JP5165605B2 - Latent heat recovery type water heater - Google Patents

Description

  The present invention relates to a latent heat recovery type water heater having a drain neutralization tank that neutralizes and drains strongly acidic drain.

  Conventionally, in this type, drain water generated when the temperature of the exhaust gas drops below the dew point due to heat exchange between the exhaust gas after combustion and the latent heat exchanger is replaced by a neutralizer filled with a neutralizing agent. The product was neutralized and drained by circulating it.

JP 2001-272110 A

  By the way, in this conventional one, the drain neutralization tank is in communication with the exhaust path via the inlet, so that the exhaust gas flowing into the drain neutralization tank from the inlet flows out of the drain pipe as it is until the drain accumulates. It has been a problem that it is released into the equipment and outdoors and causes odor.

  In order to solve the above-mentioned problems, the present invention is particularly configured in such a manner that the flow sensor provided in the hot water supply pipe detects the flowing water, so that combustion is started along with combustion of this combustion burner and combustion of this combustion burner. A combustion fan that supplies air and exhausts exhaust gas, a secondary heat exchanger that exchanges heat with the exhaust gas and recovers latent heat, and collects and neutralizes the drain generated by the heat exchange of the secondary heat exchanger A drain pipe connected to the drain neutralization tank is provided with an open / close means for opening / closing the drain pipe, and the open / close means detects a flowing water by a flow sensor. It is intended to be closed by.

  As described above, according to the present invention, when the combustion burner is not combusting, the drain pipe is opened by the opening / closing means, the neutralized drain is discharged, and the flowing water is detected by the flow sensor that starts combustion. Since it is closed at the same time as the start of combustion, the opening and closing means are closed without delay to the generation of exhaust gas, and the release of exhaust gas through the drain neutralization tank is surely prevented, so that no odor is generated. It is to make.

The schematic block diagram of one Embodiment of this invention. Explanatory drawing of the exhaust path. The block diagram of the principal part electric circuit. Explanatory drawing of the drain neutralization tank.

Next, an embodiment of the present invention will be described with reference to the drawings.
1 is a main body of a water heater, and a combustion chamber 4 having a gun-type combustion burner 2 and a combustion fan 3 mounted downward at the upper end is provided inside, and the combustion chamber 4 further includes a combustion chamber 4. A primary heat exchanger 5 for recovering sensible heat of exhaust gas is provided.

  6 is a communication path that communicates the bottom of the combustion chamber 4 with one end, and an exhaust path 8 that has an exhaust port 7 at the top communicates with the other end. The exhaust gas from the combustion chamber 4 is U-turned through the communication path 6 and exhausted. The air is discharged from the exhaust port 7 by the blowing force of the combustion fan 3 through the path 8.

  The exhaust path 8 is partitioned by a first partition plate 9 upward from a lower communication path 6 and a second partition plate 11 and communicates only with the first flow path 10 above, The second flow path 12 through which the exhaust gas flows downward from the second flow path 12, and the second flow path 12 communicates only in the lower part, and the third flow path 13 through which the exhaust gas directed from the lower part toward the upper exhaust port 7 flows, A three-layered meandering path is formed in the thickness direction.

  14 is a secondary heat exchanger for recovering the latent heat of the exhaust gas provided in the second flow path 12, and is connected to the primary heat exchanger 5 and the water intake pipe 15. The heated water is supplied to the primary heat exchanger 5, further heated, and discharged as hot water from a hot water supply pipe 16 communicating with the primary heat exchanger 5.

  Reference numeral 17 denotes a hot water supply control circuit constituted by a microcomputer, which is connected to a remote controller 18 provided in the kitchen or the like, and a hot water supply thermistor provided in the hot water supply pipe 16 so that the hot water supply temperature becomes a hot water supply set temperature set by the remote controller 18. 19 is used to control the amount of combustion of the combustion burner 2 according to the detected temperature 19. The hot water supply control circuit 17 detects the flowing water by the flow sensor 20 that is also provided in the hot water supply pipe 16. The combustion burner 2 starts combustion with the start of driving.

  21 is a drain neutralization tank provided in the lower part of the exhaust path 8, which collects strongly acidic drain water generated by latent heat recovery by the secondary heat exchanger 14, neutralizes it, and drains it from the drain pipe 22. The bottom plate 23 of the exhaust path 8 is inclined, a collecting pipe 24 communicating with the drain neutralizing tank 21 is attached to the lowest part thereof, and the drain pipe 22 is further provided with an opening / closing means 25 comprising an electromagnetic valve. The open / close means 25 detects the flowing water by the flow sensor 20, is energized and closed via the hot water supply control circuit 17, and closes the drain pipe 22, thereby capturing exhaust gas generated by combustion of the combustion burner 2. A signal that prevents the flow sensor 20 from detecting flowing water and stops the combustion of the combustion burner 2 by the hot water supply control circuit 17 in order to prevent discharge through the collecting pipe 24, the drain neutralization tank 21, and the drain pipe 22. Open and close hands 25 be stopped energized opens the drain pipe 22 is for discharging the neutralized drain accumulated during combustion.

