METHOD STATEMENT FOR HVAC CONTROL WORKS

METHOD STATEMENT FOR HVAC CONTROL WORKS

CONTENTS

  1. INTRODUCTION
  • PURPOSE
  • SCOPE
  • REFERENCES
  • DEFINITIONS
  • ORGANIZATION CHART
  • DUTIES AND RESPONSIBILITIES
  • METHOD STATEMENT FOR HVAC CONTROL PANEL AND DEVICES INSTALLATION
  • METHOD STATEMENT FOR CABLE TRAY, CONDUIT PIPE AND CABLING/WIRING INSTALLATION
  1. METHOD STATEMENT FOR HVAC CONTROL SYSTEM TEST
  1. QUALITY CONTROL
  1. SAFETY PLAN
  1. INTRODUCTION

This method statement details the method of performing the various activities involved in the course of works for field installation works of HVAC Control system for ERC REFINERY PROJECT. These method statements are applicable only for the HVAC Control system Installation of various building in this project.

  • PURPOSE

This method statement gives guidelines contained herein so as to ensure that the job execution complies with the requirement of the specification and the authorities concerned and serves the intended purpose to satisfactory level.

  • SCOPE

This method statement covers the nature and type of work for the installation of HVAC Control Panel, Cable, Cable Tray and Conduit works in the building and frequency at which inspections are to be carried out.

  • ARI  : Air–Conditioning and Refrigeration Institute
    • ASHRAE:American Society of Heating Refrigerating and Air Conditioning Engineers Inc.
    • NEBB : National Environmental Balancing Bureau
    • NFPA : National Fire Protection Association
    • UL: Underwriters Laboratories, Inc.
    • IEC : International Electro technicalCommission
    • ISA : Instrument System and Automation Society
    • ISO : International Organization for Standardization
    • Project Specifications
    • Project IFC Drawings
    • Inspection and Test Plan for HVAC System
  • DEFINITIONS
  • DUTIES AND RESPONSIBILITIES

All workers who are involved in HVAC Control work shall be oriented to the nature of work, to ensure that the procedure is followed accordingly and to assure that the safety requirements is strictly adhered.

The contractor shall check all documents to ensure that the work is being carried out following the latest revision of issued IFC drawing.

Staff and foreman involved in the Works, whether he is working with GS E&C or Subcontractor, shalltake the responsibilities according to his entitled positions and the Works.

  • SITE MANAGER

The Site Manager shall be responsible for the over-all direction, coordination and control of all site activities and all construction works including HSE and quality control, etc.

  • CONSTRUCTION MANAGER

The Construction Manager shall report to and receive technical direction from the Site Manager and developing and arranging the site construction team to the site necessary to manage and supervise theconstruction works including HSE and quality control, etc. The Construction Manager shall be responsible for the overall implementation and monitoring of all the activities for the successful completion of construction works.

  • QUALITY CONTROL INSPECTOR

The QC Inspectorshall be responsible for performing the inspection and test in accordance with Inspection and Test Plan as approved by Company. And also QC Inspectorshall prepare hold point inspections and the corresponding work releases by reviewing records and test results as proof that work inspected conforms to specification.

  • SAFETY SUPERVISOR

The Safety Supervisor shall be responsible for the organization of Health Safety and Environment (HSE) activities on site. To ensure that all safety plans, safety rules and regulations are being implemented accordingly. And also Safety Supervisor shall prepare prior to the start of the work a safety plan that must be implemented and observed during the HVACEquipments, Ducts and Refrigerant piping works and safety awareness of workers during the activity

  • HVAC CONTROL SITE SUPERVISOR

The HVACCONTROL Supervisor shall be report to and receive project direction from the construction manager.The HVACCONTROL Supervisorshall be directly involved in the planning and execution of the activities in the HVAC Control Panel, Cable, Cable Tray and Conduit works. And also HVAC CONTROL Supervisor shall prepare prior to the start of work, a safety action, controlling of construction schedule, including submittal and inspection of materials that must be implemented and observed during the HVACCONTROL work.

  • ELECTRICAL(Cable, Cable Tray & Conduit) FORMAN

The Forman shall be responsible for the direct execution of works involve in the HVAC Control work according to the plan and shall directly control and give instruction to the working personnel. The Forman shall also ensure that works are done with utmost regard to safety and quality.

