Principle of operation and selection of a heat curtain

To warm up a room that has one or more doors constantly open can be quite a challenging task. Even when heating devices are working at maximum capacity, the heat is still able to escape through the doorways.

An effective solution to this problem is to install a barrier in the doorway that allows people to pass through, but prevents external air flow. This barrier is commonly known as a heat curtain, as it creates a continuous stream of warm air in the open doorway, effectively trapping the warm air inside and preventing cold air from entering.

The doorway is safeguarded by the airflow.

The principle of operation of any heat curtain

The purpose of this protective device is to utilize the air to create a barrier against outside elements. Specifically, it generates a stream of insulated air that encompasses the entire doorway. This curtain not only retains the room’s warmth, but also blocks the intrusion of dust, foreign odors, and even insects from the exterior.

Heat curtain devices effectively retain heat in places where doors are frequently open, such as stores and garages. In large country houses, there may also be situations where the doors are consistently open.

Naturally, purchasing a heat curtain requires investment, and its operation requires energy consumption. However, the heat retention effect provided by the curtain enables heating systems to operate at lower power levels, resulting in overall cost savings. Additionally, modern heat curtain devices are equipped with automation, which activates the air barrier only when the door is open. When the door is closed, the curtain is deactivated and does not consume energy.

The device of a heat curtain

The concept of the device, which simplifies its operation by creating an air barrier, can be described as a fusion of heating components and a fan. The fan propels the warmed air, while the outlet channels and shutters produce a broad and even flow, aimed at the designated area.

Streamlined design of a heat curtain

Naturally, the process is not quite as straightforward. Standard axial fans do not suffice for generating a broad and consistent air current. Radial and diametral fans are utilized to generate a high-quality air barrier. It takes the form of an elongated cylinder with blades spanning the entire length.

Operating principle of a heat curtain

Typically, a heat curtain is powered by an electric motor positioned on the side. However, there are also designs where the motor is centrally located and drives two turbines on either side. This particular configuration necessitates a complex duct arrangement to avoid the formation of a narrow section in the middle where the air shield would not be produced.

Air shield devices differ in terms of their installation location, heating element type, and control methods.

Place of installation

The air curtain can direct the heat flow either vertically from top to bottom or horizontally from the sides of the protected opening. It would make logical sense for the device that directs the air vertically to be called vertical. However, due to unclear tradition, these curtains are referred to as horizontal. On the other hand, curtains that drive the air across the doorway are called vertical curtains.

There are different variants of curtains based on their installation location:

• Horizontal curtains are placed above the opening that needs to be "closed". The airflow is directed from top to bottom. This type of curtain is the most common because it is the easiest to install.

Horizontal heat curtain

• Vertical heat curtains are installed on the floor and placed on the sides of doorways. This configuration makes the device more difficult to manufacture and install. Why would you need a vertical air curtain? It is necessary when there is limited space above the door for a horizontal unit. Additionally, for narrower doors, a vertical air curtain may be more effective.
• There is also a rare type of heat curtain known as recessed curtains. These devices are designed to be hidden behind a suspended ceiling. The airflow is directed through a decorative grille.

Types of heating elements

In order to guarantee a dependable defense for the room during chilly conditions, it is imperative to heat up the air beforehand prior to venturing outside. This objective is accomplished through the use of air blowers and heaters. There are three distinct types of heating elements that are utilized in heat curtains:

Electric

The most prevalent form of heating elements are tubular electric heaters, known as TENs, which generate heat through a nichrome spiral housed within an insulating tube. These heaters are known for their reliability and ease of operation.

Recently, the use of STICH elements has grown in popularity for electric heat curtains. These elements also utilize a nichrome wire or tape to generate heat when an electric current passes through them. The wire in these elements is arranged in a needle-like pattern, similar to radiators.

Thanks to this unique design, STICH elements heat up instantly, resulting in a high air temperature at the outlet. However, they have the drawback of burning any dust that falls on them, causing a burning odor. Additionally, all electric heaters are associated with the relatively high cost of electricity.

