Equipo de frío que no enfría

A 90-minute, 4-round basic Express simulation for Spanish vocational training (Formacion Profesional), module 0040 Montaje y mantenimiento de equipos de refrigeracion comercial of the Tecnico en Instalaciones Frigorificas y de Climatizacion (Real Decreto 1793/2010), with module 0135 Mantenimiento de instalaciones frigorificas y de climatizacion of the Tecnico Superior en Mantenimiento de Instalaciones Termicas y de Fluidos (Real Decreto 220/2008).

The learner is Nerea Arrontegui, a newly qualified refrigeration technician on the callouts for units that do not cool at a fictional refrigeration company, Frigoservicios Valdecaraza, between October 2027 and September 2028.

Four situations set the company's course: a dairy display case above its temperature and a propane freezer island, and how the technician enters and makes the unit safe before it is opened (the product protected, the power off, the refrigerant read and, if flammable, the area checked and ventilated) and how the alarm is read (against the temperature record and the history); a cold room that short-cycles, and how the circuit is diagnosed (the pressures, the superheat and the subcooling measured together against the maker's values) and how the leaks are looked for (a suitable detector before any charge is added); a cracked pipe and a high-pressure trip, and how the circuit is opened and repaired (the refrigerant recovered, brazing with nitrogen, the vacuum checked, the charge by weight) and how the unit is left in service (a complete check, the unit not left in service if any point fails); and the summer review of how each callout is reported (the readings, the kilos of refrigerant, the installation's logbook) and closed (a call at thirty days, repeated faults reviewed).

Superheat and subcooling together point to the cause.

Scored on the callouts diagnosed right first time, the cost of the callouts, the product lost per callout and the refrigerant emitted in tonnes of CO2 equivalent; training-level decision practice that complements the module's supervised practical work, the company's procedures, the makers' manuals and the certification to handle fluorinated gases, with no pressure, temperature, superheat, charge or procedure given.

Three critical errors cap the round at 40: brazing a propane unit without checking or ventilating, venting the refrigerant to the atmosphere (Regulation (EU) 2024/573), and bridging the high-pressure switch so that the compressor keeps running (Ley 31/1995, article 29.2.3). Spanish primary, English parity.

An introductory simulation that assumes no prior knowledge of the subject, designed for undergraduate courses. It also works in vocational and high-school programmes and in onboarding sessions.