JPS5852930A - Combustion apparatus - Google Patents

Abstract

PURPOSE:To hold high efficiency of the subject apparatus even when the outer air is dry by causing condensed water from a heat exchanger for condensation to flow down in a combustion air supply passage. CONSTITUTION:A combustion air supply passage 5 to a burner 4 is provided at the lower part of a primary heat exchanger 1, and an outlet of a condensed water receiver 3 from the heat exchanger for condensation is arranged in the vicinity of the inlet of the combustion air passage 5. Reference numeral 7 designates a combustion fan; and 6, a condensed water outlet provided at the lower part of the air supply passage 5. By this construction, the water content within the combustion air increases, and the quantity of recovered latent heat increases.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims at high efficiency and relates to a combustion device that can be applied to a hot water heater or hot water heater that uses a condensing heat exchanger.

In recent years, there has been a call for energy conservation, and a highly efficient combustion device is required. Conventionally, the efficiency of combustion 'd"i:r shells was around 80φ at most, and if the efficiency was higher than that, condensed water would adhere to the heat exchanger, so due to durability issues, the efficiency was limited to the extent that condensed water would not adhere to the heat exchanger. However, considering the recent trend toward energy conservation, there is a movement to increase the efficiency to over 90 cm by not only capturing the sensible heat of combustion exhaust gas as in the past, but also recovering heat other than latent heat. is coming out.

That is, conventionally, as shown in FIG. 3, the primary heat exchanger 1
A condensing heat exchanger 2 for latent heat recovery is placed in 1-, and a secondary heat exchanger 2 is placed above the primary heat exchanger 1 and below the condensing heat exchanger 2. A condensed water receiver 3 is provided to receive condensed water coming out of the tank and prevent it from falling into the primary heat exchanger 1. At this time, the combustion exhaust gas is directed to exit through the path shown by the arrow in Figure 3. The configuration shown in Figure 3 is
It is relatively easy to make by attaching a condensed water heat exchanger on top of a conventional device, but with the aim of achieving high efficiency,
In order to ensure heat exchange of 0φ or more, it was necessary to consider changes in the environment. This means that the heat exchange efficiency is second
As shown in the figure, it is based on the fact that the humidity of the combustion air decreases as the humidity decreases.

An object of the present invention is to take into consideration the influence of the humidity IJf of combustion air so as not to cause a decrease in efficiency even if the outside air is dry.

In order to achieve the above object, the present invention has a basic configuration in which condensed water discharged from a condensing heat exchanger is passed through an air supply path through which air is supplied to the noner, and with this configuration, It supplies the steam latent heat of the combustion air.

An embodiment of the present invention will be described below with reference to FIG.

4 is a burner, 5 is an air supply path for supplying air to the burner 4, and the outlet of the condensed water receiver 3 from the condensing heat exchanger 2 is arranged near the input of the air supply path 60. Furthermore, a condensed water outlet 6 is provided at the bottom of the air supply path 6. 7 is a futon that supplies combustion air.

Next, the operation will be explained.

Combustion air supplied from the fan 7 is supplied to the bar 4 in the direction of the arrow, and combustion takes place. The heat obtained from combustion is transferred to the primary heat exchanger1. The condensing heat exchanger 2 exchanges heat and is used as a water heater or hot water heater.At this time, in the condensing heat exchanger 2, water vapor in the combustion exhaust gas condenses, and the condensed water Condensed water receiver 3
and is led to the air supply path 6. Here, the L condensed water is mixed with combustion air and supplied to the burner 4 again. At this time, the combustion air has a considerably high degree of saturation, and the water vapor content in the combustion air has increased.

Therefore, the dew point temperature of the combustion exhaust gas is almost determined by the temperature of the water passing through the condensing heat exchanger 2 (water pipes etc. are not shown here), so the more water vapor in the combustion air, the more water vapor there is in the combustion air. The amount of condensed water increases, the amount of latent heat recovered increases, and efficiency improves.

As is clear from the above description, the combustion appliance of the present invention provides the following effects.

(1) In conventional combustion devices that aim for high efficiency and recover latent heat, the efficiency differs depending on the amount of water vapor contained during combustion. Therefore, efficiency decreases on days with low humidity. In contrast, according to the present invention, since condensed water from the combustion exhaust gas is added to the combustion air, it is possible to constantly supply combustion air with a high degree of water vapor saturation to the burner. Stable and highly efficient combustion can be achieved without being affected by the environment.

(2) Conventional latent heat recovery type combustion devices discard the heat of the condensed water, but in the present invention, the heat of the condensed water can be recovered as latent heat, thereby improving combustion efficiency.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a combustion appliance according to an embodiment of the present invention, FIG. 2 is a diagram showing the relationship between combustion efficiency and humidity of combustion air, and FIG. 3 is a schematic diagram of a conventional combustion device. 2...Condensing heat exchanger, 4......(-
6... Air supply path. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
θ fO/θθ outside of Figure 2 Figure 3

Claims (1)

[Claims] A burner, a condensing heat exchanger for exchanging heat with the combustion gas of the burner, and an air supply path through which air is supplied to the burner, and the condensed water discharged from the condensing heat exchanger is supplied to the air. A combustion appliance designed to pass through the road.