PLT and PRV Replacement on a Bespoke A/C Unit

PLT and PRV Replacement on a Bespoke A/C Unit

Job Description: PLT and PRV Replacement on a Bespoke A/C Unit

Area: Southwark Street, London

Issue Identified:  Following a recent maintenance on site, the engineer advised that the circuit 2 was very low on refrigerant and required a pressure leak test. He also advised the pressure relief valves were out of date.

Works carried out:

  • Isolated the unit electrically and mechanically.
  • No refrigerant in system.
  • Pressure tested with OFN (oxygen free nitrogen)
  • Leaks found on 2 schrader valves.
  • Replaced Castel Pressure Relief Valves, 3060/45 27.5 bar, valve cores and filter drier cores.
  • Pressurised to 10bar and pressure tested overnight.
  • Once proved released Oxygen Free Nitrogen (OFN) into atmosphere and evacuated the system to a minimum of 2 Torr.
  • Re-charged with the recovered refrigerant and trim charged with virgin refrigerant.
  • Test ran and re-commissioned.
  • Completed a waste transfer note and handed to on-site representative.
  • Completed an F Gas certificate.
Abbreviations

HVAC – Heating, Ventiliation and Air Conditioning, PLT – Pressure Leak Test,  PRV – Pressure Relief Valve, PPM – Planned Preventative Maintenance, OFN – Oxygen Free Nitrogen, AHU – Air Handling Unit, GWP – Global Warming Potential, VRF – Variable Refrigerant Flow, VRV – Variable Refrigerant Volume, ACU – Air Conditioning Unit, FCU – Fan Coil Unit, AC – Air Conditioning,  HP – High Pressure, LP – Low Pressure

Ref: 1684