Gas water heaters can be divided into direct-exhaust gas water heaters and strong-exhaust gas water heaters according to the different ways of exhaust gas emission after combustion. The main characteristic of direct-exhaust gas water heater is that while burning hot water, the exhaust gas is directly discharged into the air. In this way, in the case of closed rooms, it is easy to cause harmful gas accumulation and lack of oxygen, leading to personal poisoning, which is harmful to health, and serious casualties.

Most consumers know the difference between electric water heater, gas water heater and solar water heater, but they do not know that the most commonly used gas water heater has different exhaust modes. It is understood that China's "National Standard for Domestic Gas Water Heaters" divides gas water heaters into flue type, strong exhaust type and balanced type, which are mainly classified according to the way of feed and exhaust. Yao Kenong, director of the National Gas Appliances Quality Supervision and Inspection Center, said: Consumers should have a better understanding of the different ways of gas water heater supply and exhaust, so as to make targeted choices and ensure safe use.

Flue type: high potential safety hazard

"More than 90% of the safety accidents of gas water heaters in China are caused by flue water heaters." Yao Kenong pointed out that the safety problems of flue water heaters are mainly caused by incorrect installation and use. It is understood that flue water heater is based on the principle of aerodynamics to exhaust the burned exhaust gas outdoors. If the user closes doors and windows while bathing, the exhaust gas generated by the water heater can not be effectively discharged outdoors, which can easily lead to safety accidents.

"But this kind of gas water heater also has one advantage, that is, the price is low." It is understood that the key to the safe use of flue gas water heater is to exhaust the flue gas completely outdoors. Therefore, consumers must purchase flue gas pipe when purchasing water heater and install it according to the stipulated requirements. "However, in terms of ensuring user safety and environmental protection, flue water heaters will gradually withdraw from the market in the future."

Strong row: the mainstream of the current market

Compared with flue gas water heater, strong exhaust gas water heater is more reliable. At present, most of the mainstream gas water heater products on the market belong to "strong exhaust type".

However, experts warn consumers that the oxygen required for the combustion of the strong exhaust water heater is still taken from the indoor, while some manufacturers reduce the number of heat exchangers in order to reduce costs, which may cause high exhaust temperature, which may lead to the combustion deterioration of the flue when blocked, and make the carbon monoxide in the flue gas rise sharply. "For safety, this type of water heater is best installed in the kitchen or balcony."

Balanced: safer and more expensive

Balanced gas water heater is the safest gas water heater at present. Compared with the former two types of water heaters, the biggest difference of the balanced gas water heater is that it can form a sealing system with matching flues, that is, it does not consume indoor air, nor does it cause smoke pollution.

It is understood that, in addition to the electric water heater, only the balanced gas water heater is the only one allowed to be installed in the bathroom in the national standard. Experts said: "From the development of water heaters in Japan, Europe and the United States, the balanced water heater is the trend of development, but also the trend of international water heater development. It is safe to install the balanced gas water heater in the bathroom. However, when interviewed by reporters at home appliance stores, we found that most of the current balanced gas water heaters are foreign high-end brands, and their prices are much more expensive than flue-type ones.

What is the difference between direct and forced gas water heaters?

Strong exhaust fan, 220V power supply, exhaust exhaust exhaust outdoor; direct exhaust fan, battery, some exhaust gas in the indoor. Both of them consume indoor oxygen and cannot be installed in the bathroom.

Straight row JSD: The oxygen required for combustion is taken from the chamber, and the exhaust gas generated after combustion is also discharged into the chamber. The production and sale of such products have been strictly prohibited in countries with great risks.

Strong exhaust JSQ: The exhaust gas generated after combustion is forced out of the room by the fan in the machine through the flue. This product is safe.