10 most common mistakes when choosing a thermal curtain

In an era when energy is one of the most important issues, air curtains become an invaluable tool for its preservation. This energy-saving equipment, which prevents the penetration of cold air into the premises through door or window openings, has been in steady demand for many years. The reason for this popularity is the effective and convenient operation of such equipment, for which there is simply no alternative.

Consider the main advantages and disadvantages of thermal curtains, as well as the most common mistakes when buying and connecting.

Error 1: Buying a thermal curtain of insufficient capacity (“pumping”) can be a waste of money and time: a stream of cold air will penetrate the room through the bottom of the opening. As a result, the inside will still be cold or the temperature will be unstable (heat losses can reach 70%).

An important point is the understanding that the protective properties of thermal curtains are determined by the speed of the air flow (depending on performance), and not temperature (which depends on power). At the same time, the speed to the bottom of the opening gradually decreases (at the floor it can be 2-3 times less than at the very exit from the apparatus).

It is for this reason that low-power models should not be chosen: even with their wide enough width, there will still be a gap for cold penetration from below. To make an exception (select performance less than 300m3 / hour) is possible only for rooms with a vestibule (double doors) that form an additional barrier.

To achieve the greatest efficiency and reduce energy consumption, you can listen to the following recommendations of the ratio of the height of the opening and performance:

• up to 1.5 m - 300-400 m3 / hour,
• up to 2.0 m - 500-650 m3 / hour,
• up to 2.5 m - 700–950 m3 / hour,
• from 3.5 - from 1200 m3 / h.

In especially windy areas, a certain amount of productivity should be made in order for the air flow to hold the wind gusts (on average, the outer doors should move at a speed of 8 m / s, at technological openings and gates with 25 m / s). In this case, experts recommend to prefer the model with heated air.

Error 2: Incorrectly chosen length of the heat curtain may cause the air flow to be too narrow (cold can penetrate from the left and right sides of the opening).

Ideally, to create a reliable barrier, the length of the heat curtain should be equal to or slightly wider than the opening, but it is allowed to be 5% shorter, since the air flow is wedge-shaped.

Curtains produced today can be 0.8-2 meters in length. If you want to block the flow of cold air in the openings of more than 2 meters, then several devices are installed in a row, with the ends to each other (at a distance of no more than 50 mm). In this case, you should pay attention to the design of the blocks (ease of docking).

Error 3: Inattention when choosing a design can result in the formation of air "dips", significantly reducing the protective properties of the air flow and creating uneven blowing of the heating elements (which leads to their breakage).

It is worth refusing constructions with several turbines. The fact is that the turbine is the most important element of the thermal curtain, which actually creates the air flow. The most optimal conditions are created by thermal curtains with a turbine located along the entire length (and the engine that drives it is located on the side). However, some manufacturers, trying to reduce costs, simplify the design by installing two large turbines at the edges instead of one large one.In this case, the engine is located in the center of the curtain, and this is precisely the reason for the formation of a “failure” in the air flow and uneven heating.

Error 4: Incorrect choice of the installation location of the heat curtain (not where it is needed, but where it is possible) reduces the efficiency of work and leads to rapid wear of the fan bearings, and as a result, to breakage.

It should be noted that the installation side does not really matter: air curtains, installed on both the warm and cold sides, work equally effectively.

There are horizontal curtains (installed on top of openings), vertical curtains (on the left or on the right side) and devices that create a stream of air directed upwards (used to protect large 5-8-meter openings and installed in a special glow on the floor).

Experts recommend choosing vertical side models when the opening width is significantly greater than its height. Such curtains can reduce the cost of equipment (the purchase of one high-performance vertical curtain will be cheaper than a few less productive horizontal devices). Moreover, the requirements for the length of vertical curtains are somewhat different: their length can be 75-80% of the height of the opening.

It is impossible to install the curtains in the position for which they are intended, this leads to rapid wear of the fan bearings. If it is not possible to fix the curtain directly on the wall, beam or ceiling, special frames are used. For stability of work, the direction of the air flow should also be adjusted (a slope of 5-10 ° to the street is allowed). In modern models, the function of changing directions is performed by built-in blinds.