  • METHOD STATEMENT FOR HVAC CONTROL PANEL AND DEVICES INSTALLATION

All Panels and Devices shall be inspected by contractor and company prior to start work and after inspecting the Panels and Devices, protect them properly in storage until their actual installation at site. The Contractor shall be installed HVAC Control Panels and Devices as per approved layout.

  • HVAC Control Panel(HCP) Installation
    • HVAC Control Panels shall be positioned on the foundation so that whendoors are fully opened, covers removed, controls and connections shall be easilyaccessible.
    • The orientation shall be checked to ensure the subject area is not obscured by pipes orstructures and the accessibility for maintenance is maintained.
    • Prior to installing the support, the fixing points and bases shallbe checked to ensure their alignment and level is correct.
    • Fabricate/assemble HVAC control panel frame/support as per standardinstallation drawing and suitable to the requirement of site.
    • Install these frames/supports at site in accordance with the elevation shown on thelatest IFC drawing.
    • Check the horizontal and vertical alignment by using a Sprit Level.
    • Fixing Bolts shall be fully tightened to the base frame after verifying the alignment.
    • Supports/frames installation on steel structures/concrete shell be done by using nutsand bolts or by welding as indicated in the standard installation detail. Follow projecttechnical specification of welding.
    • All material used for brackets give adequate coating of Galvanized primer.Brackets and Supports shall be adequately protected against corrosion by theapplication of touch up paint to any areas of damage. Follow project technicalspecification of painting.
    • Ensure installation of correct tagged HVAC control panel as per the respectivedrawing.
    • Make sure Earthing of the supports/frame, HVAC control panels are connectedas per the Earthing layout.
    • After completion of installation protect the HVAC control panels with aplastic cover of the packing cover to prevent any scratches , mechanical damages orpainting spots, which are likely to occur during any other construction activities.
    • If punch and comments are issued during inspection, all punch and comments shouldbe rectified until all inspection test report are signed off.
  • HVAC Control Devices Installation
    • Temperature Sensor
  • Installall sensor and instrumentation according to engineering design standard.
  • Smoke detector shall be placed in return duct. Temperature sensor locations shall be readily accessible, permitting quick replacement and servicing without special tools. Thermostat shall be near in return duct.
  • Use of sensors shall be limited to its duty, e. g., duct sensor shall not be used in lieu of room sensor.
  • Mount sensors rigidly and adequately for the environment within which the sensor operates
  • Permanently mark terminal blocks for identification. Protect all circuits to avoid interruption of service due to short-circuiting or other condition.
    • Pressure Sensor
  • Installpressure sensor according to engineering design standard.
  • Install duct static pressure sensor tips downstream of airflow.
    • Actuators
  • Mount damper actuator according to manufacturer’s written instructions.
  • Must provide integral spring return to ensures level of return torque.
  • Two hours fire rated and less than 10 second time to open/close the damper.
  • Check operation of damper/actuator combination to confirm that actuators modulates damper smoothly throughout stroke to both open and closed position.
    • Flow Switch
  • Installflow switch according to manufacturer’s written instruction.
  • Assure correct flow direction and alignment.
  • METHOD STATEMENT FOR CABLE TRAY, CONDUIT PIPE AND CABLING/WIRING INSTALLATION

Cable tray, conduit pipes, supports and fittings shall be check in accordance with the Project specification, code and standard.Cable sizes, type, and color code, number of wiresshall be check in accordance with the design specification, codes and standard.All the control materials will be fabricated by approved manufacturer or Subcontractorand will be delivered to site (by GS).