  The drain neutralization tank 21 is preliminarily filled with a neutralizing agent 26 made of calcium oxide. The drain neutralization tank 21 is provided with a drain water inlet 27 communicating with the collecting pipe 24 at one side wall upper portion and at the other side lower portion. A drain water outlet 28 is provided at a position lower than the inlet 27, and in the drain neutralization tank 21 between the inlet 27 and the outlet 28, the end communication portions 29 are alternately arranged. The four partition plates 30 are provided in the vertical direction, and the contact time between the drain and the neutralizing agent 26 is lengthened so that the neutralization is satisfactorily performed.

Next, the operation of this embodiment will be described.
When a hot water tap (not shown) at an appropriate location is opened and hot water supply is started, the flow sensor 20 detects the flow of the hot water and the combustion fan 3 is driven via the hot water control circuit 17 so that the combustion burner 2 Starts combustion, exhaust gas generated by this combustion makes a U-turn from the combustion chamber 4 through the communication path 6 and flows into the exhaust path 8, and flows through the second flow path 12 of the exhaust path 8 from above to below. Thus, heat is exchanged with the feed water flowing into the secondary heat exchanger 14 and exhausted from the exhaust port 7.

  The hot water whose temperature has risen in the secondary heat exchanger 14 flows into the primary heat exchanger 5, where it is further heated by heat exchange with the exhaust gas generated by the combustion of the combustion burner 2, and discharged from the hot water tap as hot water. The combustion amount (thermal power) of the combustion burner 2 at this time is detected by the hot water thermistor 19 provided in the hot water supply pipe 16 exiting the primary heat exchanger 5, and this temperature is determined by the user himself / herself. Is adjusted to a hot water supply set temperature set by the remote controller 18.

  Next, the drain water generated by the latent heat recovery of the feed water and exhaust gas flowing through the secondary heat exchanger 14 in the second flow path 12 of the exhaust path 8 is suppressed downward by the exhaust gas flow from above to below. The neutralization which flows along the inclined bottom plate 18 and flows into the drain neutralization tank 21 from the collection pipe 24 and fills the small chamber partitioned by each partition plate 3. The agent 26 is neutralized well by contacting with the agent 26 over time.

  At this time, the opening / closing means 25 provided in the drain pipe 22 communicating with the outlet 28 of the drain neutralization tank 21 inputs a signal of detection of flowing water by the flow sensor 20 to the hot water supply control circuit 17. A combustion start signal is output from the control circuit 17 to the combustion burner 2 and the combustion fan 3, and at the same time, the drain pipe 22 is closed by receiving an energization start signal, that is, combustion in which exhaust gas is generated. Sometimes the drain pipe 22 is closed to reliably prevent the exhaust gas from being discharged through the collection pipe 24, the drain neutralization tank 21, and the drain pipe 22, and to prevent the generation of odor due to the leak of the exhaust gas. During this time, the drain is stored in the drain neutralization tank 21.

  Further, the opening / closing means 25 inputs a signal indicating that the flowing water is not detected by the flow sensor 20 to the hot water supply control circuit 17, so that the hot water supply control circuit 17 receives the energization stop signal simultaneously with the combustion stop signal and receives the drainage pipe 22. As a result, the neutralized drain stored in the drain neutralization tank 21 is drained from the drainage channel at once through the drainage pipe 22, thereby reducing the consumption of the neutralizing agent 26. , Foreign matter such as cocoons and algae are difficult to deposit inside. In addition, it is possible to prevent freezing without using an electric heater or the like.

2 Combustion burner 3 Combustion fan 14 Secondary heat exchanger 16 Hot water supply pipe 17 Hot water supply control circuit 20 Flow sensor 21 Drain neutralization tank 22 Drain pipe 25 Opening and closing means

Claims (1)

  A flow sensor provided in the hot water supply pipe detects flowing water, and thereby a combustion heater that starts combustion, a combustion fan that is driven along with combustion of the combustion burner to supply combustion air and exhaust gas, and the exhaust gas A secondary heat exchanger that performs heat exchange with the secondary heat exchanger, and a drain neutralization tank that collects drain generated by heat exchange of the secondary heat exchanger and drains it after neutralization. The drainage pipe connected to the drain neutralization tank is provided with opening and closing means for opening and closing the drainage pipe, and the opening and closing means is closed by detecting flowing water by a flow sensor.

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