Nowadays, when people buy electric water heaters, they are paying more and more attention to safety. How can the electric water heater manufacturer not know this? If you don’t believe it, look at the products on the market today. All of them are superimposed with various safety devices.
However, there are two safety technologies that have been around for many years, but few products use them: water and electricity separation and water and power outage. The names of these two technologies make people feel safe enough. Why are they so unpopular? Today, let’s talk about this issue.
The cost of water and electricity separation is high
The water and electricity separation electric water heater is actually an electric water heater made into an induction cooker:
A general electric water heater puts one (or more) heating rods inside the inner tank. Heating rod, you can understand it as the "fast heating" that we usually use to boil water.
Water and electricity separation in the standard sense is to install an induction cooker on one side of the electric water heater (let's think of it as an induction cooker). The inner pot on the other side is equivalent to a metal pot. Through electromagnetic induction , the water in the inner tank is heated.
Electric water heaters like this were sold by some small brands in the past few years, but now they are hard to find. Its biggest problem is high cost and low efficiency - in terms of cost, the cost of induction cookers is definitely much higher than that of heating faster; in terms of efficiency, the loss caused by electromagnetic induction is bound to be much higher than the direct heat conduction of the heating rod. This not only increases power consumption, but also causes the heating speed to become very slow.
is expensive, consumes electricity, and slow to boil water. Various unfavorable factors have resulted in it not being accepted by consumers.
The water and electricity separation that can be purchased now is another form:
It uses a shell to cover the heating rod, so that even if the heating rod leaks electricity, it will not leak into the water. However, this shell will inevitably affect heat transfer, resulting in reduced efficiency.
Therefore, so far, electric water heaters that use this form of water and electricity separation are still relatively rare.
It is not practical to cut off the power when water comes out.
Install a water flow monitoring device at the water outlet of the water heater. As long as water is used, the monitoring device will automatically send out a signal and cut off the power supply. In this way, the purpose of "cutting off the power supply by yourself while using water" is achieved.
This form of security device seems to be quite reliable, but unfortunately it is still difficult to be accepted by the market:
On the one hand, this form is not stable. Monitoring devices are easily damaged. For example, the temperature sensor failure of an air conditioner is one of the most common failures of air conditioners.
Therefore, electric water heaters with water outages and power outages often have the problem of "power is cut off when there is no water" or "power is not cut off when water is used".
On the other hand, this kind of electric water heater cannot heat water at the same time.
You must know that "plugging in for bathing" is precisely the main development direction of electric water heaters now. Everyone attaches so much importance to safety, and the purpose is also to keep taking showers with electricity. Otherwise, just unplug it. What safety device is needed?
The advantage of plug-in bathing is that it can expand the amount of hot water:
The biggest problem with electric water heaters is that they have limited capacity and cannot provide unlimited hot water like gas water heaters . Today's electric water heaters are upgraded in terms of power and heating rod shape to increase the heating speed.
also adds safety devices to make plug-in washing possible. In this way, you can continue to heat the water during the bath. It is entirely possible for a 60L electric water heater to release more than 300L of warm water (heated washing + high temperature setting).
Common safety devices
At present, the most common safety measures on electric water heaters are the following:
1. Anti-electricity wall. Some brands are called " electric isolation wall ". In fact, the principles are the same. Increase the resistance of water through long and thin pipes. As the resistance increases, the current will decrease. Anyone who has attended junior high school knows this. Once the water flow is charged, it can reduce the leakage circuit and reduce the chance of electric shock to the human body.
2. Leakage plug, there are many buttons on the plug. When the electric water heater leaks electricity, the leakage plug will cut off the power supply immediately.This plug is equivalent to a switch and has the function of breaking the circuit. Generally, when the leakage current exceeds 15mA or 20mA, the plug will automatically trip.
3. The electronic safety device is very similar to the water outlet and power outage. A monitoring device is installed at the water outlet. The difference is that the monitoring device here only monitors the current and automatically cuts off the power supply when the water flow is found to be charged, ensuring the safety of electricity use. The stability of the monitoring device is not high, so it is impossible to have only this kind of safety device on an electric water heater.
4. Installation requirements. Anyone who has installed an electric water heater in the past two years will find that the current installation requirements are much higher than before. The installation worker will test the home circuits, including wires, ground wires, sockets, leakage switches, etc. If there is any disqualification, the workers will refuse to provide you with installation services, which will fundamentally reduce the possibility of leakage of the electric water heater.
