pitot-tube traverse
measurements, measure airflow at terminal outlets/ inlets and calculate
the total airflow for that zone.
13. Measure static
pressure at a point downstream from the balancing damper and adjust volume
dampers until proper static pressure is achieved.
14. Remeasure each sub-main and branch duct after all have been
adjusted. Continue to adjust sub-main and main branch ducts to indicate airflows within specified tolerances.
15. Measure terminal outlets using direct-reading hood or
outlet manufacturer’s written instructions and calculating factors.
16. Adjust air outlets and inlets for each space to indicate airflows within specified tolerances of the indicated values.
Make adjustments using branch volume dampers rather than collar dampers.
17. Adjust each outlet in the same room or space to within
specified tolerances of indicated quantities without generating noise levels
above the limitations prescribed by the Contract Documents.
7.3. Flow Measurements
Procedure
7.3a Procedure for Pitot
Tube Traverse and Air Flow Hood
To accomplish
repeatable traverse measurements, take the measurements in a specific measured
pattern. There are two acceptable methods.
i. The equal area method.
ii. The log/Tehebycheff method.
iii. Locate a traverse position in a straight section of duct.
iv. Duct size must not change in a traversed section.
v. Face the Pitot tube into the air stream and parallel to
the air stream before taking measurements. Convert velocity pressure to FPM velocity
before averaging. Take traverse measurements in actual conditions and actual
cubic feet per minute (ACFM). Correct ACFM to standard CFM (SCFM) when
specified. Verify that the velocity measurements are acceptable. AMCA
Publication 203-N 90 states that a
traverse plane is suitable for flow measurements if more than 75% of the velocity pressure
readings are greater than 1/10 of the maximum velocity measurements.
vi. Airflow Hood is a multipurpose electronic air balancing instrument
primarily used for efficiently taking direct air volume readings at diffusers
and grilles. Designed to fit
over standard sized grilles and diffusers, this digital Balometer feature is a
24” x 24” hood opening. The hood channels air flow through the base to directly
measure air volume in cubic feet per minute. Weighing less than eight pounds,
the Balometer allows single operator use and reduces user fatigue. It features a detachable micro manometer for increased
flexibility in multiple measurement applications. Offering durable operation,
this lightweight, ergonomically designed Airflow capture hood kit saves time
and money by combining multiple measurement tools into one package. A
professional tool for airflow commissioning and balancing with quick and simple
hood changes. Measuring range from 50 to 3500 m3/h / -2500 Pa to 2500 Pa,
handles integrated in the measuring unit. Calculation of average airflow with
easy-access button, display of data sets, recording and downloading of datasets
on PC, via LPCF / DATALOGGER software.
7.3b. Procedure for
Electric Power Measurenent
Electrical data measurements include
the following:
i. Amperage readings on each phase.
ii. Voltage readings on each phase.
iii. Balanced and unbalanced KW readings, when applicable
iv. Power factor, when applicable.
v. As additional data as required to verify performance.
vi. Take motor KW measurements to verify horsepower before
recommending the changing of motors.
vii. Comply with proper safety procedures, including the use
of electrical gloves when taking power readings on approved forms that
correspond to the equipment being tested.
7.3c. Procedure for
Rotational Speed Measurements
i. Verify that the vibration Isolators are properly
installed.
ii. Select the type of appropriate instrument required for
the test.
iii. Remove the belt
guards on each unit with the unit off.
iv. Verify that the drive alignment is correct.
v. Verify that belt tension is correct.
vi. Turn the unit on
and with adequate clearance, measure RPM
vii. Take final RPM measurements with the unit at balanced
conditions.
viii. Measure RPM at each speed mode operation.
ix. Take motor RPM measurements to verify the motor load. RPM
changes with load on the motor, which affects the fan RPM.
x. Reinstall the belt guard with the unit off.
xi. Comply with proper safety procedures, including
preventing the loose clothing or hair from being caught in the rotating
components.
xii. Record all rotational test measurements on approved forms
that correspond with the equipment tested.
xiii. Use a photo tachometer or strobe when access will not
allow a direct reading tachometer to be used.
