• Comfort and Productivity: AC provides a comfortable indoor environment, which is crucial during hot weather. By regulating the temperature, it helps people stay focused and productive.

• Health Benefits:

  • Prevents Heat-Related Illnesses: AC is a major protective factor against heatstroke and dehydration, especially for vulnerable populations like the old people, children, and people with poor health conditions.

  • Improved Air Quality: Many AC units have filters that reduce allergens, dust, pollen, and other pollutants in the air, which can be beneficial for people with allergies or asthma.

  • Reduces Humidity and Prevents Mold: AC systems reduce humidity levels, which helps to prevent the growth of mold which can be harmful to health.

• Protects Electronics and Appliances: Computers, servers, and other electronic devices can overheat in high temperatures. AC helps to keep them at a stable temperature, extending their lifespan.

  
  

High Electricity Usage: AC units consume a significant amount of electricity, which can lead to higher utility bills.

Greenhouse Gas Emissions: The electricity used to power AC units often comes from fossil fuels, contributing to carbon emissions.

Refrigerant Chemicals: AC units use refrigerants that can contribute to global warming if they leak or are not disposed of properly.

Health Problems:

Dry Air: AC systems remove moisture from the air, which can lead to dry skin, eyes, and throat.

Respiratory Issues: If not properly maintained, AC units can become breeding grounds for bacteria, mold, and fungi. These can be circulated in the air, causing respiratory problems and allergic reactions.

Sudden Temperature Changes: Moving from a hot outdoor environment to a cold, air-conditioned space can be a shock to the body, leading to headaches, muscle stiffness, and other discomforts.

The Laws of Thermodynamics:

Zeroth Law - if two bodies are in thermal equilibrium with a third one, then they are also in equilibrium with each other. In simple words: If a thermometer shows the same temperature for two objects, it means they have the same temperature. Example: If the thermometer reads 25 °C in both glasses of water, the two waters are at the same temperature.

First Law - Energy cannot be created or destroyed, only transformed. In simple words: the heat that enters or leaves a system is transformed into work or changes in internal energy, but it never disappears. Example: the heat from a stove turns into increased temperature of the water in the pot.

Third Law of Thermodynamics: it is impossible to reach absolute zero (0 Kelvin = –273.15 °C). In simple words: particles can never completely stop moving; we can only get very close to that temperature. Example: scientists can reach temperatures very close to absolute zero in laboratories, but never exactly 0 K.

Compressor: Pressurizes the refrigerant gas, raising its temperature and pressure.

Condenser coils: Located outside or at the back, these coils allow the hot refrigerant gas to release heat to the surrounding air and condense into a high-pressure liquid.

Expansion valve or capillary tube: Reduces the pressure of the liquid refrigerant, causing its temperature to drop before entering the evaporator.

Evaporator coils: Located inside the refrigerator compartment, these coils absorb heat from the interior, evaporating the refrigerant back into a gas.

Refrigerant: A fluid that circulates through the system, absorbing and releasing heat as it changes phase between liquid and gas.

Condensation: In the condenser coils, the refrigerant releases heat to the environment (usually air or water), and condenses into a high-pressure liquid. This process removes heat absorbed earlier from the refrigerator’s interior.

Expansion: The high-pressure liquid refrigerant passes through an expansion valve or capillary tube, reducing its pressure. This sudden pressure drop causes the refrigerant to cool significantly.

Evaporation: The cold, low-pressure refrigerant enters the evaporator coils inside the refrigerator. It absorbs heat from the food and air in the compartment, evaporates, and turns back into a low-pressure gas. This heat absorption is what cools the interior.

The process starts in the burner, where fuel and air mix and ignite thanks to the ignition system. The flame burns inside the combustion chamber, which resists high temperatures.

Heat is transferred to water through the heat exchanger, without mixing gases and water.

The flue gas exhaust system or chimney removes fumes. In condensing boilers, a condensate drain removes acidic water.

Fuel arrives through the fuel supply system, which controls flow and pressure. The control unit manages all functions and safety.

The circulation pump moves hot water.

Safety is ensured by the safety thermostat, pressure relief valve, and expansion vessel.

The temperature sensor and pressure gauge help monitor the system.

The air intake system provides the right air for combustion and reduces pollution.

