NVQ L4 Refrigeration & AC case studies
NVQ L4 Refrigeration & AC · Put your knowledge to work in context.
The NVQ Level 4 in Refrigeration and Air Conditioning is a work-based, competence-assessed qualification for experienced refrigeration and air conditioning engineers who are moving beyond hands-on servicing into roles carrying technical, legal and supervisory responsibility. Unlike a written examination, it is judged mainly on what you can evidence in your own workplace: the systems you have designed and specified, the projects you have planned and run, the commissioning and handover you have signed off, the complex faults you have diagnosed, and the way you supervise and develop others. The NVQ L4 Refrigeration & AC case studies are 5 cases and about 4,094 words.
1R-32 Retrofit in a Basement Plant Room
Your company is replacing a failed R-410A split system in a basement plant room of a city-centre hotel with a 4 kg R-32 (A2L) system. The room is 4.0 m × 3.0 m × 2.6 m, accessed by a single door at the top of three steps, with no permanent mechanical ventilation and no refrigerant detection.
840 words, about 4 min2Handover Under Pressure on a Frozen Store
You are commissioning a new frozen store, 9.5 m × 6 m × 3.2 m, served by two ceiling-mounted unit coolers from one roof-mounted air-cooled condensing unit on R-449A. Design room temperature is −25 °C with product entering at −18 °C; ambient on the day is 29 °C.
767 words, about 4 min3High-Pressure Trips on One of Two Identical Chillers
Two identical air-cooled chillers sit side by side on a roof deck, each with two R-410A circuits (11 kg per circuit) and three vertical-discharge EC condenser fans. A 3 m acoustic screen surrounds the plant and stands 800 mm from the discharge face of chiller 1; a 2.5 m parapet completes the enclosure.
840 words, about 4 min4Three Top-Ups and a Can of Leak Sealer
You manage refrigeration for a distribution centre. Its 210 kW air-cooled chiller holds 95 kg of R-410A and is 12 years old.
795 words, about 4 min5What You Find on Return from a Client Meeting
You supervise a three-person team installing a remote condensing unit and two cold rooms in a shopping centre service yard on a 10-day programme that is already two days behind after a delivery slipped. On day 6 you return from a client meeting at 14:30 to find: the 17-year-old first-year apprentice alone in the plant room with a lit oxy-acetylene torch, brazing the last joint on a liquid line; the condensing unit's high-pressure switch linked out with a croc clip 'to get the case down for the tenant's fit-out'; and no hot-work permit on the board for today.
852 words, about 4 min