With air curtains supplier in India, Selecting a vendor is one of the most crucial tasks before selecting an air curtain. A reliable vendor will understand your needs and help you choose the air curtain that is best suited to your requirements. There are various important factors listed below that you must consider before selecting your vendor:
- Manufacturer: You should know the original source i.e. from where your vendor procures the machines. The manufacturer must be a reputed one in the field and enjoy great goodwill in the market.
- Experience: To a great extent, the experience of the vendor decides his reliability. Better experience implies a better understanding and knowledge of market conditions and customer requirements. Therefore, it becomes imperative to analyze the experience of the vendor.
- A number of installations: Choose the vendor who has already served for a number of years. Get to know the number of installations done by them within the country and around the world (if any). A large number of installations would imply better knowledge and a better understanding of the field.
- Technically Equipped: Their production unit should be technically advanced in terms of working and delivery. It will provide a better breakthrough in the competitive market. The vendor should be able to guide you on various kinds of flow patterns and workability and should be able to customize a solution whenever required.
- Warranty and part Availability: Many vendors commit to a warranty that is beyond their scope. As an international standard, a manufacturer should be able to provide support for all the parts and make them available for a minimum tenure of 10 years. Generally, traders overcommit and shed their responsibility when parts are needed.
What should be the Right Velocity AsPer AMCA/NSF Guidelines
Everyone in the industry struggles with the above question and many times, engineers out of their experience or some thought specify velocities at different points, either on top of the door or on the floor, etc.
The Air curtain Manual by AMCA Specifies the right velocity parameters. The same is mentioned in NSF Guidelines also.
The velocity specifications as mentioned in AMCA Publication, 222-08 Application manual for Air Curtains, are as follows:
Application Manual for Air Curtains; Section 8.6.1.2
8.6.1.2 ANSI/NSF37- Air Curtains for Entranceways in food and food service establishments. The NSF standard establishes criteria for ACU air performance, construction, design, and material type. An ACU construction that complies with this standard is considered by the food service industry to provide effective flying insect protection to an entryway by deterring flying insects from entering through the opening or nesting in the ACU. These criteria can be summarized into basic principles that are intended to create a clean and healthy environment.
- Laboratory Methods of Testing Air Curtain Units for Aerodynamic Performance Rating: This AMCA standard defines the test methods that can be used to generate data for the typical types of air curtains performance. This data can then be used to compare different models for aerodynamic performance. Note that the data generated from the tests described in the standard does not define an ACU’s relative effectiveness.
If the data is measured and generated from an AMCA accredited laboratory, the product can be licensed to bear the AMCA seal (if applied for) under AMCA 211, Certified Rating Program- Product Rating Manual for Fan Air Performance. The AMCA Seal represents the fact that the ACU has been independently tested by a third party, adding credibility to manufacturer ratings.
The performance data generated, as defined by ANSI/AMCA 220 and simplified here, are:
- Average Outlet Velocity- The mathematical derivation of a velocity flow rate by dividing the air volume flow rate by the air curtain discharge area. This value should be used with outlet velocity uniformity to compare different ACUs.
- Velocity Projection- The average of the peak velocities measured along the ACU discharge nozzle at predetermined widths at specified distances away from the ACU. These values can also be used to determine velocity uniformity at said specified distance.
- Outlet Velocity Uniformity- This is a measure of the consistency of the discharge velocities across the ACU width expressed in a percentage determined by a standard deviation method.
- Airflow Rate- Physically measured by a recognized air volume test chamber using ANSI/AMCA 210, Laboratory Methods of Testing Fans for Certified Aerodynamic Performance Rating.
- Power Rating– This is the electrical power actually consumed by the entire unit(in KW) during the Air Volume Flow Rate; not to be confused with the mechanical energy equivalent to the unit horsepower.
- Air Curtains Entranceways in Food and Food Service Establishments: The NSF standard establishes criteria for ACU air performance, construction, design, and material type. An ACU construction that complies with this standard is considered by the food service industry to provide effective flying insect protection to an entryway by deterring flying insects from entering through the opening or nesting in the ACU.
These criteria can be summarized into basic principles that are intended to create a clean and healthy environment. The air performance defined in this standard is geared toward protection from flying insects.
The opening types are defined by three categories:
- Customer Entryway
- Service Entryway
- Drive through Window
Each type has its own minimum performance requirement.
- Customer Entryway: The Customer Entryway test requires a maximum mounting height declaration and a minimum air velocity of 3.05 m/s (600fpm). Velocities are measured within 200mm (8 in.) deep by ACU nozzle width wide area broken into 50mm*150 mm (2in.*6in.) grids, 0.9m (3ft) from the floor.
- Service Entryway: The service entryway test requires a maximum mounting height declaration and a minimum air velocity of 8.15m/s (1600 fpm). Velocities are measured within a 75mm (3in.) deep by ACU nozzle width wide area broken into 75mm*150mm(3in.* 6in.) grids, 0.9m(3ft) from the floor.
- Drive-through Window: The drive-through Window test requires only a minimum air velocity of 3.05 m/s (600 fpm), 1/3 the distance of the vertical opening above the service window countertop. Velocities are measured within a 200mm (8 in.) deep by ACU nozzle width wide area broken into 50mm * 150 mm (2 in.*6 in.) grids.
The design and construction requirements are intended to prevent the nesting of vermin, the accumulation of dirt, debris, and moisture; and to provide accessibility for servicing, cleaning, and inspection.
The material requirements are intended to ensure that the equipment is resistant to penetration from vermin and wear with the respect to food safety (i.e., the effect of food, heat, refrigerants, cleaning, and sanitizing compounds).
Lastly, ACU units can be tested, certified, and listed to standard ANSI/NSF 37 by nationally recognized testing laboratories and certifying bodies that have a food service program. Some of these agencies include NSF and the corresponding NSF Mark, UL.