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| METHOD STATEMENT FOR INSTALLATION TESTING AND COMMISSIONING OF SPLIT AC |
1. PURPOSE
The purpose of this methods statement (MS) is to describe the systematic and quality procedure for the various activities required for the installation, testing & commissioning of wall mounted split AC to ensure that all works are conducted and carried out following the contract specification, approved shop drawings and as per the Manufacturer’s Instruction.
2. SCOPE
This method statement is provided clear and sufficient details for carrying out the Supply and Installation of a [WRITE DOWN CAPACITY HERE] Split Unit.
2.1 Responsibility
It will be the responsibility of the Project Manager and Project Engineer to ensure the availability of coordinated drawings and the required materials as per the project specifications. Split Air Condition System will be commissioned by the experienced foreman/Technician under the supervision of site engineers.
3. LEGISLATION & CODE OF PRACTICE.
All work shall be carried out in accordance mentioned in the project specifications.
4. REFERENCES
• Approved material submittal.
5. DEFINITIONS
PPE Personal Protective Equipment
ITP Inspection & testing Plan
PM Project Manager
PE Project Engineer
QC Quality Control
HSE Health, Safety & Environment
6. RESOURCES
6.1 Materials and their approval:
Split A/C indoor/outdoor units.
6.2 Subcontractor approval:
The work will be executed by [Write down supply/Contractor/company name here].
6.3 Shop drawings:
All Work will be done as per the approved shop drawing.
6.4 Equipment:
- Manifold kit with pressure gauge
- Ammeter.
- Thermometer, Anemometer, DB meter
- Drilling Machine
- Copper tube Cutter
- Gas welding set
- Vacuum pump & tube bender
- Mechanical/Electrical Hand tools
7. SAFETY PRECAUTIONS
- Risk assessment for all activities has been carried out and attached as an annexure, all
- Mandatory control measures should be followed as highlighted in the risk assessment.
- Essential safe access and egress to the Installation area shall be provided.
- Manufacturers’ recommendation & SDS has to be followed for health and safety while using any chemicals.
- Workmen shall wear all appropriate safety personnel protective equipment such as helmets, Coverall clothing, safety shoes, goggles and gloves etc. wherever required.
- If work is at a high level, only approved scaffolding and safety belts should be used
- Sufficient light shall be ensured before the start of the work.
- A safe work permit shall be obtained where required as per the directives of the HSE department
8. INSTALLATION PROCEDURE:
8.1 Decorative type Split Unit
- AC Split units are identified appropriately as per the shop drawings.
- Check and make sure that the Split AC units are inspected for physical damages.
- Make a careful check and confirm the Model Number of the units.
- Carefully shift the Split unit to the location as per the drawing.
- Dimension of supports is marked on the ceiling.
- Holes for piping are drilled on the exact marks and Uni-fix is inserted in the holes.
- Threaded rods are fixed and the check nut is tightened.
- Split units support is inserted carefully through the threaded rods.
- The washer and check nuts are fixed.
- The split unit is checked for proper slope for drainage.
- Accessibility for maintenance is ensured.
- The filter is removed and re-fixed to make sure filters can be removed for cleaning.
- Split AC unit’s drain pipes are connected to the drain point.
8.2 Condensing Unit
- AC‘s Condensing units are identified as per shop drawings appropriately.
- Check and make sure that the Condensing units are inspected for physical damages.
- Check and Confirm the Model Number.
- Condensing units are shifted to location as per drawing.
- Condensing units are placed on the stand.
- Accessibility for maintenance is ensured.
8.3 Refrigerant Piping
- Refrigerant copper coils are selected as per the schedule and as per the approved list of materials.
- Coils Route is marked at the site, as per the approved shop drawings.
- Pre-fabricated supports are fixed onto the structure using the hand tools as per the marking.
- Refrigerant copper coils are cut into the required length using the tube cutter.
- The ends are properly cleaned.
- Insert Insulation (closed-cell electrometric rubber foam thermal insulation as per the approved Material Approval Request (MAR) on Copper Pipe, leave 40-50 mm for brazing the joints.
