SHOULD THE AIR CURTAIN BE MOUNTED INSIDE OR OUTSIDE THE DOORWAY?
Generally, air curtains will operate with equal efficiency, regardless of which side of the doorway it is mounted on. However, there are certain exceptions, as follows:
Air Curtains should be installed on the warmer side.
Inside Installations are done in case of heated Air Curtains when we do not want the cold breeze to come in and want to circulate the inside hot air.
Outside installation is required when used over freezer doors because when mounted inside, the fans tend to gather moisture and freeze, eventually forming a snowball around the fan, causing it to lose operational efficiency.
Air Curtains installed outside offer a better prevention to mosquitoes and flies.
DO MITZVAH AIR CURTAINS REQUIRE A COVER WHEN MOUNTED OUTSIDE?
No, they generally do not require any cover when installed outside, until and unless there is a probability of Direct rain or chances of water ingress in the machine. There ia standard accessory which can be ordered to make a rain hood or protect the machine.
IS THERE ANY DIFFERENCE IN THE SOUND LEVEL IF A mitzvah AIR CURTAIN IS INSTALLED OUTSIDE OR INSIDE?
No, there is no Difference in sound level of the machines when installed inside or Outside, but since air curtains circulate a huge volume of air, in very quiet conditions it may be disturbing. Hence installing them outside gives a better protection and even affects the feel of sound level.
HOW FAR ABOVE THE DOORWAY HEADER SHOULD THE AIR CURTAIN BE MOUNTED?
We should install air curtains just above the door header or to a maximum of half to two inches. The closer to the top of the door opening, the more effective the air curtain will be. Extended mounting brackets are available in various lengths so the air curtain can be mounted to clear an obstruction.
In no way Air Curtains should be taken more than two inches above the Door header, generally done in case of of fixed glass above the Door, people tend to put it above the fixed glass, in such conditions air curtain efficiency will be severely affected.
IF THERE IS AN OBSTRUCTION OVER THE DOORWAY, HOW FAR AWAY FROM THE WALL CAN THE AIR CURTAIN BE INSTALLED AND STILL FUNCTION EFFECTIVELY?
Not more than eight inches for refrigeration and fourteen inches for insects. To seal off the ends, twelve to eighteen inch panels made of sheet metal, plastic strips or plywood can be installed on each side of door opening to improve the efficiency of the air curtain. Sometimes the mitzvah air curtain air outlet nozzle may be installed between the obstruction and the wall. Precaution is necessary to prevent the obstruction from deflecting the flow of air.
WHEN MORE THAN ONE AIR CURTAIN IS INSTALLED OVER A DOORWAY, HOW CLOSE TOGETHER SHOULD THEY BE MOUNTED?
When Door opening is wider than the units, they should be mounted next to each other. The spacing gap upto 3 inch is acceptable between the Units.
WHAT HAPPENS IF THE AIR CURTAIN IS MUCH SMALLER THAN THE DOOR-WIDTH OPENING?
This should never be installed in such conditions. When the air curtain starts it makes a high velocity stream which creates a turbulence and thus creating negative draft along the sides of the curtain wall, and if the door opening is more than the width of the machine, this secondary motion will mix both the airs at a much faster rate.
SHOULD WE TAKE AIR CURTAIN MORE THAN THE DOOR-WIDTH OPENING?
We should not take a Air curtain, more than the Door width, though technically it will not effect but commercially will not be a right decision. Air curtain length should be more or less equal to the width of the door.
WHEN WOULD A VERTICAL MOUNT BE FEASIBLE?
When installation is not possible over the top of the doorway, the mitzvah air curtain may be side-mounted on both ends of the door. As per the guidelines of AMCA, in case of side installation either the air curtains should be installed on both the sides or in a zigzag pattern to cover the entire length of the door.
Yes, the same Air Curtains can be vertically mounted.
HOW DOES THE AIR CURTAIN MOUNT OVER A LARGE WAREHOUSE ROLL-UP DOOR?
Generally doors roll up on the outer side of the Doorway and we even install air curtain on the outside wall and hence it becomes a challenge. Special brackets can be fabricated for the same, customers can get the drawings from the website or take a Autocad or PDF drawings from the customer care executive by calling +91 9211092110, mitzvah can also also supply the brackets at a nominal charge.
WHEN THERE IS NO SPACE ABOVE THE DOOR, WHERE SHOULD THE AIR CURTAIN BE MOUNTED?
Air Curtains can be mounted above the Door by cutting a false roof, and you should consider following points while doing the same. First, the trap door should be provided for service and secondly there should be a space to suck the air.
CAN THE DOOR ITSELF BE REMOVED AND THE AIR CURTAIN ALLOWED TO OPERATE CONTINUOUSLY, 24X7 ?
Yes, with Air Curtains you can follow a OPEN DOOR POLICY, for your outlet. Air curtains when rightly installed and directional louver set at a right angle, can give a continuous thermal protection, and can be installed without a door. mitzvah air curtains are built to run 24X7 continuously.