7.3d. Procedure for
Static Pressure Measurements
i.
Take
the fan suction pressure in the eye of the fan wheel inlet or fan inlet plenum.
Do not include inlet vanes.
ii.
Take
the fan discharge pressure at the discharge of the fan outlet. If the fan has
an outlet damper as part of the fan, do
not include the damper. Fan pressure data, along with the fan RPM, motor brake
horsepower, and fan curve can be used to determine the fan performance and
system effect.
iii. Measure the external static pressure in the unit supply
outlet duct and unit return air inlet duct. The
external unit pressure equals the supply outlet duct pressure minus the
return inlet duct pressure.
iv. Measure the pressure losses across each related device in
the unit, i.e., filters, heating coils, cooling coils, damper section, etc.
v. For static controlled systems, measure and record the
static pressure at the control static pressure sensor location.
vi. Compare and review static pressure measurements against
the manufacturer’s submittal data for differences that could affect the system
performance.
7.3e. Procedure for
Basic Temperature Measurements
i. Use thermometers with
current calibration records and compare them to each other for a matched
set at the time of the test.
ii. Psychrometer/Digital Thermometer to the point required
for accurate measurements according to the manufacturer’s directions.
iii. The test location for a single point measurement should
be at the average fluid temperature (air or water). If the average temperature cannot taken at one
location, then take multiple points in a traverse fashion and record the
average. Test wells in pipes, must
protrude into the pipe to allow for accurate measurement (approximately 50% of
the pipe diameter). Add heat transfer
fluid to wells for accurate temperature measurements.
iv. Avoid effects of radiation, i.e., avoid measuring next to an electric heating coil element.
v. Allow time for the thermometer to reach equilibrium with
the fluid (air or water) being measured.
Take periodic readings without removing the thermometer from the fluid
until the temperature remains
essentially constant more than a 30 second time period. When using a 0.1” F
thermometer and conducting a field performance or witness test, once the
thermometer has reached equilibrium, record three readings at five second
intervals and use the average as the station reading.
vi. In HVAC applications, avoid surface temperature
measurements unless no other method is available. The surface temperature will
not be the true fluid temperature, and this
method has a great deal of error. If a surface temperature is used, give
great care to cleaning the pipe so there is good contact with the thermometer
and the pipe. Insulate over the thermometer and pipe to reduce the ambient air
effect on the temperature readings. This method is best suited to determine the
temperature drop between a supply pipe and a return pipe on coils or fin tube radiation.
vii. Take the wet bulb temperatures in airstreams and in
ambient air using an appropriate thermometer with a cotton wick installed over
the sensing portion of the thermometer. The wick should have extra length to
help retain moisture during the measurement period, and may be extended to a water reservoir for a
prolonged measurement. The wick should be wetted with distilled water for
performance or witness testing. Clean, fresh water is adequate for more field
testing as the error, if any, is
not significant. The airflow over
the wick shall be approximately 1,000fpm for wet bulb testing.
7.3f Procedure for Vibration Measure Measurements.
i.
Perform
vibration measurements when other building and outdoor vibration sources are at
a minimum level and will not influence the Measurements of equipment being
tested.
ii.
Turn
off equipment in the building that might interfere with testing.
iii.
To
Restrict people from occupying areas where human activity may affect accuracy
of measurements.
iv.
Exterior
vibration sources; i.e. trains, roadway traffic, adjacent construction
activities, etc.
v.
Attach
and secure the vibration transducer in accordance with the latest edition of
the NEBB Procedural Standards for Measurement of Sound and Vibration.
vi.
