JPH0348425B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas instantaneous water heater, a so-called gas proportional instantaneous water heater, in which the water supply temperature is controlled by the amount of gas.

More specifically, the present invention relates to an ignition control system for a gas proportional instantaneous water heater.

To ignite a conventional gas proportional instantaneous water heater, a water flow switch is installed in the water supply pipe, and this water flow switch is turned on.
When it reaches the point of ignition, the ON/OFF status of the water flow switch is determined by the differential pressure at the water flow switch and the amount of water.

That is, when the differential pressure at the water flow switch exceeds a certain level or the amount of water flowing exceeds a certain level, the burner is ignited.

Such conventional devices have the following problems.

That is, the condition is 1. It is a gas proportional instantaneous water heater and has a proportional band of No. 4 to No. 16.

2 The temperature setting is set to 70℃ for high temperature and 35℃ for low temperature.

3 Inlet water temperature is 5℃ to 25℃ 4 When the minimum flow rate required for operation with a conventional water flow switch is about 3.0/min, (a) If the set temperature is set to high (70℃), the inlet water temperature Assuming 5℃, No. 4 outputs 100 Kcal/min as heat, so 100/(70-5) = 1.54/min - (70-5) x 3 = 195 Kcal/min - 195/25 = No. 7.8 - From the formula, under the above conditions, the water heater is 1.54
Even though it has the ability to start a fire with a flow rate of /minute, the minimum flow rate for switch operation is
Since it is determined to be 3.0/min, there is an unusable area shown by the diagonal line in the graph of Figure 3, and in reality, according to the formula, only No. 7.8 can catch fire.

Therefore, it may not be possible to use small amounts of hot water in winter.

(b) When the set temperature is set to low (35℃) and the inlet water temperature is 25℃, 100/(35-25) = 10/min - (35-25) x 3 = 30Kcal/min - 100/3 = 33.3℃ ∴25 + 33.3 = 58.3℃ − According to the formula, a flow rate of 10/min is required to obtain hot water at 35℃, but in reality, according to the formula, a fire starts at 3.0/min and the From Figure 3, the temperature rise will be 33.3°C, which is the intersection of the water heater's minimum capacity line a and the 3.0/min line b, and from the formula, the hot water temperature will be 58.3°C.

Therefore, in the summer, when you want to use a small amount of lukewarm water, you can actually only use hot water, which poses a risk of burns.

Secondly, it was impossible to connect to solar power using a regular water flow switch. The reason is that if water flows over 3.0/min, a fire will definitely start, so if hot water comes in, the fire will continue to burn at the lowest number no matter how high the temperature rises, so the water will boil. The safety device will work and put out the fire. That is 80
When hot water at ℃ comes in, if the lowest capacity is set to 4 and the amount of hot water is 3/min, the temperature rises by 100Kcal/min/3/min = 33.3℃, and the outlet temperature is 80 + 33.3 =
The temperature will be 113.3℃.

The purpose of the present invention is to solve the problems (a) and (b) above, and to make it possible to use small amounts of hot water even in winter, while
To provide a gas instantaneous hot water heater which does not pose the danger of hot water coming out when trying to use a small amount of low temperature water in the summer and can also be connected to a solar water heater.

In order to achieve the above object, the gas instantaneous water heater of the present invention uses a water flow sensor and a water temperature sensor respectively installed in the water supply pipes, and the detected values of these sensors and a set temperature preset by a temperature setting device. A calculation means for calculating the required output amount, a comparison means for comparing the calculated required output amount with the minimum capacity of the water heater, and as a result of the comparison by the comparison means, the calculated output amount is greater than or equal to the minimum capacity of the water heater. an output generating means that generates an output when the gas is supplied, a solenoid valve that is installed in the gas supply pipe and opens upon receiving the output from the output generating means, and an ignition device that is installed near the burner and operates to ignite upon receiving the output from the output generating means. It is equipped with the following.

