How to choose a heat gun. Comparative analysis
The heat gun is one of the fast and powerful types of room heating. To select the desired design of the heat gun, we will conduct a brief analysis.
Content
- What is a heat gun
- How to correctly calculate the necessary heat output of a gun
- Electric heat guns video
- Gas heat guns video
- Diesel heat guns video
What is a heat gun
In our climatic conditions, even with enhanced warming of the premises, using modern finishing heaters, using heat-insulating plaster - you can not do without heating.
The heat gun, like conventional heaters, consists of a heating element, a housing and a fan. Since such a technique can establish a comfortable temperature in the rooms in a matter of minutes, a very powerful fan is used in the heat guns.
The fan forces air to pass through the heating element, thereby creating a powerful heat flow.
Heat guns are mobile, which allows you to move them from one place to another.
Externally, this unit resembles a gun, has a cylindrical body, is located horizontally or at a slight angle up.
Very often, it can be said mainly, heat guns are used at a construction site or industrial facility.
How to correctly calculate the necessary heat output of a gun
Before purchasing this unit, you need to know the size and volume of the room in which the heat gun will operate, whether people will be there permanently.
It is necessary to decide what type of fuel the consumer will use - electricity, gas or diesel.
Any good seller, before offering a model, will ask leading questions.
For example: the volume of the room, depending on this volume, the necessary gun performance is selected. With an average ceiling height of 3 meters, one kilowatt of heat generated is enough to heat about 8 to 12 cubic meters. The larger the room, the more powerful the equipment should be.
There are formulas by which you can independently calculate the required thermal power.
Thermal power (kcal / h) is equal to Vx ^ TxK. V is the volume of the heated room, i.e. product of width by length and height (cubic meters);
^ T is the temperature difference between the outdoor air and the required indoor temperature, in degrees Celsius;
K is the dispersion coefficient, depending on the type of construction and insulation of the room.
A simplified wooden structure or a corrugated sheet metal structure without thermal insulation has a coefficient of 3 to 4;
a simplified construction of a building from a single brickwork with a simplified construction of windows and a roof, with a small thermal insulation has a coefficient from 2 to 2.9;
standard design with double brickwork, with a small number of windows, standard roof, medium thermal insulation, has a coefficient from 1 to 1.9;
improved design, brick walls with double thermal insulation, a limited number of double-glazed windows, a thick floor base, a roof made of high-quality thermal insulation material, high thermal insulation - coefficient from 0.6 to 0.9.
One kilowatt is 860 kilocalories per hour.
But any theoretical calculations do not always give an accurate result, since much depends on the circumstances.
For example, if the building has very high ceilings, the use of infrared heaters is recommended, they do not heat the air, but the surface of objects from which heat is transferred to the air.
To correctly choose a heat gun, you need to know how to heat the air flow with this technique.
The guns are divided into several types: electric, diesel and gas guns.
Each type has its own characteristics and advantages.
Electric heat guns
If it is possible to connect to electricity, you can install electric heat guns.
The so-called fan heaters are popular today in everyday life and construction.
Such guns are mobile, convenient in operation, do not require additional fuel, operate from the network.
Models up to 5 kW. They are powered by 220 volts, more powerful from 380 volts.
Heat is generated when current flows through a conductor with high resistance, the fan blows heat from the heating element and brings it to its destination.
Currently, on most heat guns, TENs are used - heaters, in which the wire is placed inside the tube, the tube itself is made of austenitic or non-austenitic steel.
Tubes made of non-austenitic steel become less heated, more durable, but carry less heat load per unit area. For stronger heating, it is necessary to use longer heating elements.
Tubes made of austenitic steel are oxidized during operation, microcracks appear, this can lead to the risk of explosion of heating elements.
Electric guns are relatively small in size, take up little space, but their productivity is not very large, they are not suitable for heating rooms with high humidity (baths, saunas, etc.).
Electric guns consume a lot of electricity, so such models are used in short-term operation.
Gas heat guns
Such models weigh a little and are inexpensive.
Power usually ranges from 10 to 100 kW., But there are more powerful ones.
The only problem is fuel, liquefied gas in cylinders is not sold everywhere, it is difficult to make a fuel supply, as a number of requirements apply to the storage of gas in cylinders.
Gas guns are economical, when burning gas practically does not emit harmful substances, but ventilation is still necessary.
The consumer should know that the gas pressure in the line or in the cylinder must correspond to the selected heater model.
For the simplest model with a power of 10 kW., A pressure of 0.5 bar is needed. The more powerful the gun, the greater the pressure.
For safety reasons, many guns have flame control and overheat protection.
Gas guns are sensitive to low temperature, in severe frosts they can work unstably.
Diesel heat guns
Diesel guns are similar in principle to gas guns and use diesel fuel as fuel.
It has a number of disadvantages, namely: a rather high weight, since the gun has to be transported along with the tank.
The design of diesel guns is more complicated.
Fuel is supplied to the combustion chamber by a fuel pump or compressor - all this leads to a rise in price, and additional units require additional maintenance.
Compared to gas, diesel fuel is more contaminated with impurities; therefore, such guns can be turned on in non-residential premises with ventilation.
But the merits of these guns are decent.
Fuel is available, its consumption is very economical, one refueling is enough for continuous operation for 10-15 hours.
The transportation of diesel fuel is safe, the heating system is not tied to the gas line, the power is the same as that of gas guns.
The diesel gun can operate in a wide thermal range.
Some models relate to devices of indirect heating; for this, guns use an additional circuit - a heat exchanger.
Hot gases pass through the heat exchanger and go outside through the chimney, the heat is removed using a fan.
The efficiency of such guns is less, the price is higher, but there is no need to worry about ventilation and ventilation.
Such models are designed for heating large volumes in workrooms.
It must be understood that for the operation of diesel and gas heat guns, a small amount of electricity is still needed to power the fan and the automation system, but if necessary, the gun can be powered from a small generator.