Error 5: The inconsistency of the wire cross-section during the installation of the heat curtain may cause work in an uncharacteristic electric mode, as well as lead to excessive heating, which is dangerous for the insulation and contact connections (fire and explosion may occur).

The mismatch of the wire section with the power of the heat curtain is the most common mistake. It should be borne in mind that such equipment works non-stop for a long time, which means that it is necessary to choose a wire with a larger section (by 30-50%) than is recommended for the selected power.

It should be remembered and grounding, providing current drain during short circuits and in other situations.

Error 6: Incorrect attachment of heat curtains can lead to vibrations, noise, and as a result to breakdowns.

Of course, the best option for installation will be the use of special fasteners. However, they can be chosen individually. The main thing to consider is the weight of the curtain and the surface material. As a rule, thermal curtains, both for horizontal and vertical installation, are hung by holes in the rear wall of the casing. In this case, the hanging can be made on fasteners or brackets mounted directly into the wall. They are attached to the ceiling or to the supporting structure of the air curtain using threaded rods, hollow cylindrical rods or using the brackets supplied.

The material of the surface to which the curtain is attached should also be taken into account. For example, when installing heat curtains on bearing plates, you may need to use a dowel with a flange and an elongated non-expansion part.

The resulting noise and vibration can be eliminated by strengthening the mountings.

Error 7: Not observing horizontal position during installation creates an uneven load on the bearings, and they can fail.

When installing any type of heat curtains, the system axis should be placed in a strictly horizontal position. The displacement of the axis leads to incorrect (uneven) distribution of the load on the bearings, which leads to their breakage.

So that air can circulate freely, it is necessary to make gaps above and from the sides of the veil.

Error 8: Installing a temperature sensor directly under the curtain will cause it to be permanently turned off.

If you install a temperature sensor directly under the heat curtain, then due to a small temperature difference it will constantly turn off. Ideally, temperature sensors are installed inside and outside the room. At the same time, thermostats are recommended to be installed in the door area, preferably in places where they will record the temperature change with the greatest accuracy.

Error 9: Lack of regulation and control can be the cause of inefficient and uneconomical operation of the thermal curtain.

This is especially true for large openings. The simplest automatic devices (for example, gate / door opening sensors, temperature sensors, speed switches) and control units significantly reduce the operating costs of air curtains (for example, one fan works instead of two, or the curtain turns on only when the gate opens, and the wind speed increases the flow , changing the position of the blinds, etc.). The most convenient with this remote or remote control.

Speaking of savings, you should stop on the choice of the method of heating (it can be electric or water). If the infrastructure allows, it is better to stop the choice on a water heat curtain, for which you have to make a withdrawal from the central heating system, to work more efficiently, connect a pump, and also install a filter to prevent blockages in the heating elements.

An important point is the pollution of the filters. This greatly reduces the efficiency of the air curtain. Status indication or built-in timer warning that the time has come to clean the filter will not be superfluous.

It is worth noting that the relatively high cost of heat curtains with different control systems and more complex controls pays off in a short time.

Error 10: Incorrect operation (in particular, incorrectly selected temperature conditions) can cause breakdowns of construction details (switches, electronic boards, fan, turbines, grids and other parts).

The general guidelines for temperature selection are: 50 ° C for exterior doors, 70 ° C for exterior openings and gates. Thermal overload of the system leads to the melting of switches and grids, the burning of electronic circuit boards and turbines, the fan stops. Follow the manufacturer’s instructions for use.

It is also important to carry out maintenance (M) thermal curtains. The frequency will depend on the environment in which they operate. The more dusty the air, the more attention will be required. Most manufacturers recommend maintenance (external inspection, checking the integrity of the unit, mounting strength, control panel operation, power supply diagnostics, cleaning air filters, housing and louvers, lubricating the bearing group) at least once every 4 months.

With proper operation, thermal curtains fail quite rarely. But completely, of course, this possibility is not excluded. Therefore, choosing a manufacturer, it is worth considering that if a Russian model breaks down, it will be possible to repair it much faster and easier (it will be easy to purchase parts), while for foreign analogues you will have to order them, and this will take longer (and they cost more ).