Thermal International Co.,Ltd

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1. Analyses & Solutions to the Matter of Electric Heating Element

Q1: What is the heating zone of the electric heating length?

A: Generally speaking, there’s a 6~8cm heating zone on the electric heating length. It is recommended that the oil level had better to be above 8cm, so as to avoid the deoiling and dry burning while heating. (if the oil level is less than the maximum 8cm heating zone length, then it will cause the deoiling & dry burning, and the upper part that is above the 8cm-line will turn red. If that case, users need to cut off the power supply immediately and refuel the heating equipment, so as to prevent the heating element from being decrepitated and broken.)

Q2. The power of the heating element is less than 2500W?

A: We guarantee that the power of our electric heating element is within 2300W~2500W, with a 5% power tolerance. There won’t be the question or doubt of insufficient power. (According to the previous feedback from our customers, we notice the matter of insufficient power, and we immediately discuss with the factory and notify them to pay much attention to it during the future orders. Besides, we generally will carry out the power detection before delivery, so as to ensure the full power and quick heating capability. Quality is guaranteed.)

Q3. About the life time of our electric heating element?

A: Actually, under normal use, i.e. no deoiling or dry burning, the life time is electric heating element is acceptable. But that depends on different customers’ specification application & use. What’s more, it is also has something to do with the cleaning frequency. What’s the reason why different customers will have different opinions towards the quality of our electric heating element. (It is generally recommended that the electric heating element should be replaced every half a year, since the use of the electric heating element will lead to the aging of the electric stove wire, which to a certain degree, will increase the heating time and the power consumption.) 

Q4: What’s the difference between the 304 heating element and the ordinary heating element?

A: They’re mainly different in material. The 304 heating element applies the high quality Stainless Steel 304, while the ordinary heating element uses the Stainless Steel 201. Besides, as for the screw part, the former uses the stainless steel screw, while the latter is made of iron.

       Based on our customers’ feedback, here we list the relevant analyses and solutions to some of the most concerned questions. Besides, we always will carry out the leakage current-detecting and quality control. Therefore, our quality is surely guaranteed! Please feel free to contact and purchase! 

2. The Most Effective Method to Verify the Quality of Electric Heating Element.

First, wipe the electric heating element surface carefully, and then turn on the AC 220V power supply, observe its burning in the dry air. Cut off the power once the surface is turning red. After the electric heating element cooling completely, wipe the surface with a clean paper napkin. If there’s no black oxide powder(no chemical reaction with oxygen in the air), then it is the electric heating element of good quality. Otherwise, there’s the black oxide powder that reflected the chemical reaction with the oxygen in the air, then it’s not of good quality, it’s impure.

The correct formula is: C *M*T=P (power) *T (time).

C=the specific heat capacity of heating matter;

M=the total mass of heating matter

T=the temperature difference

P=the power

the 2nd T=time

3. Main function of the thermostat.

  • Convenient ---- Automatically timing everyday, adjust the wall-hanging stove in advance or delay. Users don’t need to set it everyday. And that’s the best choice and the most necessary to the office workers.

  • Comfortable ---- Automatically raise or low the indoor temperature during various period of the day. It will smartly protect the users from the cold when they wake up in the morning or back to home in the evening.

  • Energy-saving ---- More advanced and intelligent control of the indoor temperature, and changes with the different period of the day, users do not need to burning the gas for heating day and night.

  • Reliable ---- When the indoor temperature is too low, it will start the wall-hanging stove automatically. And it will need pretty less gas for the safer indoor cold prevention. 

4. Difference between the Cartridge Heater & the ordinary Heater

1). appearance: there’ s only one outgoing line(one end) of the cartridge heater, while the ordinary electric heating element has two outgoing line(two ends); 


Cartridge Heater-1 (with 1 end)


Cartridge Heater-2 (with 1 end)


Ordinary Electric Heating ELement-1 (with 2 ends)


Ordinary Electric Heating ELement-2 (with 2 ends)

2). the internal structure: they are different in the way of wire running. Especially the current imported cartridge heater, it is quite different from the ordinary electric heating element;

3). production process: there are more complex techniques being involved during the manufacturing of the cartridge heater. For example, the contracted pipe, it ensures the higher power and longer life time of the cartridge heater. 

4.Matters Need Attention During the Use of the Electric Heating Element

1. The electric heating element shall be allowed to work under the following conditions:

1). the relative air humidity is no more than 95 %, no explosive and corrosive gas;

2). the working voltage shall be no more than 1.1 times of the rated value, and the enclosure shall be                  effectively grounded;

3). the insulation resistance ≥ 1m Ω; dielectric strength: 2 KV/ 1 min.

2. The electric heating tube shall be well fixed, and the effective heating zone must be fully immersed in liquid or metal solid, and burning out is strictly prohibited. When the surface of the heating element body is found to have water stains or carbon formation, it shall be cleaned in time before using, so as to avoid the influence of heat dissipation and even further shorten the service life.

3. When heating the fusible metal or solid nitrate, alkali, leaching, paraffin, etc., users need to low the using voltage. After the medium is melted, then restored to the rated voltage.
4. When heating the air, the elements shall be arranged in a uniform manner so that the elements can have good heat dissipation conditions, the air flowing through can be fully heated.

