The purpose of this procedure is to define the step by step method to implement the correct practices for the pre-commissioning & commissioning of “Split Unit” through the guidelines contained herein so as to ensure that the job execution complies with the project requirements and serves the intended function to satisfactory level.
Reference Documents
- Contract Specifications and Approved Shop Drawings
- Approved Material Submittals
- Manufacturer’s Instructions
Tools / Equipment /Testing Instruments
- Digital Multimeter
- Clamp Meter
- Tachometer
- Anemometer
- Flow Hood Kit
- Digital Thermometer
- Psychorometer
Quality Control
- In general, it shall be ensured by Site Engineer that product manufacturer’s recommendations are followed and shall be monitored by Project engineer.
- The Project Engineer shall further oversee the Pre-commissioning and commissioning activity as per the approved method statement for Start-up and Commissioning of Split Units.
- The Split Units shall be tested under direct supervision of manufacturer / local dealer’s representatives.
Split Unit Commissioning Procedure
Mechanical Checks
- Carefully inspect the unit for any physical damages / dents.
- Check and ensure the shipping bolts / clamps are removed.
- Check tightness of all nuts / bolts, screws, fasteners, rubber vibration isolators etc. as applicable
- Check the piping connections as per approved drawings.
- Check the fan rotation freely by hand and the direction of rotations on initial startup.
- Align the Unit in the direction of drain to maintain the gravity slope.
Electrical Checks
- Ensure the connected cables have been tested and verify the test reports.
- Check all terminations are complete and tightened as required.
- Check the cabling / wiring including grounding is completed and dressed neatly for thermostat.
- Ensure all identification and labeling is completed.
- Check the isolator is fixed close to the Split Units for emergency power shut-down.
Start Up and Test Preparation
- Check the line voltage before energizing the power
- Switch ON the power.
- Verify for the proper operation of the Split Units motor.
- Measure the current drawn (amperage) by Split Units and record the same.
- Verify proper operation of the thermostat, supply air temperature.
- Check for any abnormal noise and vibration on startup. Rectify as / if required.
- After about an hour’s operation, check that all nuts / bolts, screws, clamps etc. are tight and secure for external units.
- Record the Split Unit/External Unit name plate data in the commissioning format.
- Record the ampere / voltage drawn by the compressor / fan of the outdoor unit.
- Record the refrigerant pressure of the outdoor unit.
- Ensure it is within the limits as per the Ambient temperature.
- Ensure compliance to the manufacturer’s instruction as applicable.
Health & Safety Requirements
- All safety precautions shall be followed as per the established Project Safety Plan.
- Only experienced and skilled technicians shall be engaged for carrying out Start-up and Commissioning of Split Units.
- Safety Guards shall be in place and secured prior to start-up.
- Cable test reports shall be verified prior to energisation.
- Appropriate Warning signs and tapes shall be placed during start-up and commissioning as required.
- All PPE shall be worn as appropriate according to the nature of the job.
- Work area shall be maintained neat and clean.