In a gas water heater configured as described above, if the required output amount calculated from the three elements of water input amount, set temperature, and input water temperature is greater than or equal to the minimum capacity of the water heater, a switch is activated to turn on the burner. ignite.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In the figure, 1 is a water heater, fuel gas is sent to a burner 3 via a gas supply pipe 2 and burned there, and water enters a heat exchanger 5 via a water supply pipe 4, where it is heated. The hot water passes through a hot water supply pipe 6 and is supplied to a required faucet 7.

The gas supply pipe 2 includes a sequential solenoid valve 8 from the upstream side.
A governor 9 and a gas proportional valve 10 are provided, and the water supply pipe 4 is provided with a water amount sensor 11 and a water temperature sensor 12 with the former on the upstream side.

The main solenoid valve 8, the gas proportional valve 10, the water flow sensor 11, and the water temperature sensor 12 are each electrically connected to the controller 13. The inlet water temperature is detected and a signal B is sent to each controller 13.

On the other hand, the controller 13 is provided with an ON/OFF switch 14 for turning ON/OFF the operation of the water heater, and a temperature setting device 15.

Then, the controller 13 turns on the switch 14.
By turning ON, the flow rate Q detected by the water flow sensor 11 and transmitted by the signal A, the inlet water temperature Tc detected by the water temperature sensor 12 and transmitted by the signal B, and the set temperature set by the temperature setting device 15. Calculate Ts using the formula Q x (Ts - Tc) / 25 = number -, and if the value is greater than the minimum capacity of the water heater, the original solenoid valve 8 and ignition device 16
Send signal C to. The ignition device 16 comprises a conventionally known igniter or the like, and is provided near the burner 3 facing the burner 3.

The main solenoid valve 8 is opened by the signal C, and the ignition device 16 emits a spark toward the burner 3, which ignites and operates.

Further, the controller 13 sends a signal D to the gas proportional valve 10 based on the required amount of heat calculated from the above-mentioned flow rate, inlet water temperature, and set temperature.

The gas proportional valve 10 changes its opening degree based on the signal D, increasing or decreasing the amount of gas sent to the burner 3.

Incidentally, the gas proportional valve 10 may be configured such that a hot water outlet temperature sensor is provided in the hot water supply pipe 6, and the required amount of heat is calculated based on the difference between the outlet hot water temperature detected by the hot water outlet temperature sensor and the set temperature to control the gas amount. It is possible.

Since the present invention has the above configuration, it has the following advantages.

(1) If the required output amount calculated from the three elements of water volume, water input temperature, and set temperature is greater than or equal to the minimum capacity of the water heater, ignition will occur, so regardless of the water input temperature, a small amount of high-temperature water can be used. , it will be possible to use hot water at a low temperature setting, and it will also be possible to connect to solar power.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention.
Fig. 2 is a schematic diagram of a gas instantaneous hot water supply system showing an outline of an embodiment of the present invention, and Fig. 3 shows the ignition operating line of the gas instantaneous hot water supply system of the present invention and a conventional gas instantaneous hot water supply system. It is a graph, where a is the minimum capacity line of the water heater, that is, the ignition operating line in the present invention, and b
indicates the ignition operating line in the conventional type. 1: water heater, 2: gas supply pipe, 3: burner,
4: Water supply pipe, 8: Original solenoid valve, 11: Water amount sensor, 12: Water temperature sensor, 15: Temperature setting device,
16: Ignition device.

Claims (1)

[Claims] 1 A gas instantaneous water heater that controls the hot water temperature by the amount of gas, with a water flow sensor and a water temperature sensor installed in each water supply pipe, and settings preset by the detected values of these sensors and a temperature setting device. A calculation means for calculating the required output amount from the temperature; a comparison means for comparing the calculated required output amount with the minimum capacity of the water heater; and as a result of the comparison by the comparison means, the calculated output amount is An output generating means that generates an output when the capacity is higher than the minimum capacity, a solenoid valve that is installed in the gas supply pipe and opens when it receives the output from the output generating means, and a burner that is installed near the burner and opens the valve when it receives the output from the output generating means. A gas instantaneous water heater characterized by comprising an ignition device that operates to ignite the water.