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TESTING & COMMISSIONING (T&C) OF HVAC CHILLER

TESTING & COMMISSIONING (T&C) OF HVAC CHILLER



✅ Pre-Commissioning Checks

✔ Verify chiller model, capacity, refrigerant, and installation as per approved drawings.

✔ Check foundation alignment, vibration isolators, and mounting bolts. 

✔ Confirm piping connections (CHW & Condenser Water) — flow direction, supports, flexible joints. 

✔ Ensure valves installed correctly: isolation, balancing, flow switch, drain, vent. 

✔ All electrical connections terminated — proper cable size, breaker, earthing, and isolator. 

✔ Sensor wiring & BMS points connected and tested. 

✔ Insulation completed and cladding sealed (especially outdoors).


Flushing & Cleaning

⇒ Conduct chemical flushing of CHW & condenser lines: 

  •  Use biocide + scale remover. 

  •  Flush till water is clear.

 ⇒ Post-flush: Passivation to protect pipe interiors. 

⇒ Hydrostatic pressure test as per code (usually 1.5x working pressure). 

⇒ Vent all air pockets using manual/auto air vents.


Dry Run / No Load Test

⇒ Power up the panel — check phase sequence, voltage levels, and alarms. 

⇒ Run chilled water pumps (primary/secondary). 

⇒ Confirm flow switch operation (cut-in/cut-out). 

⇒ Run chiller without load: 

  • Compressor starts/stops. 
  • No abnormal vibration/sound. 
  • Monitor electrical readings (Amps, Volts).

❄ Full Load Commissioning

⇒ Start system with actual cooling load (or dummy load if building not ready). 

⇒ Monitor: 

  • CHW Supply & Return Temperature (Target Δ T = 6–8°C)
  •  Condenser In/Out Temperature
  •  Compressor amps and running condition 
  • Refrigerant pressures (low & high side) 
⇒ Check expansion valve response and superheat. 

⇒ Verify auto-cutoff & restart at setpoints (thermostat, overload, flow).


Functional & Safety Tests

⇒ Simulate flow loss — ensure chiller trips. 

⇒ Simulate high/low pressure — verify safety shutdown. 

⇒ Trip power — confirm auto-restart sequence. 

⇒ Test BMS integration: 

  • Start/Stop control 
  • Alarm signals 
  • Temp/Pressure monitoring 
  •  Status feedback

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