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Home Service FAQs FAQ of gas-fired(oil-fired) boilers What is the difference between condensing boiler and non-condensing boiler?

What is the difference between condensing boiler and non-condensing boiler?

10 Jun 2022

Condensing boiler and non-condensing boiler are two main types of gas-fired boilers on the market at present. A correct understanding of the difference between condensing boiler and non-condensing boiler can help you choose a reasonable type. Before introducing the difference between them, it is necessary to introduce the principles of condensing boiler and non-condensing boiler.

 

Introduction of working principle of non-condensing boiler

Non-condensing boiler is a kind of heat energy conversion equipment, which uses natural gas, liquefied gas, city gas and other gas fuels, and burns and releases the energy in the boiler to heat the water in the boiler and vaporize it into steam. Principle: Water is constantly heated by the energy released by the combustion of gas fuel in the boiler, and the temperature rises to produce pressurized steam. As the boiling point of water rises with the increase of pressure, the boiler is sealed, and the expansion of water vapor in the boiler is limited to generating pressure to form thermal power (strictly speaking, boiler water vapor is formed by heating water in the boiler at a constant pressure until saturated water is vaporized), which is widely used as an energy source.

 

Introduction of working principle of condensing boiler

The working principle of the condensing boiler is to recover the energy of the hot flue gas (generally around 140℃) emitted by the boiler through a certain device. The temperature of the recovered flue gas is only around 60℃, so that the thermal efficiency is increased by about 10%, which naturally saves about 10% of the gas. At the same time, in the process of energy recovery, it can also reduce the emission of harmful gases and environmental pollution. In terms of working principle, the difference between condensing boiler and non-condensing boiler lies in the flue gas treatment part.

 

Difference between condensing boiler and non-condensing boiler

1. Exhaust temperature

In non-condensing boilers, the exhaust gas temperature is generally 160~250℃, or even higher, which makes the water generated during fuel combustion in the flue gas overheat, and the steam will be lost from the chimney along with the flue gas. The thermal efficiency of traditional boilers can only reach 85%~91%. The condensing boiler reduces the exhaust temperature to 50~70℃, fully recovers the sensible heat in the flue gas and the condensation latent heat of water vapor, and greatly improves the thermal efficiency. This is also the difference between the core condensing boiler and non-condensing boiler.

2. Material and combustion mode

The heating area of the condensing boiler is that the main heat exchanger and flue gas channel of the boiler body are changed to corrosion-resistant materials, and the original combustion mode of the combustion system is changed to the proportional combustion mode to ensure the stability and high efficiency of combustion. Furthermore, the method of frequency conversion and continuous water supply is adopted to ensure that the temperature of the tail heating surface is greatly lower than the exhaust gas temperature, with large temperature difference, large heat exchange area and good heat exchange effect. The exhaust gas temperature of the boiler can be reduced to below 80℃m, and the loss of exhaust gas is the main heat loss of the boiler, so the thermal efficiency of the boiler has been greatly improved.

3. Boiler structure

The horizontal structure of two-stage condenser is installed, and two-stage spiral finned tube condenser is arranged outside, and the heating surface is doubled. The vaporized water vapor at the exhaust of the boiler is mostly condensed below the liquid point to form condensed water, which has a lower exhaust temperature and higher thermal efficiency. Under the condition of condensation and recovery, the thermal efficiency of the boiler is high.

4. Burner

The working mode of the condensing burner of the boiler is that it can stay at any point in the working range, and the output of the burner can be balanced with the heating requirements of the system at any time.

 

These are the difference between condensing boiler and non-condensing boiler. You can find that the thermal efficiency of condensing boiler is greatly improved and the operating cost is lower. On the other hand, the purchasing cost of condensing boiler is also higher, so users need to choose it reasonably.

ZOZEN Boiler has been striving for more than 30 years, always taking technological innovation as an inexhaustible motive force for enterprise development, and has gradually become a leader in industrial boiler manufacturing industry. In the application of condensation technology, ZOZEN Boiler has the research and development achievements of steam boiler condensate recovery and utilization device. Through the application of advanced technology, the exhaust gas temperature of ZOZEN gas boiler can be reduced to below 60 degrees, and the thermal efficiency can reach above 98%, which further improves the utilization rate of fuel, and the effect of energy saving and environmental protection is remarkable. Welcome to consult online.

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