When you walk into a large supermarket, you might notice the network of ducts hanging from the ceiling. These ducts are part of the ventilation system, which is crucial for maintaining a comfortable and healthy environment inside the store. The ducts are connected to either air handling units or rooftop units, both of which play a similar role in managing the air quality and temperature inside the supermarket.
Rooftop units are a popular choice for supermarkets because they offer a comprehensive HVAC (Heating, Ventilation, and Air Conditioning) solution. As their name implies, these units are installed on the roof of the supermarket. Depending on the size of the store, you might find several rooftop units working together.
Inside each rooftop unit, a large fan draws fresh air into the system and pushes it into the supermarket. Some units also use this airflow to expel used air from the building. Before the air enters the store, it passes through a filter to remove dust and dirt. Then, it moves through a heat exchanger, where it is either heated or cooled to reach the desired temperature. For heating, the unit might use an electrical heating element, a gas burner, or a heat pump. For cooling, it could employ a split air conditioning unit or a heat pump.
Air handling units function similarly to rooftop units but are generally larger and located indoors. These units also filter, heat, cool, and sometimes humidify the air. However, the heating and cooling in air handling units are typically provided by external chillers or boilers. To maintain the building’s pressure and remove used air, an exhaust air handling unit is often used. If the returning air meets specific CO2, humidity, and temperature criteria, some of it can be recirculated to reduce the energy needed for heating or cooling.
In addition to the main ventilation systems, you might notice fan coil units in large stores. These are smaller units connected to short ductwork runs. A fan coil unit contains a fan with a small motor, a filter, and one or two heat exchangers. These units help circulate air within specific areas of the building and provide additional heating or cooling as needed. They also assist in distributing fresh air throughout the store. The heat exchangers in fan coil units can be connected to a heat pump, VRF (Variable Refrigerant Flow) system, split AC, chiller, or boiler.
We’ve explored the basics of air handling units, rooftop units, and fan coil units in this article. For a deeper understanding, consider watching our previous videos on these topics. To continue your learning journey, check out one of the recommended videos on screen now. Don’t forget to like, subscribe, and follow us on Facebook, Instagram, and LinkedIn. Visit engineeringmindset.com for more educational content.
Imagine you are an HVAC engineer tasked with designing a ventilation system for a new supermarket. Create a detailed plan that includes the placement and type of units (rooftop, air handling, and fan coil units) you would use. Consider factors such as store size, climate, and energy efficiency. Present your design to the class, explaining your choices and how they contribute to maintaining air quality and comfort.
Research a real-world supermarket and analyze its ventilation system. Identify the types of units used and evaluate their effectiveness in terms of air quality, energy consumption, and customer comfort. Prepare a report discussing your findings and suggest any improvements that could be made to enhance the system’s performance.
Participate in an interactive simulation where you can adjust different parameters of a supermarket’s ventilation system, such as fan speed, temperature settings, and air exchange rates. Observe how these changes affect the indoor environment and energy usage. Reflect on the balance between maintaining comfort and optimizing energy efficiency.
Divide into groups and engage in a debate on the advantages and disadvantages of rooftop units versus air handling units for supermarket ventilation. Consider aspects such as installation costs, maintenance, energy efficiency, and environmental impact. Conclude with a class discussion to determine which system might be more suitable under different circumstances.
Organize a field trip to a local supermarket to observe its ventilation system in action. Pay attention to the placement and operation of the units. After the visit, write a reflection on how the observed system aligns with the concepts discussed in the article and any insights gained from seeing the system in a real-world setting.
In many large supermarkets, you’ll see the ductwork suspended from the ceiling. The ducts come from either air handling units or rooftop units, both of which serve a similar role. Rooftop units are more common in supermarkets because they are an all-in-one HVAC solution. As the name suggests, rooftop units are located on the roof of the supermarket, and you’ll usually find multiple units depending on the size of the store.
Inside the unit is a large fan that pulls fresh air into the unit and pushes it into the building. Some units use this pushing force to also expel the used air out of the building. The air passes through a filter to remove any dust and dirt, and then it goes through a heat exchanger where it is heated or cooled to meet the required conditions. The rooftop unit uses either an electrical heating element, a gas burner, or a heat pump for heating. For cooling, the unit will use either a split air conditioning unit or a heat pump.
The other unit we mentioned is the air handling unit, which works in a very similar way, although these are usually much larger and typically housed indoors. These units also filter, heat, cool, and humidify the air, although the heating and cooling are provided by remotely connected chillers or boilers. There is usually also an exhaust air handling unit to maintain pressure in the building and extract used air. If the returning air is within certain limits of CO2, humidity, and temperature, some of it can be recirculated to reduce the heating or cooling load.
If you look up at the ceiling in large stores, you might see a large box connected to a short run of ductwork. This box is called a fan coil unit. Inside the fan coil unit is a fan with a small motor, a filter, and one or two heat exchangers. The fan coil circulates air locally within the building and supplements the heating or cooling as needed. They also help distribute fresh air within the building. The fan coil units can provide heating and/or cooling, and the heat exchangers will be connected to either a heat pump, VRF, split AC, chiller, or boiler.
We’ve covered air handling units, rooftop units, and fan coils in detail in our previous videos, so do check those out.
That’s it for this video! To continue your learning, check out one of the videos on screen now, and I’ll catch you there for the next lesson. Don’t forget to like, subscribe, and follow us on Facebook, Instagram, LinkedIn, as well as visit engineeringmindset.com.
Ventilation – The process of supplying fresh air to an enclosed space and removing stale air. – Proper ventilation in the laboratory ensures that harmful fumes are efficiently expelled and fresh air is circulated.
Ducts – Pipes or channels that transport air, gas, or liquid from one location to another. – The HVAC system in the building uses a series of ducts to distribute conditioned air throughout the rooms.
Air – The invisible gaseous substance surrounding the earth, a mixture mainly of oxygen and nitrogen. – Engineers must consider the properties of air when designing aerodynamic vehicles.
Units – Standardized quantities used to measure physical properties such as length, mass, and temperature. – In thermodynamics, temperature is often measured in Kelvin units.
Heating – The process of raising the temperature of a space or substance. – The heating system in the building is designed to maintain a comfortable indoor climate during winter.
Cooling – The process of lowering the temperature of a space or substance. – The cooling mechanism in the reactor prevents the core from overheating.
Temperature – A measure of the average kinetic energy of the particles in a substance, indicating how hot or cold it is. – Accurate temperature control is crucial in chemical reactions to ensure desired outcomes.
Filter – A device or material that removes impurities or particles from a fluid or air. – The air filter in the ventilation system needs regular maintenance to ensure optimal performance.
Exchanger – A device used to transfer heat between two or more fluids without mixing them. – The heat exchanger in the engine improves efficiency by transferring excess heat to the coolant.
Energy – The capacity to do work or produce change, often measured in joules or calories. – Renewable energy sources, such as solar and wind, are becoming increasingly important in sustainable engineering practices.