HOW DO YOU CLEAR EXISTING LINES AND TRACKS OVER A DOORWAY?
mitzvah provides a variety of optional mounting hardware accessories. Side extension plates are available to further extend the outboard mounting holes. These plates are available in various sizes up to a nine inch extensions for both ends of the air curtain. Adjustable mounting brackets and extended wall mount brackets for drum type roll-up doors are also available. These type of brackets are used when the air curtain needs to be mounted some distances away from the wall. The brackets are also available for mounting on the glass and special brackets to connect the two machines together.Please consult customer care on +91 92110 92110, for details.
HOW DO YOU MOUNT A AIR CURTAIN OVER A CONVEYOR TYPE PRODUCTION LINES WHERE THE TRACK THAT COMES OUT THROUGH THE CENTER OF THE DOOR OPENING?
Sometimes one unit can be installed over the door opening on top of the track, but very often there are obstructions and the unit would have to be installed much too high. Therefore, one unit on each side of the track would be more efficient because installation is then closer to the top of the door opening. The air curtain should be mounted three to four inches away from each side of the track to prevent interference with products being sent through.
HOW DO YOU INSTALL AIR CURTAINS ON HOT OVENS?
It is very typical to install air curtains on hot ovens like powder coating and paint booths, with inside temperature very high, it is not possible to install on top to bottom draft, and left to right or right to left will affect the product, thus in such cases they should be installed bottom to top with help of special brackets. You can contact our specialist at mitzvah on +91 92110 92110 for the same.
HOW LONG DOES IT TAKE TO INSTALL A MITZVAH AIR CURTAIN?
The average time required to install a unit is 90 ~ 120 minutes.
CAN AIR CURTAINS BE ATTACHED TO THE DOOR ?
Yes, air curtains can be coupled with the doors, with help of a plunger type and magnetic limit switches. The switches can be coupled with any kind of doors, single side, double side opening, Sliding Doors, Automatic Door, high speed shutters, Roller shutters etc..
DO AIR CURTAINS REALLY SAVE ENERGY ?
YES, mitzvah air curtains, save energy. Cooling the air is more costlier than heating it and hence when the air escapes all money spent on cooling or heating goes for a toss. The exact calculation for the same can be checked on the following link.
WHAT COULD THE CAUSE BE IF AIR LEAVING THE NOZZLE DOES NOT SEEM TO HAVE MUCH VELOCITY?
Possible causes for low air outlet velocities are:
- The suction grill are blocked or choked.
- The Blowers are mounted in the opposite direction.
- Voltage is too low.
WHY DO MITZVAH AIR CURTAINS HAVE ADJUSTABLE NOZZLE AT THE AIR OUTLET?
Adjustable nozzle, gives a desired angle to the air curtain draft, when there is a difference in internal and external conditions there is a natural exchange of air takes place. Air curtains break this pattern and the louver at the exit of air curtain can give a direction to the flow, and thus making a resultant vector with the inward or the outward draft.
WHAT HAPPENS TO THE AIR WHEN IT HITS THE GROUND?
As the air reaches the floor, in case of non re-circulating centrifugal air curtains, it will divide, sending the air inward and outward simultaneously and causing a draft both ways at the floor line. Air curtains should be properly selected, air should neither be too low, that it doesn’t reach the ground nor it should not be too high that it mixes the air from different thermal conditions. When the air hits the ground, it splits with maximum air moving towards the suction side.
WHAT HAPPENS TO THE INSIDE AND OUTSIDE AIR WHEN AIR CURTAIN STARTS?
As soon as the mitzvah air curtain starts, it creates a high velocity stream which can be termed as primary motion and there is a low pressure created on the stream along the flow and which creates a secondary motion both on the inner and outer wall of the air stream. This helps the circulation inside the vicinity, when air curtain is installed outside, thus eliminating the dead zones. Thus air wall is created between different thermal conditions.
ARE THERE ANY SITUATIONS THAT COULD CAUSE AIR CURTAINS TO OPERATE POORLY OR NOT AT ALL?
Yes. There are three applications to be avoided.
1. Negative Pressure : Air curtains will not perform satisfactorily if there is an exhaust fan in operation causing a negative pressure within the building.
- Outside Wind Velocity : The curtain of air will be strongest near the nozzle and weakest at the floor. Since air entering the building always seeks the least line of resistance, it will flow into the building a few feet from the floor at the door opening.
- Wind Tunnel Effect : A wind tunnel effect will prevent air curtains from operating properly. A wind tunnel effect occurs when there are two open doors, one on each side of the building, or a shed.
SHOULD THE CUSTOMER USE A THERMAL OVERLOAD PROTECTION SWITCH IN THE ELECTRICAL CIRCUIT?
Not necessarily. All motors used in mitzvah air curtains are equipped with an automatic thermal overload switch in the windings of the motor for protection against burnout. If for any reason the motor is overheating, the motor will automatically stop.
Possible causes for overheating are:
- Wrong voltage being fed to the motor. Too low a voltage. Phases unbalanced in three phase motors.
- Excessive vibration in fans caused by debris caught in the vanes.
- Motor dirty. Air cannot get to motor housing for proper cooling.