Measure
and record, on all pumps and fans over 3 HP, and all chillers and compressors
over 5 HP, at discrete frequencies or in 1/3 octave bands as follows:
a. Discrete vibration levels from 1 to 200 Hz in 1 Hz
increments, or
b. In each 1/3 octave band from 12.5 Hz to 200 Hz.
vii.
Measure
and record equipment vibration, bearing vibration, equipment base vibration,
and on building structure adjacent to equipment. Record velocity and
displacement readings in the radial vertical, radial horizontal and axial
planes, where measurements can be performed safely.
7.3g Procedure for Sound Level Measurements.
i.
Close windows and doors to the space.
ii. Perform measurements when the space is not
occupied, or when the occupant noise levels from other spaces in the building
and outside are at a minimum, or do not affect Sound readings.
iii.
Clear the space of temporary sound sources so
unrelated disturbances will not be
Measured. Turn off all sound sources
(personal computers, printers, fax machines, etc.) in the space that may affect
sound readings.
iv.
Positional
sound level instrument during measurements to achieve a direct line-of-sight
between the sound source and the sound-level meter.
v. Take
sound measurements at a height approximately 48 inches above the floor and at
least 36 inches from a wall, column, or any other large surface capable of
altering the measurements.
vi. Take
sound measurements in dB (linear or flat), with the slow time constant, in the
octave bands from 31.5 to 8000 Hz.
vii. Take sound measurements with the HVAC systems
off to establish the background levels
and take sound measurements with the HVAC systems operating. Calculate the
difference between measurements. Apply a correction factor depending on the
difference and adjust the measurements.
viii. Sound
testing in all occupied space horizontally and vertically adjacent to all.
ix. Perform sound testing at 10% of locations on
the project for each type of the following spaces. For each space type tested,
select a measurement location that has the greatest anticipated sound level. If
testing multiple locations for each space type, select at least one location
that is near and at least one location that is remote from the predominant
sound source.
1. Private
office.
2. Open
office area.
3. Conference
room.
4. Auditorium/large
meeting room/lecture hall.
5. Classroom/training
room.
6. Patient
room/exam room.
7. Sound
or vibration sensitive laboratory.
8. Hotel
room/apartment.
9. Library
open space.
10. Public
areas (such as lobbies, hallways, break rooms).
x.
Perform sound testing in all spaces with a
design criterion of NC or RC 25 or as
per Client Specification.
8. Equipment Testing
8.1. Air conditioning units {Air Cooled Condensing Unit
(ACCU), Air Handling Unit(AHU), Package Unit(PU), Split Unit(SU), Fan Coil Unit(FCU),
Chemical Filtration Unit(CFU) and Exhaust Fan (EF) } : As per the application
forms in latest NEBB Procedural standard.
8.2 Air Outlet: As per the applicable forms in latest NEBB Procedural standard.
9. Instruments & Calibration for Testing
·
TAB
instrumentation shall comply with the specification of Table-4 Section 4 of
NEBB Procedural Standards, Seventh Edition and Quantity, Accuracy, and
Calibration.
·
In case
of any conflict between the above measurements and NEBB standards, precedence
shall be given to the NEBB Procedural Standards.
10. Attach following documents
·
SATIP-K-001-12
(Testing, Adjusting and Balancing (TAB)
of HVAC System)
·
SAIC-K-4041 (Review
of HVAC System Testing Organization Qualifications Including TAB Personel/Technician)
·
SAIC-K-4042 (Review
of HVAC System Testing, Adjusting and Balancing Procedures including Test Equipment and
Certificates)
·
SAIC-K-4043 (Final
Inspection of HVAC System)
·
SATR-K-4005 (Laboratory Hood Test)
·
SATR-K-4006 (Conduct HVAC System Testing, Adjusting and Balancing)
(HVAC System Testing, Adjusting and Balancing Report)
·
Job Safety
Analysis (JSA) Or Job Hazard Analysis (JHA).
Prepared by M.Ajmal Khan.
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