  • Installation of Cable Tray
    • Allcable trays must be erected and constructed as perdesign specificationrequirementsand standard and drawings issued for construction.
    • All cable tray’s route, elevation, dimension shall be check and verified prior toinstallation.
    • Install strong anchor to the upper slab or on where cable trays are tend to install.
    • Cut required length of threaded hanger rod depending on the bottom elevation of cable tray.
    • Hang cable tray by hanger rail and threaded hanger rod.
    • The standard length of cable tray must be followed during the construction as per project specification.Properly tighten all bolts / nuts that fastened joint plates, cable trays and supports. Beforetightening the bolts / nuts, make sure that the correct elevations, dimensions are properly.
    • Checked and verified as perlatest issued for construction HVAC control layout plan drawings.
    • All cable trays interconnection must be bonded with jumper, and the end side of the cable tray must be connected and properly earthed.
    • After installing all cable trays, visual checking should be done if there are any misalignments, loose fastener, support or any damage that may cause corrosion or rust, if any, these shall be retouch by approved coating.
    • All cables on cable tray must be covered with cable tray cover when specified on drawings after the inspection is conducted.
  • Installation of Conduit Pipe
    • All conduits shall be rigid metal conduits, unless otherwise shown or specified.
    • Conduits carrying instrumentation wiring and conduits carrying low voltage power and control wiring may be run in the same trench if all conduits are rigid metal or intermediate metal. Damaged, dented, flattened, or kinked conduit pipe shall not be used.
    • Accurately measured the length of each pipe segment.
    • Cut the pipe to the measured length, care must be taken to ensure the pipe is not deformed while being cut.
    • The cut must be square to the run of the pipe so the pipe will set properly the treading machine.
    • Ream all cut pipe ends to the full inside diameter of the pipe to remove the sharp edge created by the cutting operation.
    • Carefully bend conduit pipe with approved pipe bender when required for bending.
    • Use strong anchor, U–channel, hanger rod, and pipe clamp in installing conduit pipes to the upper slab and or wall.
  • Cabling and Wiring
    • Make sure that all entire cable routes are completed and free from obstruction, debris, sharp materials etc…
    • Check the cable size, number of cable, conduit size which is appropriate for the control component to be used in accordance with the HVAC control cable list and HVAC control wiring plan.
    • Measure appropriate length of cable or wire to be used.Used correct tools in cutting stripping and splicing the wire or cable.
    • No joints or splices to all cables/wires inside conduit pipes and cable trays.
    • Cables/wires shall be arranged and tied properly inside the cable tray. Cables to be installed in conduit pipes, cables shall be pulled using steel guy wire with care to avoid straining, twisting or entangling of cables.
    • To verifywiring is accordance with Control vender standard regulation.  Inspection will include, color codes, wiring layout, cable duct loading, fusing/power distribution and verification of all I/O’s wired to termination’s.
  • Termination
    • All wires and cables shall be terminated to proper terminals or location in accordance with HVAC control cable list and HVAC control wiring diagram.
    • Conductors shall be connected to equipment,controls and instrument by using terminal lugs. Terminal lugs must coincide to the size of the conductor to be used.
    • Appropriate crimping tool, cable stripper and wire stripper must be used.
    • Marking for cable/wire identification shall be provided at each termination point.
    • Termination from field instrument, switches and sensor to the HVAC control panel shall be properly check for proper connection and tag.
    • Cable glands or sealing fittings when required shall install at the entries to equipment and instruments in accordance with design & specification.
    • Cover shall be replace after the inspection and testing, all junction boxes, instruments and control panels.
    • Field inspection shall be performed in accordance with inspection and test plan for HVAC Control system.
  • METHOD STATEMENT FOR HVAC CONTROL SYSTEM TEST

Testing shall be carried out under the supervision of Contractor & Company with allcalibrated tools and equipment’s.Prior to the system being released from manufacturing, a route traveler will be placed in a plastic holder with a control vendor route card.Upon completion of each test, test personnel will sign and date a control vendor route card.

Field test / Inspection report format will be used for this purpose.

  1. Continuity and Megger Test
    1. Before commencing the termination on all field instruments, junction boxes, control panels etc., continuity and megger test must be done
    1. .Multi- tester and Meggertest shall be used in checking the insulation and continuity of the conductors.
    1. Multi- tester/buzzer shall be connected to both conductors on one side while the other end of the conductors shall be shorted/open. Therefore the continuity of the conductorshall be confirmed.
    1. Megger tester shall be connected to both conductors on one side while on the other end of the conductors shall be open; therefore the insulation test shall be confirmed.
    1. If conductors failed continuity or megger test conductors shall be replace.
  1. Site Acceptance Test

The SAT(Site Acceptance Test Procedure) provides a structured method for the post manufacturing test of allHVACcontrol system forERC Refining Project-Building Package01.

When all the tests in this document have been completed, signed, dated and stamped, the system will be ready for loop checking & commissioning.

  1. Hardware Check

A mechanical inspection will be performed to verify that the system has been constructed in accordance with the system design and that proper workmanship has been executed in the assembly and wiring of the system.

