The portable air conditioners launched in the United States in 1984 for high ambient applications changed the way spaces, people, equipment and processes are cooled in the industrial settings. Cooling became more efficient for small areas and small level industrial applications. Portable AC designs were already tested in other countries for more than a decade. It led to developing the ANSI/ASHRAE 128 Standard, which is used to rate portable unitary spot ACs.
Commercial air conditioners are complying with this standard to help cool people, equipment, space and processes without generating excessive cooling temperature, airflow rate or air volume. It prevents many health issues. A variety of AC models under this category are available for small to medium level requirements. Smaller units can be used to cool one or a few persons. Larger HVAC units in the range of 3-5 tons can be used to cool a work or assembly area.
It is well known that health and safety standards at the workplace improve a lot when it remains cool and dry. It increases productivity, and the staff does not feel tired. For example, workers cleaning the storage tanks or vessels in an industrial setting do not need frequent exhaustion breaks when their work area remains cool.
These ACs improve the effectiveness of cooling. The plant or workplace areas can be cooled more efficiently. The portable air conditioners are available in 115V, 208-230V, and 460V models for industrial applications. These portable units have wheels so they can be moved easily from one place to another. The strong metal cabinetry, a refrigeration system, and the airflow nozzles that can be moved in the required direction are some of its features that make it perfect for industrial applications.
The cool environment at the workplace protects employees, equipment and processes from the damaging effects of a hot environment. These ACs can work even when the ambient temperature goes up to 115F. Its spot cooling feature is highly useful for industrial processes. It protects sensitive products like electronic chips, rubber items, glass parts, metal bars and plastic items. It can be used to cure products precisely by increasing or decreasing its flow rate. It also removes unwanted moisture. The controlled environment helps preserve the product’s shape and integrity. Deformity in products coming out of a process line can be avoided. It leads to increased productivity and more products can be manufactured.
Equipment and many other assets used in an industrial setting benefit from a cool and temperature-controlled environment. Their life increases and they operate more reliably. For example, portable air conditioners can keep cool electrical control panels during the summer months when heat can damage these items. Process control rooms, nuclear plant areas, and electric furnace operations at some places need spot cooling. A portable HVAC increases the reliability and life of numeric control machines.
128 Standard Compliant Design
Commercial AC units complying with this standard have been tested for cooling at 95F ambient temperature and 60% relative humidity at their evaporator coils and condenser. AC’s complying with this standard must have 270 CFM volume and 33 FPS air velocity to generate 19.8F delta-T cooling environment. The delta-T indicates the real temperature difference between an evaporator section’s airflow and the air released from the nozzles or grilles of the AC.
Using Spot Cooling ACs to Cool People
As one air conditioning company told us, “Sometimes it is not only about the AC capacity but also about the airflow volume and the space temperature. Proper and effective cooling of people in industrial settings depends on several factors.” The temperature should be in the range of 85-113F. Humidity, air volume, temperature difference, the velocity of airflow and activity levels are some other factors that affect the cooling quality. For example, a person performing a high-level activity will need at least 260-290 CFM airflow with a velocity of 26-30 FPS at a temperature difference of 16-20F in an area that has 105F ambient temperature. Different standards and specifications are needed for places with lower activity levels and higher ambient temperatures.
Basic specifications help choose the right portable air conditioner for places with high work activity level and temperature. There are five basic levels to cover the activity levels and temperature going up to 113F with relative humidity up to 60%.
Process Spot Cooling
More and more industrial centers are now using portable air conditioners for process cooling because it is effective and economical. It is suitable for cooling areas with extrusion machines, injection molding, electronic products, edible items and vessels. The desired cooling is achieved for these applications using portable AC parameters and wind-chill physics.
Heat in objects is lost from inside out. The heat is removed faster from the top of the object if the core heat is transferred quickly from the center to the outside layers. It creates a faster flow rate, fewer rejects and lower costs. Focused airflow from portable spot coolers in the range of 270-1680 CFM and 13-20F supply temperature drop can be achieved. It works better than the industrial fans.
Equipment Spot Cooling
The spot cooling device selected for this purpose depends on the type of equipment that requires cooling. It can be a power panel, NC machine, switching control, testing device, control room component, or computer operating in a hostile or high ambient environment.
The interior temperature of equipment can be reduced to the desired level by focusing on low-temperature airflow precisely. The equipment cabinetry can be cooled faster by directing an AC’s airflow around it. Cool air can be passed through the air grilles of the cabinet.
Flanges can be attached to the outside panel of an equipment cabinet. The flanges are attached to the flexible duct of the portable AC with 270-1680 CFM airflow volume. For example, the airflow of a portable AC can be used to remove the excess heat of a transformer. The heat can be taken out through the cooling slits. The cooling rate can be increased by directing the cool air of the AC through the ducts.
Conclusion
Portable air conditioners are beneficial in cooling different levels of hot spots. These units are now used extensively for spot cooling the people, equipment and processes. Problem area should be evaluated properly to determine the right type, size and capacity of portable HVAC.