NVQ L4 Refrigeration & AC study plan

Compare five system architectures (DX split, VRF, chilled-water fan coil, transcritical CO2, pump-circulated ammonia) against a stated load profile, occupancy pattern and refrigerant charge limit, and justify a selection.

Calculate the cooling and heating load for a small commercial premises, separating sensible from latent gain and documenting every assumption.

Size suction, discharge and liquid lines for two circuits, checking pressure drop, oil-return velocity and riser height limits.

Assemble a specification schedule listing plant, controls, insulation, isolation valves, access space and service clearances for one chosen system.

Produce a design review checklist that a second person could use to challenge the load figures, pipe sizing and equipment selection.

Build a symptom-to-cause fault matrix covering at least ten symptom classes (high superheat, low superheat, high discharge temperature, low suction pressure, fluctuating suction pressure, icing at the metering device, repeated high-pressure trips and similar), with the confirming test for each cause.

Interpret a set of pressure-enthalpy and temperature-pressure readings to place a fault on the cycle and state the next measurement to take.

Write a twelve-month planned preventive maintenance schedule for a refrigeration plant, giving task frequency, acceptance criteria and the record produced for each task.

Draft a repair method statement that sequences isolation, refrigerant recovery, safe isolation of electrical supplies, pressure testing and reinstatement.

Explain how to distinguish a control or sensor fault from a genuine refrigeration fault before any parts are ordered.

Complete three risk assessments covering hot work and brazing, refrigerant charging and recovery, and work on rooftop plant at height, each with residual risk rating after controls.

Identify the specific hazards of the refrigerants in use (asphyxiation in plant rooms, toxicity, A2L flammability, stored pressure, cold burns) and state the engineering and procedural controls and PPE for each.

Produce a permit-to-work and isolation sequence for a task that needs both electrical and refrigerant isolation.

Describe the duty-of-care route for waste refrigerant, contaminated oil and scrap cylinders, including labelling, storage and transfer documentation.

Write an environmental incident response for a refrigerant release, covering evacuation, ventilation, notification and clean-up.

Build a programme for a four-week installation showing activity sequence, dependencies, lead times and inspection hold points.

Estimate labour hours and material quantities from a drawing and equipment schedule, then convert them into a costed resource plan.

Plan the delivery, lifting and positioning of outdoor plant, including access route, lifting plan, permits and protection of the building fabric.

Set up a progress-tracking method with a short-interval plan and a snag and defect register that links each item to an owner and a date.

Identify the top five project risks for the installation and state a mitigation and a contingency for each.

Write commissioning checklists for strength and tightness testing with oxygen-free nitrogen, evacuation and vacuum decay, and charging by weight, each with pass criteria.

Verify electrical and control safety functions: interlocks, phase rotation, compressor and pump rotation, alarm and trip testing, and set-point verification.

Produce a handover pack index covering as-built drawings, O&M manuals, refrigerant record, test certificates, training record and warranty documentation.

Define acceptance criteria for airflow balancing, temperature difference and controls operation, and describe how deviations are recorded and closed out.

Explain how to demonstrate a system to the client's operating staff and what competence evidence the handover should capture.

Map the operator and technician obligations for stationary refrigeration equipment: competence and certification, leak checking, record keeping, labelling, recovery and the phase-down of high-GWP refrigerants.

Calculate the CO2-equivalent charge of five example systems from refrigerant mass and GWP, then determine the applicable leak-check frequency and record-keeping requirement for each.

Design a refrigerant register and cylinder-tracking log that would survive an audit, including recovered, recycled, reclaimed and virgin quantities.

Write the procedure for recovery, recycling, reclamation and disposal, stating which practices are prohibited and what evidence should be retained.

Evaluate how refrigerant choice at design stage affects future compliance cost, and document the trade-off in a short technical note.

Prepare and deliver a toolbox talk on a safety or quality topic, with a briefing sheet and an attendance and understanding check.

Build a skills matrix for a six-person team against the tasks the work requires, and record two development actions per person with a review date.

Design a quality inspection checklist and a defect register that uses root-cause categories rather than free text.

Apply a plan-do-check-act cycle to one recurring defect, recording the baseline measure, the countermeasure and the post-change result.

Describe how to give corrective feedback on a poor-quality work practice so that the standard is re-established without demotivating the operative.

Sit a full-length timed mock examination under exam conditions and mark it against the criteria.

Re-work every question answered incorrectly, writing the correct reasoning in your own words and citing the source of the fact.

Revisit the three weakest domains identified by the mock and redo one goal from each of those weeks.

Rehearse answering scenario questions aloud in the structure: identify the hazard or fault, state the control or test, state the evidence that proves it.

Confirm that every portfolio deliverable from weeks one to seven is complete, dated and cross-referenced to its domain.