JPH04240348A - Hot water feeder - Google Patents

Abstract

PURPOSE:To provide a hot water feeder not requiring any flame sensor device such as a prior art flame rod or the like in which a plurality of combustion burners are installed therein by a method wherein when one or all of the burners show a lost fire, a difference between a hot water feeding temperature got through a combustion heat at the combustion burners in advance and an actual hot water feeding temperature is calculated and then a presence or non-presence of lost fire at the burners is judged. CONSTITUTION:A heat exchanger 2 is disposed above a plurality of burners 1a and 1b. The heat exchanger 2 is provided with a water amount sensor 5, a water supplying thermistor 6 for sensing a water feeding temperature and a hot water feeding thermistor 7 for sensing the hot water feeding temperature. One burner is provided with a spark plug or electrode 8 so as to perform an ignition and combustion. The other burner is ignited through a transfer of fire from an initial ignited burner. When hot water supplying is carried out, a difference between a hot water set temperature T0 under an amount of combustion by a plurality of combustion burners 1a and 1b and an actual hot water temperature T1 of the hot water is calculated and a controller 9 is installed to judge a presence or a non-presence of the lost fire in the burners.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to combustion detection in water heaters using oil or gas as a heat source.

0002

2. Description of the Related Art In general, a water heater having a plurality of combustion burners is provided with an instantaneous heat exchanger 33 above the plurality of combustion burners 31 and 32, as shown in FIG. The water is heated by the combustion heat of the combustion burner. 34 is a water supply port, 35 is a hot water supply port, 36 is a water flow sensor that detects the flow rate to the heat exchanger 33, 37 is a water supply thermistor that detects the temperature of water supplied to the heat exchanger 33, 3
8 is a hot water supply thermistor that detects the temperature of hot water supplied from the heat exchanger 33, and each is attached to the heat exchanger 33. Further, the combustion burner is provided with a flame transfer guide 43, flame rods 39 and 40 for combustion detection, and an ignition electrode 41. 42 is a water heater controller.

0003

[Problems to be Solved by the Invention] In such a water heater having a plurality of burners 31 and 32, if the flame transfer guide 43 is fitted, the flame does not transfer from one burner to another, or one one combustion burner 31 or 32
If there is no combustion detection device, if the flame of the burner is extinguished due to the influence of wind speed or wind pressure, the fuel will blow out from the combustion burner and accumulate in the heat exchanger 33, resulting in explosive combustion and a very dangerous situation. Therefore, it is necessary to provide flame rods 39 and 40 for combustion detection in each of the combustion burners 31 and 32. This led to an increase in material costs and production man-hours, leading to an increase in product costs. Furthermore, since the frame rods 39 and 40 are constantly exposed to combustion flames, there is a problem in terms of durability. Therefore,
The present invention aims to provide a water heater that eliminates the frame rod, solves problems in terms of durability, and reduces product cost.

0004

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a water heater consisting of a plurality of combustion burners and a heat exchanger, in which the presence or absence of combustion flames of the plurality of combustion burners is determined by the hot water coming out from the heat exchanger. The state of combustion is determined by a controller based on the difference between the actual detected hot water temperature and the preset temperature of the hot water that is tapped based on the amount of combustion heat from the combustion burner.

[0005]

[Operation] With the above configuration, the present invention performs combustion with a plurality of combustion burners, and the detected temperature of the actual hot water discharged from the heat exchanger and the preset temperature of the hot water based on the combustion heat amount of the combustion burners are set in advance. The difference is used to determine whether there is a flame or not.

[0006]

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the figure, two combustion burners 1a, 1
An instantaneous heat exchanger 2 is provided above b, and water is heated in this heat exchanger 2 by the combustion heat of combustion burners 1a and 1b. Reference numeral 3 denotes a water supply inlet, 4 a hot water supply inlet, 5 a water flow sensor for detecting flow rate, 6 a water supply thermistor for detecting water temperature, and 7 a hot water supply thermistor for detecting hot water temperature, which are each attached to the heat exchanger 2. Also, combustion burner 1
An ignition electrode 8 is provided at the ignition electrode 8, and after igniting the combustion burner 1a, the flame transfer guide 10 causes the flame to transfer to the adjacent combustion burner 1b. Reference numeral 9 denotes a controller for the water heater, and this controller receives the signal from the water supply thermistor 6 that detects the temperature of the water supplied to the heat exchanger 2, and the water temperature set by the user.
The combustion burners 1a, 1b control the signals from the hot water supply thermistor 7 and the water amount sensor 5 in accordance with the amount of hot water, and at the same time calculate the difference between the set temperature of hot water to be tapped and the actual hot water temperature to be tapped based on the amount of combustion heat. Detects the presence or absence of combustion flame.

In the above configuration, a plurality of combustion burners 1a
, 1b, the combustion burners 1a, 1b
If one or both of the flames are extinguished for some reason (blown out by wind or a malfunction in the flame transfer guide 10), the hot water temperature of the hot water thermistor 7 of the heat exchanger 2 will change as shown in Figure 2. Detection temperature T1 and combustion burner 1a,
The controller calculates the set temperature T0 in advance from the amount of combustion heat obtained during combustion of 1b, the temperature of the supplied water, and the amount of water, and the difference ΔT is generated. Therefore, the detected hot water temperature becomes lower than the set temperature, and the detected hot water temperature becomes T2. As described above, under normal conditions, the set temperature T0 and the detected hot water temperature temperature T1 are approximately equal, and when the combustion flame is extinguished, the set temperature T0 and the detected hot water temperature T1 become T2, giving a difference of ΔT. By setting the range of the difference in ΔT in advance, it is possible to determine the presence or absence of a flame, thereby eliminating the need to set a flame rod for combustion detection in each burner.

[0008]

[Effects of the Invention] As is clear from the above embodiments, according to the water heater of the present invention, the controller that determines combustion detection based on the difference between the detected hot water temperature and the set hot water temperature controls the combustion in the plurality of combustion burners. Since combustion can be detected without the need to individually set up detection flame rods, it is possible to provide a water heater that can reduce material costs and production man-hours.

[Brief explanation of the drawing]

[Fig. 1] A configuration diagram of a water heater in an embodiment of the present invention.

[Figure 2] Graph showing the relationship between the hot water temperature setting and the hot water temperature detection temperature in the same example

[Figure 3] Configuration diagram of a conventional water heater with multiple burners

[Explanation of symbols]

1a, 1b Combustion burner 2 Heat exchanger 5 Water level sensor 6 Water supply thermistor 7 Hot water thermistor 8 Ignition electrode 9 Controller

Claims (1)

[Claims] Claim 1: A plurality of combustion burners, a heat exchanger that converts water heated by the combustion burners into hot water, a hot water thermistor provided on the hot water supply side of the heat exchanger, and a hot water temperature detected by the hot water thermistor. A water heater comprising: a controller that calculates a difference between a detected temperature and a preset hot water temperature based on the combustion amount of a plurality of combustion burners set in advance, and detects the presence or absence of combustion flames of the combustion burners.