- Wiring hookup not properly followed, or the wire is too light a gauge from electrical panel to air curtain.
ARE VARIABLE SPEED MOTORS REQUIRED ON AIR CURTAINS?
The ability to adjust the outlet airflow is highly desirable. It significantly aids in the air curtain’s performance by allowing compensation for varying field conditions. Most of mitzvah air curtains have this feature. Please consult customer care on +91 92110 92110 for specific model offerings.
IF A WAREHOUSE FOR COMMERCIAL BUILDING IS COOLED, WHAT ARE THE ADVANTAGES OF INSTALLING AN AIR CURTAIN?
Cold Air settles down as is heavier and tends to move out of the doors as soon as they open from the bottom of the door, and hot air enters from top of the door. The air curtains stop this and makes a powerful curtain of air. The air curtain will cause the air to circulate, even inside the premises because of secondary draft eliminating the dead zones, and thus they make environment more comfortable and save on energy.
CAN AIR CURTAINS BE USED TO HOLD IN EXTREME HEAT INSIDE INDUSTRIAL CONVEYOR OVENS?
Yes, as long as the air curtain is mounted on the outside of the oven. The smaller the opening, the more effective the installation as the percent of heat loss is held to a minimum. The installation procedure in case of hot ovens is different than normal applications, thus please call customer care at +91 92110 92110 for guidance.
CAN A AIR CURTAIN BE OVER A BLAST FREEZER?
Yes. Use the same models as you would over a regular freezer. We have a special series for blast and regular freezers in which the chassis is made in stainless steel and the outer shell in aluminium and inward grills in plastic, and many other permutations and combinations. The air curtain series which we recommend for the this application with high humidity are ARS, ASS, RSS, and RSL series.
WHAT TYPE OF MAINTENANCE DOES THE MITZVAH AIR CURTAIN REQUIRE?
All motors have lifetime lubricated sealed ball bearings, making greasing or oiling unnecessary. Blowing or wiping dust off the fans and motors whenever it is visible is advisable to ensure maximum performance. Do not let the dust accumulated on the outer body, clean the same regularly.
WHAT ARE THE TYPE OF WARRANTY AVAILABLE ON THE MITZVAH AIR CURTAIN?
Most of the models of mitzvah air curtains come with a 3 year part warranty and 1 year service warranty.
HOW DIFFICULT IS INSTALLING A MITZVAH AIR CURTAIN? DO WE NEED A SPECIALIST FOR THE SAME ?
We at mitzvah air curtains, operate in different countries and continents and all the installation of all the models is on a DIY format. In case, you need any assistance, you can call us at +91 92110 92110 we will send you a process video on youtube channel. No, you do not need a specialised technician anybody can do it.
WHAT IS A MICRO SWITCH AND WHEN IS IT USED?
A micro switch activates the air curtain when a door is opened and turns it off when the door is closed. The two types of micro switches used with mitzvah air curtains are ‘plunger style’ for doors that have hinges, and ‘roller style’ for all other types (i.e. roll-up, sliding, vertical lift, track, garage style, etc.). When the door is shut, the switch’s contacts are held open. When the door is opened, the contacts are closed, thereby turning the air curtain on. Generally, a micro switch is installed when a door is intermittently in use, such as over receiving and cold storage doorways. It is preferable to allow the air curtain to operate continuously and not to install a micro switch if there is heavy in and out traffic. When using a micro switch, a motor control panel is recommended for all three-phase motors.
CAN A MICRO SWITCH BE USED ON ALL TYPES OF DOORS?
Yes. Plunger styles are used on single- or double-hinged doors that swing one way either (inward or outward). Magnetic type limit switches are used on all other types (i.e. hinged doors that swing inward and outward, sliding, roll-up, return track, vertical lift, garage style, etc.).
CAN FILTERS BE USED IN FRONT OF LOUVERS?
Yes. Filters can be used in conjunction. Generally we use a aluminum mesh filters on specific models, but we avoid using HEPA filters, because in case of excessive dust applications, they will get choked and increase the static on the fans and thus make air curtains underperform. Regular cleaning is mandatory in case of filters are used in air curtains. Even the suction area needed to suffice the volume of air is high hence make these models very bulky.
WHICH MITZVAH AIR CURTAINS CONTAIN STAINLESS STEEL BLOWER WHEELS?
The last alphabet in the model name refers to material of impeller, “S” represents stainless steel blowers. Generally Aluminium blowers are preferred because the stainless steel blowers are very heavy as compared to Aluminum and the plastic blowers, thus in case of stainless steel blower we need heavier motors to generate the same CFM, hence consuming more energy.
IS MITZVAH A MANUFACTURER ?
YES, mitzvah is a manufacturing company, with a proud participant of make in india campaign and the manufacturing unit and the processes are ISO 9001:2015 certified. mitzvah is a MSME Company and is also registered with NSIC. The products also also CE certified.
DOES MITZVAH SUPPLY AIR CURTAINS IN SAUDI ARABIA ?
Yes, we supply in saudi arabia and have SASO certifications for the supplies that go to saudi and have all the facilities to manufacture and test air curtains on 220V, 60Hz.