The air is heated or cooled by the heating coil and cooling coil. If the air is too dry, the humidifier adds moisture; if it is too humid, the dehumidifier removes it. Any water produced is collected in the drain pan. To reduce noise, the AHU includes a silencer.

After treatment, the air leaves through the supply air outlet, while used air exits from the exhaust air outlet. Sensors and the control system check temperature, humidity, and airflow to keep the unit safe and efficient.

1. Boilers

-Gas boilers (methane, LPG)

-Oil‑fired boilers

-Biomass boilers (pellet, wood, wood chips)

-Condensing boilers

2. Radiator systems

-Cast‑iron, steel, and aluminum radiators

-Connections, valves, lockshield valves, hydraulic balancing

3. Hydronic underfloor / wall / ceiling heating

-Hydronic radiant panels

-Manifolds, circulation pumps, mixing valves

-Regulation of supply temperatures

-Geothermal

-Connection to hydronic circuits and storage tanks

4. Solar thermal

-Solar thermal collectors

-Storage tanks, heat exchangers, circulation pumps

-Integration with a boiler or heat pump

1) drill: used to make holes in walls or panels to fix pipes, brackets, or electrical boxes;

2) Pliers:Useful to hold and bend wires, thin pipes, or small components. They also help tighten or loosen parts.

3) Hacksaw: Used to cut metal, such as copper pipes or steel brackets.

4) screwer: Used to insert or remove screws, for example to fix plates, boxes, or covers.

5) Soldering iron + solder: Used to join electrical wires or small metal parts by melting solder.

6) Spanner + nut: Used to tighten or loosen nuts and bolts, often found in pipe fittings.

7) Tape measure: Useful to measure pipe lengths, distances between fixing points, or installation spaces.

8) Safety goggles: Protect the eyes from dust, sparks, or debris during work.

During my training, I learned how to help with the installation and maintenance of heating, cooling, and plumbing systems, and to support technicians during basic troubleshooting tasks.

Through my work experiences, I have developed good teamwork and communication skills, and I can work well with colleagues and follow instructions carefully. I pay attention to safety rules and quality standards.

I consider myself a reliable and motivated person, willing to learn and improve my technical skills.

Vorrei però dirvi una cosa importante. Non siete un voto. Non siete il numero scritto su una verifica, su una pagella o sul registro elettronico. Quel numero può raccontare come è andata una prova in un determinato giorno, ma non può raccontare chi siete davvero.

Voi siete molto di più. Siete i sacrifici fatti per arrivare a scuola ogni mattina. Siete le mani che hanno imparato a usare gli strumenti con precisione. Siete gli errori che vi hanno insegnato qualcosa. Siete le volte in cui avete ricominciato dopo una delusione. Siete la capacità di collaborare con i compagni, di trovare soluzioni ai problemi, di mettervi in gioco anche quando non vi sentivate pronti.

Nel vostro futuro lavorativo nessuno vi chiederà soltanto che voto avete preso. Ciò che farà la differenza sarà la vostra serietà, la vostra affidabilità, la voglia di imparare ancora, la capacità di assumervi responsabilità e di affrontare le difficoltà con determinazione.

Il mondo del lavoro ha bisogno di tecnici competenti, ma soprattutto di persone autentiche. Persone che sappiano rispettare gli altri, lavorare in squadra, mantenere la parola data e continuare a crescere professionalmente e umanamente.

Per questo vi invito a guardare ai risultati scolastici con equilibrio: siate orgogliosi dei successi e imparate dagli insuccessi. Un errore non definisce il vostro valore, così come un voto non esaurisce tutto ciò che siete.

Portate con voi ciò che avete costruito in questi anni: le competenze, certamente, ma anche il carattere, la resilienza, il coraggio di affrontare le sfide in maniera positiva e la consapevolezza che ogni percorso importante è fatto di tentativi, cadute e ripartenze.

Qualunque strada sceglierete dopo l’esame, ricordatevi sempre che il vostro valore non si misura con un numero, ma con la persona che decidete di essere ogni giorno. Con la vostra serietà. 

Vi auguro di avere fiducia nelle vostre capacità, di non smettere mai di imparare e di affrontare il futuro con la stessa forza con cui siete arrivati fin qui.