Water

These devices, known as water heaters, function by releasing heat from the warm water flowing through them. The installation and operation of these units can be quite challenging.

A heat curtain requires a water heater of specific type.

Gas

One of the most cost-effective options might be the models that run on liquefied gas. However, it’s important to note that there may be a potential risk of accidents associated with any type of gas equipment.

Control methods

To manage and regulate the functioning of thermal protection devices, there are both manual and automated options available. The primary techniques for control include:

• Switching the device on and off. Automating this process in sync with door opening results in cost and resource savings for the air curtain. The protective airflow is activated only when the doors are open.
• Monitoring and controlling the airflow temperature. In simpler devices, this is done through a manual temperature switch. However, in more advanced devices, the degree of heating is adjusted based on the temperature of the outside air. For example, during hot weather, the heating elements can be turned off, while the curtain still ensures a cool indoor environment.
• Remote management of operating modes is achieved through a portable remote control.

Technical characteristics

In order to select an appropriate heat curtain, it is important to understand the key technical parameters of these devices. You should select a device that will effectively protect your door by considering the following:

• Dimensions: The length of the device should be sufficient to cover the entire width of the doorway. Even a small gap can significantly reduce the effectiveness of the protection against external influences. For wide doors in large spaces such as supermarkets or car repair shops, multiple devices can be installed along the width of the opening. The height of the device is also important. If it exceeds the available space above the opening, it may be necessary to consider only vertical curtain options that can be located on the side of the door.

Designing a lengthy heat barrier consisting of four components

• Air current performance. The objective of the heat barrier is not to heat the room – this task is carried out by other devices. Therefore, the power of the fan and, consequently, the volume of airflow per unit of time and its velocity are the key metrics of the heat barrier. To ensure a reliable protective airflow, its speed at the far end should be approximately 2 m/s. In order to provide such airflow velocity at ground level, it is necessary for the device to generate a velocity of about 8 m/s when positioned at a height of 2.5 m. Achieving these velocities requires units with a capacity exceeding 600 m3/hour.
• Noise level. Although this is not the most decisive factor for industrial buildings and large supermarkets, it is crucial for household appliances. In a home setting, a noise level below 70 dB is desired for comfort.
• The presence of automated control is crucial. Manual mode is only suitable for basic and low-cost options. Automatic control of the curtain’s operation and the temperature of its heating elements ensures efficiency and cost-effectiveness.
• Protective mechanisms are essential. To ensure safety, it is necessary to have the capability for automatic system shutdown in case of overheating.

Popular models of heat curtains

Take into consideration the top-rated options:

• The Tropic M-9 model is regarded as one of the most basic yet efficient horizontal thermal protectors. It is primarily designed for industrial premises, as it operates on a 380V network and its design is not flashy. It has two power levels – 9 kW and 4.5 kW. Its productivity is impressive, with a capacity of over 1100 m3/hour. The installation height should not exceed 2.3 m. The price ranges from 12 to 13 thousand rubles.

Discover the Tropik M-9 powerful curtain:

• If you are looking for a suitable model for domestic use in homes and apartments, the Ballu BHC-L06-S03 could be a great option. This model may not have high power, but it offers a quiet and affordable solution. The Ballu BHC-L06-S03 operates on 220 V and features two switchable power levels: 3 kW and 1.5 kW. The heating is powered by STICH elements. Additionally, it can also be used without heating. With a capacity of 350 m3 per hour, this model effectively circulates air. The noise level is only 46 dB, ensuring a peaceful environment. Priced at 5 – 6 thousand rubles, it offers great value for money. The only downside is the absence of a remote control.

Ballu BHC-L06-S03 is a heat curtain designed for household use.

• Teplomash, a domestic manufacturer, offers an entire range of thermal protection devices. One notable household model is the KEV-3P1153E. It has a decent capacity of 500 m3 / hr, while also being low-noise at 45 dB. It features two-stage power regulation with options of 3 and 1.5 kW. The maximum installation height is 2.2 meters, and it is priced at around 6,000 to 7,000 rubles.

Teplomash KEV-3P1153E is an exceptional thermal curtain.