JPH052894B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a hot water heater that circulates hot water to a radiator to provide effects such as heating bathtub water or drying clothes. Conventional configurations and their problems Conventional hot water heaters, for example, in which a temperature sensor is installed at the outlet of a heat exchanger, operate to maintain a constant temperature of hot water sent to the radiator regardless of the required heat load. This is common. Purpose of the Invention Therefore, it is an object of the invention to realize a hot water heater that circulates high-temperature water when the heat load is large, and circulates relatively low-temperature water when the heat load is small. Structure of the Invention In other words, when performing heating operation, the heat load is large because the room is cold at the beginning of operation, and it is desirable to circulate high-temperature water to the radiator to speed up the rise in room temperature. When the heat load becomes small, it is advantageous to lower the temperature of the circulating hot water to reduce heat radiation loss from the heating pipes in terms of improving operational efficiency. Therefore, a temperature sensor is installed upstream of the hot water heating path outlet of the heat exchanger.
This configuration includes a combustion control device that continuously controls the amount of fuel supplied based on the signal. DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an example in which the present invention is implemented in a gas hot water heater. In this figure, circulating water is sent by a pump 1 through a heat exchanger 2, an outgoing pipe 3 to a heating radiator 4 or a bathtub water heater 5, and returns to the pump 1 through a return pipe 6. A temperature sensor 7 is provided slightly upstream of the hot water passage outlet of the heat exchanger 2, and is adapted to detect the temperature of the hot water passing through it. In response to the temperature signal detected by the temperature sensor 7, the gas amount control device 8 continuously controls the amount of gas burned in the burner 9 so that the temperature of the hot water passing through the temperature sensor 7 reaches the set temperature. Here, the temperature sensor 7 is installed upstream from the outlet of the heat exchanger 2, and measures the hot water temperature of the return pipe 6 section at t ₁ °C, the hot water temperature of the outbound pipe 3 section at t ₂ °C, and the temperature sensor 7 section. If the temperature of the hot water is T°C, then when burning with a certain amount of gas, the temperature that rises as the hot water is heated while passing through the heat exchanger 2 can be considered to be approximately proportional to the distance traveled. , in the example of FIG. 1, t ₂ −t ₁ /T−t ₁ ≈1.2. In other words, if the hot water temperature T of temperature sensor 7 is
Considering the case of controlling the temperature to 70℃, from t ₂ −t ₁ /70−t ₁ ≒1.2, t ₂ +0.2t ₁ = 84, and the hot water temperature in the 6th part of the return pipe is 40℃ and 50℃. ℃、Heat exchanger 2 for 60℃
The hot water temperature at the outlet is as follows.

[Table] Since the heat load is (hot water temperature at the outlet of the heat exchanger - hot water temperature at the return pipe) x amount of circulating hot water, the above table shows that when the heat load is small, the heating efficiency is lower than when the heat load is large. The temperature of the hot water sent to the radiator 4 etc. becomes lower. In this way, according to this embodiment, the temperature sensor 7
By providing it slightly upstream of the outlet of the hot water passage of the heat exchanger 2, it is possible to easily obtain hot water at a high temperature when the heat load is large and hot water at a low temperature when the heat load is small. Effects of the Invention As described above, according to the present invention, the following effects can be obtained. (1) When the heat load is large, high-temperature hot water is circulated, so operation starts quickly. (2) When the heat load decreases, the hot water temperature gradually decreases, heat loss from circulation piping decreases, heat absorption in the heat exchanger improves, and operational efficiency improves. (3) To control the temperature of hot water sent from the heat source equipment,
Unlike the prior art, there is no need for a signal of the rotation speed of the fan of the radiator, which not only simplifies the installation work but also simplifies the configuration.

[Brief explanation of drawings]

The figure is a configuration diagram showing an embodiment of the present invention. 1... Pump, 2... Heat exchanger, 3... Outgoing pipe, 4... Heating radiator, 5... Bathtub water heater, 6
... Return pipe, 7 ... Temperature sensor, 8 ... Gas amount control device, 9 ... Burner, 10 ... Circulation piping, 11 ... Gas inlet, 12 ... Make-up water tank.

Claims (1)

[Claims] 1 A heat exchanger, a temperature sensor that detects the temperature of hot water passing through the heat exchanger, and a signal from this temperature sensor that controls the amount of fuel supplied to the heat exchanger heating source so that the hot water temperature remains constant. The hot water heater is equipped with a fuel control device that controls the temperature by continuously increasing and decreasing the temperature, and the temperature sensor is installed upstream of the outlet of the hot water heating path of the heat exchanger.