5. When heating the nitrate, safety measures should be considered in order to prevent explosion accidents. 

6. The connection part shall be put outside the insulating layer so as to avoid the contact with corrosive, explosive medium and water; the lead wiring should be able to withstand the temperature and heating load of the connection part for a long time, and the wiring screw should avoid excessive force when tightening. 
7. The electric heating element shall be stored in the dry place: once the insulation resistance is lower than 1MΩ due to the long-term shelving, it can be restored if dried in the oven at about 200 ℃ or heated with low voltage power supply.
8. The magnesium oxide powder of the outlet end of the electric heating element shall be prevent from the penetration of contaminants and moisture, so as to avoid the occurrence of the leakage accident.

5. How to Select the Most suitable Electric Heating Element?

The electric heater, generally is a kind of metal tubular heating element, it is to put the thermal element into the metal tubular pipes. And to fill the gap part with crystalline magnesia powder which is of good heat resistance, thermal conductivity and insulation. It is most common in many thermal equipment. How to select the most suitable electric heating element? It’s not only a knowledge but also a liability requirement for technology and products. Therefore, choice whrn purchasing is of great significance.

Methods & Steps:

The Power value needs to be taken into consideration when there’s the selection of a suitable electric heating element. The element’s power can be easily achieved according to the standardized and uniform calculations, three steps are listed as below:

1. calculate the actual power that is required to maintain the temperature, under the constant medium temperature.

2. calculate the required power that heating from the initial temperature to the set temperature within the specified time.

3. based on the above two results, choosing the right electric heating element type as well as quantity. The total power is the maximum of two types of power value.

1. the required power to maintain the temperature of the medium:
KW= C2 △ T/864+P
In the formula: M3 refers to the increase of medium (kg/h) per hour.
2. the power required for initial heating:
KW= ( C1M1△T+C2M2△T))÷ 864/P+P/2

C1C2 respectively refer to the specific heat capacity of the container and the medium(Kcal/Kg℃);

M1M2 respectively refer to the weight of the container and the medium(KG);

△T refers to the difference between the required temperature and the initial temperature(℃);

H refers to the required time that heats from the initial temperature to the setting temperature(h);

P is the thermal discharge of the container at the final temperature(KW). 

6. Working Principle - How the thermostat works?

      When the electric heating product works, the inside temperature sensor usually will be set to automatically sampling and real-time monitoring the ambient temperature. Once the ambient temperature is higher than the control set-point, the control circuit starts, it can set the black-lash. And if the temperature is still rising, when it rising to the overlimit alarm temperature point, then start the initiate overlimit alarm function. When everything is tried, and the temperature rising is still out of control, it can use the tripping function to stop the running of the equipment, then so as to prevent it from being further damaged. 

       It is mainly used in the field of temperature controlling, such as the oven, stove, gas, microwave, refrigerator and so forth.

7. Empty Thermal Explosion Matters Analysis of the Electric Heating Element

      The electric heating element is a kind of safe and efficient electrothermal product. It can heat objects of all kinds, what’s more, for some special type, it can also heat the air. Of course, it only will be succeeded under certain circumstances. 

       Thus, if there’s the matter of electric heating element’s empty thermal explosion, it might due to the following factors:

1.There’s something wrong with the 304 Stainless Steel pipes;

2.There’s something wrong with the magnesium oxide;

3.Leakage problem of the electric heating element;

4.Matter of the heating element’s design: the power of per unit meter is too high than the normal. Normally, the unit power/meter of the dry electric heating element is 1KW, and if added with big diameter or fins, together with the well control of fan cycle and temperature, it can reach 1.5KW per meter. 

5.Constant work of the electric heating element, no control towards the temperature & the fan cycle.

There’ re many models for the electric heating element. And can be used in different working environment. The research and development work of each type is exclusive, i.e. can not be applicable to all kinds of environments. Therefore, it is pretty significant for the user to have a good understanding of the products’ properties before choosing. That will to a certain degree avoid many unnecessary trouble. 

8. Function and installation considerations of thermal protector (temperature switch)

Functional characteristics:

Thermal protector is a kind of component that provides very reliable protection under the condition of over temperature, it has small volume, large flow, no reset, stable performance, easy installation, and has a certain range of humidity settings and bearing capacity to meet the customer's application needs. 

Application domain: 

It is widely used in household electrical appliances, industrial equipment and health products, acting as a kind of after-thermal protection. Once there is the temperature control failure and other overheating, the heat fuse will cut the circuit to protect the it from harmful overheating damage.


Installation notice: 

1). when the lead is bending used, it shall be bent above 6 mm from the root ; when bending, pls do not damage the root and lead, without force pulling, pressing and twisting. 

2). once the thermal protector is fixed with screws, riveting or terminal, it shall be able to prevent the occurrence of the mechanical creep and the occurrence of the undesirable contact phenomenon. 

3). the connecting parts shall be able to work reliably within the scope of work of the electrical products, and shall not be displaced by vibration or shock. 

4). when there is the lead welding operation, the heating humidity shall be limited to the minimum, and attention pls, it shall not be given to the high temperature on the fuse. Do not forcibly pull, press, twist the thermal protecto and lead. After welding, it shall be immediately cooled for more than 30 seconds. 

5). the thermal protecto can only be used at the specified rated voltage, current and specified temperature, pls paying particular attention to the maximum continuous temperature of the fuse. 

Note: the maximum continuous temperature current, the length and temperature of the lead wire can be designed according to the customer's requirements.

9. Selection of the sealing material for W-type finned heating element

    The effect of the sealing material is to prevent moisture from the air from entering the magnesium oxide powder, in case the magnesium oxide powder is damp, the insulation performance will be reduced, then generate the electricity leakage of the electric heating element, and even become invalid. The modified magnesium oxide powder can be unsealed. The main material used for sealing ( moisture - proof ) of electric heating element is glass, epoxy resin, silicone oil, etc.