- Braze all the joints and make sure that all the joints are leak proof in the refrigerant piping network for the AC unit’s installation.
- Complete the insulation at joints.
8.4 Power / Control wiring connection
- The control cable should be approved by the engineer.
- Wires from power isolators are terminated to Air Conditioning Equipment as per the approved wiring diagram.
9. DETAILED TESTING AND COMMISSIONING SEQUENCE AND METHODOLOGY
9.1 Pre-Commissioning Procedure:
a. Make sure that the indoor & outdoor AC unit installation is complete and mechanical completion is appropriately approved
b. Make a careful check for the indoor & outdoor AC units are installed as per the approved shop drawings & manufacturer‘s technical and safety instructions.
c. Check the refrigerant piping installation for the AC unit is complete with all the valves & accessories in line with the approved shop drawings and recommendations
d. Check appropriately for electrical connection between the indoor & outdoor AC units & between the outdoor unit & the power supply system.
e. Make sure that Fan coil alignment is ok as per the design and recommendations.
f. Make sure that the A/C drain point is terminated.
g. Make sure that copper piping is not pinched to avoid any blockage of flow refrigerant.
h. Make sure that all outdoor units are connected with the right indoor unit and properly installed with an anti-vibration mount.
i. Make sure the filter of the indoor unit is clean and dirt free.
j. Make sure that all windows and doors are in close condition.
9.2 Testing & Commissioning Procedure:
9.1.1 Refrigerant Pipe Leak Test
- Connect the vacuum pump to the refrigerant piping circuit and make sure that all the piping network gets vacuumed completely.
- Pressurize the AC Refrigerant piping network by charging Nitrogen up to 450 psi and hold the pressure for a minimum of twenty-four hours. After twenty-four hours check the pressures if it holds 450 psi then flush the system with nitrogen.
9.1.2 Refrigerant Charging
- Once the refrigerant pipes are pressure tested entire piping is flushed with nitrogen gas to remove any foreign material inside the pipes.
- Vacuum the system up to zero psi and wait for 20 -30minuntes then open the hand shut-off valve and release the gas. Equipment/appliance is ready for a test run.
- Run the equipment and check the pressure of refrigerant gas, if required some refrigerant can be topped-up
9.1.3 Commissioning Procedure
- Ensure that the pre-commissioning checks are carried out successfully.
- Ensure refrigerant copper pipes are selected as per the schedule and pressure testing and nitrogen flushing are done.
- After completing cable terminations and refrigerant charging, the equipment is ready to start.
- Switch ON the power isolator of the Outdoor unit and make sure that the DP switch of the indoor unit
- Also, in switch on mode.
- Switch on power, press the on/off button on the wireless remote control to start the operation.
- Press the MODE button to select COOL/HEAT/ FAN to check whether the operation is normal or not.
- The thermostat switch is moved to ON position, Temperature is set at the required set point.
- Starting Current and Running Current is to be recorded.
- Observe the operation of the condensing units for cut and cut out, after completing one cycle of operation, the system is left for continuous operation.
- During running condition rated and Running Ampere of outdoor unit will be checked by Digital meter and recorded in the test sheet
- Connect the manifold kit of the pressure gauge to discharge and suction service ports and record the Suction and Discharge pressure reading in the commissioning checklist.
- After a certain time will check the temperature of the Room by a thermometer whether the cooling Capacity is in satisfactory condition or not.
- Check the indoor & outdoor units are running without any abnormal vibration or noise.
- Measure & record the current & voltage of the compressor.
- Measure & record the ON/OFF coil temperature. Measure & record the total airflow from the unit.
- Record all the reading in the commissioning checklist
10. PPE REQUIREMENTS
As a minimum, the following PPE should be used by staff/labours
- Hard hat
- Safety shoe
- Safety goggles
- Hand gloves
- High visibilities vest
- Dust mask
- Safety harness
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| METHOD STATEMENT FOR INSTALLATION TESTING AND COMMISSIONING OF SPLIT AC |