  1. Mechanical Construction

Compare the arrangement of the system with the HCP Panel Layout Drawings from to ensure that it has been manufactured and assembled correctly. Any features, configurations or options called for on the drawings will also be verified.

  • Wiring

To verify wiring is in accordance withCompany. Inspection will include, color codes, wiring layout, cable duct loading, fusing/power distribution and verification of all I/O’s wired to termination’s.

  • Paint Finish

Verify that the paint work is free of defects such as variations of shades, uneven or crazed finish or scratches.

  • Assembly Items

All items shown in the bill of materials on the HCP PanelLayout.

  1. Electrical Test
  2. Earth Bonding

Secure the Panel Ground Bus-bar to the local factory earth point before applying power to the system. Check the earth bonding between the Panel Ground Bus-bar and all exposed metal surfaces.

  • Instrument Ground Continuity

Where multiple busbars are connected together, verify that the wiring does not create earth loops.

  1. Power up Check
  2. The purpose of this test is to verify that the power distribution systems function as designed and as detailed in the approved documents.
  3. Check that no fused breakers and fuses of the proper amperage are installed in all locations. Trip all circuit breakers and open all fuses. Apply power to incoming power terminals. Referring to the approved documents, use a multi-meter to check power points throughout the system.
  4. In sequence, check each NFB breaker or fuse for zero volts on the destination side then close the NFB breaker or fuse and verify that the appropriate voltage appears on the switched side.
  5. As each NFB breaker is tested, leave the breaker in the ON position so that any connection between different power circuits can be detected.
  6. De-energize and reinstate each NFB breaker or fuse in turn and verify that the correct subsections (circuits) are isolated and restored as appropriate. At the same time verify correct operation of any power indicators supplied with the system.
    1. Control Logix PLC System Testing
  7. Module Installation

Install all electronic modules and ensure they are properly clamped and seated, with retaining screws tightened and/or ejector clamps latched closed.

  • Power On Verification
  • The Processor transmits status information as it powers up, monitor this information to ensure the module powers up correctly.
  • Apply power to the system and monitor the status information as describedabove.The PLC system will take a few minutes to power up. Linesoftext should appear on the terminal reporting the activity of the PLC system as it powers up. The last line of text should be “RUN”, this indicates that the PLC system has successfully powered up.
  • Upon successful power up of the PLC system, verify the module status is as indicated below
  • Loading the Application Software

Using the Loader, open the [AB Logix5000] program. From the list of projects, open the project specific application. Refer to the [AB Logix5000] User’s Guide for further details, or request engineering assistance to perform this task.

  1. Relay Sequence Testing[Input /Output (I/O) Test]

Install all electronic devices and ensure they are properly clamped and seated, with retaining screwstightened and/or ejector clamps latched closed.

