Heating Preheating RodDarui Electric recommends for you
First generation bimetallic strip mechanical temperature control, second generation thermistor detection control temperature, third generation intelligent heating rod.
First generation heating rod directly uses bimetallic strip mechanical temperature control, which is the most common. Simply put, a bimetallic strip is placed inside the heating rod. The bimetallic strip is made of two different materials bonded together using special technology. When temperature changes, due to different expansion coefficients, the metal strip deforms according to temperature changes. The bimetallic strip is placed inside the heating rod as a contact switch. Using this, it can automatically disconnect the contact to control temperature when the temperature is reached. It has the disadvantage of
inaccurate temperature control. The internal bimetallic strip and its temperature control contacts are the core of the constant temperature heating rod. Inferior bimetallic strips are prone to fatigue during use, causing the bimetallic strip to fail to open or close the heating rod with temperature changes. Additionally, inferior contact switches are prone to arcing and sticking, causing large temperature fluctuations. The advantage is that the price is relatively cheap.
The external contact materials are divided into three types: 304 stainless steel heating rod, glass tube heating rod, and quartz heating rod. Later, another type of heating rod with a controller and digital display was upgraded on the market. The materials are also the above three, with an added digital display control box, making temperature control more convenient and safe.
Second generation thermistor detection temperature heating rod, which uses a thermistor to detect temperature, amplifies the signal, and uses a thyristor to control on/off. We often call it an external temperature control heating rod or split temperature control heating rod. Its working principle is that the temperature control system outside the tank controls the water temperature inside the tank through a thermistor probe in the tank water, heating while the temperature control system and heating system are separated.
Advantages are faster heating and more accurate temperature control. The thermistor and heating rod can be placed far apart, which overcomes the disadvantage of bimetallic strip temperature control. However, other
disadvantages are also obvious. First, there is an extra thermistor wire, making installation more complicated. Second, if the thermistor accidentally leaves the water surface, it will keep heating, causing the tragedy of "boiled fish". But now, to address this disadvantage, brands like Sunsun and Chuangxing heating rods have added a thermistor out-of-water power-off alarm function, and many temperature controllers use LCD display temperature for control.
Third generation heating rod is an
intelligent heating rod controlled via APP. For example, JiYin uses WiFi to remotely control the heating rod via a mobile phone APP, and can set the desired safe temperature range. It is the latest heating rod technology. Through the interaction of monitoring unit, control unit, and regulation unit, the ecosystem transitions from an unstable state to a stable state. Compared with traditional heating rods, traditional heating rods only have a regulation unit, cannot accurately identify temperature, and work mechanically. This is the difference of intelligence.
II. By material:Glass heating rod: Generally uses an explosion-proof glass shell, with the characteristics of low price, wide application range, and can be used in various aquariums. The disadvantage is that it is easy to break. If used in large fish tanks, a protective cover must be equipped to prevent damage by fish.
Stainless steel heating rod: Generally uses a stainless steel shell, with advantages such as sturdiness, durability, and texture. However, the disadvantage is that it cannot be used in certain corrosive environments, such as saltwater tanks.
Quartz heating rod: Uses specially processed milky white quartz tube, equipped with resistance composite materials, durable, corrosion-resistant, and can be used in saltwater tanks. However, the disadvantage is that the price is relatively high.
Ceramic heating rod: PTC ceramic heating rod is a commonly used ceramic heating rod, composed of PTC ceramic heating element and aluminum tube. It has the advantages of low thermal resistance and high heat exchange efficiency, and is an automatic constant temperature, energy-saving electric heater. Another MCH ceramic heating rod uses alumina ceramic, which is a new type of high-efficiency, environmentally friendly, and energy-saving ceramic heating element with built-in electric heating wire. Compared with PTC ceramic heating elements, MCH material is more environmentally friendly, saves 20-30% electricity under the same heating effect, and has a longer service life.
Usage precautions:
① Do not power on the heating rod in the air. Because it heats up extremely fast in the air, it may burn out the heating rod at best, or shatter the glass or burn hands at worst. Even after power off, do not immediately take it out of the water, as the temperature is still very high, which can easily burn people and damage the heating rod.
② It is recommended to replace the bimetallic strip heating rod every one to two years, because the internal bimetallic strip may malfunction after long use, to avoid unnecessary losses. The replaced heating rod can be used as a backup or for heating during water changes.
③ Repairing a heating rod is not cost-effective. Ordinary bimetallic strip heating rods are relatively inexpensive, and safety cannot be guaranteed after repair. Split heating rods are beyond the ability of ordinary people to repair, and the cost of hiring a professional for repair is not much less than buying a new heating rod.
④ When changing water, be careful not to let the water level drop too low, exposing the heating rod.
⑤ Frequently observe the heating rod and thermometer. Do not rely on the indicator light of the heating rod; the water temperature should be the standard.
Usage experience:
1. Heating rods have a service life, generally not exceeding two winters. Over time, the wires age, contacts oxidize, and may malfunction. Even imported heating rods claim a lifespan of 1-2 years in the manual. To be safe, you can use the heating rod in combination with a temperature controller. There are many brands of domestic temperature controllers, and the price is not high. Set the heating rod temperature slightly 2°C higher than the temperature controller, so double insurance can avoid the tragedy of boiling fish soup.
2. Power selection of heating rod: Generally calculated based on the volume of the tank. Each liter of water should have 2W of heating power. If a tank has 300 liters of water, the total power of the heating rod should be at least 600W. Heating in winter may be the most power-consuming expense. I strongly recommend that everyone take insulation measures for their tank. Buy a few 2 cm thick foam boards, stick them on the back and sides of the tank, and make a well-sealed lid for the fish tank, which can greatly reduce energy loss. This only takes a little time and a small amount of money, but can save a lot of electricity bills. Why not? Remember, every penny we pay is our own labor reward, why go against our wallet?
3. Placement of heating rod: For large fish, the heating rod should be fixed securely, because some large fish can easily knock it against the tank wall and break it with a tail flick. Do not bury the heating rod in the substrate, and do not directly contact the glass. Some fish friends have had the glass break due to uneven heating from direct contact. Place the heating rod diagonally or horizontally for better heat dissipation, even if it may not look good. Because heated water rises, a vertically placed rod has a relatively small temperature difference between the water generated at the bottom and the top, resulting in slower heat conduction, which undoubtedly reduces heating efficiency, prolongs heating time, and wastes energy. For clumsy fish like discus, it is best to add a sleeve to the
heating rod to prevent burns. If there are two heating rods in the tank, try to place them on both sides of the tank for even heating. The thermometer should be placed farthest from the heating rod to ensure the measured water temperature is not from the just-heated hot water.
4. It is best to have a backup heating rod at home. Otherwise, if the rod breaks at night, you won't have to panic.
5. The red light of the bimetallic strip heating rod does not indicate good working condition; the water temperature should be the standard. Because if the resistance wire is broken, the water temperature drops, the bimetallic strip closes the circuit, but it cannot heat, so the red light stays on for a long time. Of course, sometimes the temperature is reached, but the metal strip fails to disconnect, causing the temperature to continue rising, which may also manifest as a constant red light.
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