  1. Analog Inputs
  2. This test will be performed on each channel of each module. Operate the potentiometer and monitor its input variable on the Loader running [AB Logix5000]PLC program.
  3. Verify that with the potentiometer 4mA, the input variable indicates 0% of scale range on Loader and Touch Screen on panel front door.
  4. Verify that with the potentiometer 12mA, the input variable indicates 50% of scale range on Loader and Touch Screen on panel front door.
  5. Verify that with the potentiometer 20mA, the input variable indicates 100% of scale range on Loader and Touch Screen on panel front door.
  6. When input variable of scale range is more/less than the alarm set value, verify that monitoring switch variable turn ON/OFF on Touch Screen.
  7. Analog Outputs
  8. This test will be performed on each channel of each module. Force to entry output variables value on the Loader and measure the current at terminal block related to analogue output.
  9. Verify that with the forced output value 0% on loader, the output current on Multi-tester indicates 4mA.
  10. Verify that with the forced output value 50% on loader, the output current on Multi-tester indicates 12mA.
  11. Verify that with the forced output value 100% on loader, the output current on Multi-tester indicates 20mA.
  12. Digital Inputs
  13. This test will be performed on each channel of each module. Operate therelated field instruments and monitor its input variable on/off the Loaderrunning [AB Logix5000]PLC program.
  14. Short/Open the correct terminal in the Marshalling cabinet as mentioned in the Terminationdiagram.
  15. Verify that with the switch “CLOSED”, the module front panel channel status LED and input variable turn “ON” on the Loader and Touch Panel.
  16. The other way, verify that with the switch OPEN, the module front panel channel status LED and input variable turn OFF on the Loader and Touch Panel.
  17. DigitalOutputs
  18. These tests will be performed on each channel of each module. Lock output variables ON and OFF on the Loader and monitor their Test Trolley lamps or LED status of module.
  19. Check for Circuit Close / Open using the multi meter connected to the terminals in theMarshalling cabinet as mentioned in the Termination diagram
  20. Verify that with the output variable forced ON, the module front panel channel status LED and safety relay or general relay lamps turn ON.
  21. The other way, verify that with the output variable forced OFF, the module front panel channel status LED and safety relay or general relay lamps turn OFF
    1. Fault Tolerant Tests
  22. Redundant Power SupplyUnitTest
  23. Verify that the system is operating correctly and that no system faults are present.  Monitor the application logicandfield I/O and verify that no spurious trips occur during these tests.
  24. Trip each redundant Power Supply Unitfeed one at a time and verify that the other Power Supply Unit feed(s) are still healthy. Verify that the system is operating correctly and that the only faults present are those associated with the tripped power feed. Repeat the procedure for all redundant power feeds.
  25. Redundant CPUModule Test
  26. Verify that the system is operating correctly and that no system faults are present.  Monitor the application logic and field I/O and verify that no spurious trips occur during these tests.
  27. Turn off no fused breaker for 1st CPU rack installed LOGIXprimary CPU module and primary CPU module is tripped at a time.
  28. Verify that the other secondary CPU module is still running and network between Touch Screen must be connected. Verify that the system is operating correctly and that the only faults present are those associated with the failedCPU module.  Repeat the procedure for all redundant CPU modules.
  29. QUALITY CONTROL
  1. Quality Control Plan
    1. Aquality assurance system shall be established to ensure conformance to related standards, codes, specification and procedures.
    1. Site Management, Supervisors and Safety Officer will closely supervise and monitor all phase of works to ensure full compliance with the procedures of Safety and work methodology.
    1. Significant stages of work shall be ensured by Site Supervisor /Quality Control Inspector to be conforming to the drawings and specification including:
  2. Use of approved materials.
  3. Set out of work before commencing installation.
  4. Check installed materials.
    1. Inspection TestRequest (ITR) shall be submitted 24 hours before the date and time of inspection for each stage of work as per approved inspection and Test Plan.
  1. Inspection and Test Plan
    1. All inspections and tests as identified in the Inspection and Test Plan.
    1. Inspection and Test Plan shall be completed by the SUB COTRACTOR and will be reviewed and approved by the CONTRACTOR.
  1. SAFETY PLAN

The responsible supervisor will periodically check the condition of the barriers, and where necessary refurbishment will be conducted.

  1. Safety Role and PTW
    1. Appropriate PTW is introduced and applied for approval from the central Safety Management.
    1. Training programs and competence standards are established and maintained.
    1. Monitoring/auditing/reviewing of PTW system is established and maintained.
    1. PTW is processed properly as follows:
  2. Defining, requesting and approving the work scope
  3. Hazard Identification, Risk Assessment and Proposed Controls
  4. Approval of Proposed Controls – Hold Point
  5. Implementing Risk Controls
  6. Permission to Proceed/Issuing the PTW – Hold Point
  7. Managing the Work after Issue of PTW
    1. Use of PPE
      1. All personnel will be issued with PPE and instructed to maintain safe working practices always. The HVAC Supervisor will be responsible to confirm that safety procedures are followed.
      1. PPE’s for ear protection (ear muffs, earplugs, etc.) must be used in areas where the noise level is high (above 85 dBA).
      1. Personnel executing the work will always confirm that:
  8. Eye Protectors (goggles /shields /spectacles) are suitable for the work being carried out.
  9. Adequate and appropriate respiratory protection is available while entering confined space.
  10. Appropriate type of hand gloves is used for the activity to be performed.
  1. Hand Tool and Equipment
    1. Construction equipment, machines, tools and measuring instrument to be used in the works will be thoroughly inspected to confirm its working condition prior to used.
    1. Operator will be trained and instructed in the safe use of the equipment.

All power hand tools and Equipment to be inspected and tagged

Md Abu Zaed Khan
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