JPH0212530Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a freezing prevention device for a stop-start type water heater.

For water heaters used in cold regions,
When the temperature of the atmosphere drops to a temperature that freezes the water accumulated inside the vessel consisting of the water flow reactor, heat exchanger, piping, etc. when hot water is stopped, the system detects the atmospheric temperature or water temperature and activates the anti-freeze valve. A simple, so-called flowing water type antifreeze device that automatically discharges a predetermined amount of tap water, etc. into the opener body to prevent freezing due to a drop in temperature inside the opener body, eliminating the need to incorporate an electric heater into the opener body. Some anti-freezing devices have already been proposed, but these water-flow type antifreeze devices detect water temperature or atmospheric temperature on the hot water outlet side, for example, as seen in Japanese Patent Application Laid-Open No. 55-31216. Either the anti-freeze valve installed on the hot water outlet side is opened and water is discharged, or only the faucet is closed after use, and when the water supply tap is closed, the water pressure detection type drain valve installed on the water supply side is also opened due to a drop in internal pressure and the hot water is discharged. There are structures that quickly remove accumulated water from both the water supply side and prevent freezing, but in this case, the antifreeze valve opens and closes by detecting the water temperature on the hot water outlet side or the atmospheric temperature. After the hot water supply is stopped, the temperature of the water remaining in the vessel remains high for a considerable period of time, so it takes a considerable amount of time for the water to cool down to near freezing temperature (for example, below 1 to 2 degrees Celsius) and for the antifreeze valve to operate. However, there is a serious drawback in that the accumulated water on the water supply side, where the water temperature is low, reaches freezing temperature during that time. In addition, the stop-start type water heater disclosed in Japanese Patent Publication No. 52-22695 has water drain passages before and after the hydraulic reactor, and when the detected water freezes, both water drain passages are opened by an antifreeze valve to drain the accumulated water. Or, only the drain passage on the downstream side is opened to allow tap water, etc. to flow out. In this case, the temperature sensing part of the anti-freeze drain valve is exposed to the atmosphere at a position that protrudes from the water supply channel. Since the temperature of the supplied water cannot be detected accurately, the antifreeze valve starts operating quickly, and the heat conduction of the discharged water to the detected water is small even though the detected water is thawed due to the excess temperature of the discharged water. It takes a considerable amount of time to do this, and more runoff water is released than necessary, which is extremely uneconomical.
Particularly in severe cold weather, a considerable amount of water is wasted, which poses a practical problem.

This invention was made in view of the problems of the conventional technology, and its purpose is to accurately detect the temperature of the accumulated water on the water supply side in a flowing water type antifreeze device to prevent freezing. A stop-start type water heater that allows quick and reliable freezing prevention to be carried out economically by creating a running water path that allows the minimum flow rate of water required for the hot water to flow through the hot water outlet side and drains from the water supply side. The purpose is to provide an antifreeze device.

In order to achieve the above object, the anti-freezing device for a water heater according to this invention includes a water flow reactor that opens and closes a gas passage in response to water flow, and a fuel gas supplied through the water flow reactor. A stop-start type water boiler consisting of a gas burner that burns with a gas burner, a heat exchanger that heats water supply with the combustion flame of the gas burner, and a hot water tap that releases or stops the hot water that has been heated and heated by the heat exchanger. In the water flow reactor, a temperature-measuring liquid is buried in flowing water in the water supply channel upstream of the water flow response device, and when the water temperature in the water supply channel decreases and approaches freezing temperature, the temperature-measuring liquid heat-sensitively shrinks and the temperature-measuring liquid is buried upstream of the hot water tap. The structure includes a tip valve part that opens a water drain conduit branching from the side to a drainage channel on the water supply side, and an antifreeze valve that allows the minimum flow rate necessary for freezing prevention to flow through the hot water outlet side.

Since this device has the above-mentioned structure, when the water accumulated in the water heater's water flow reactor, heat exchanger, piping, etc. approaches freezing temperature, the temperature measuring liquid of the antifreeze valve detects this. The heat-sensitive contraction causes the tip valve to be lifted and separated from the valve seat, opening the water drain conduit to the drainage channel, so water at the flow rate required to prevent freezing flows through the outlet channel to the water supply side, preventing freezing inside the vessel. prevent.

However, the temperature of the running water reaches a temperature higher than that required for freezing depending on the temperature of the tap water, so the temperature measuring liquid detects this and expands thermally, pushing down the valve tip and pressing it against the valve seat to drain the water. The flow of running water will be stopped as the headrace channel and drainage channel will be closed. When the accumulated water in the water supply reaches the freezing temperature again, the tip of the antifreeze valve separates from its valve seat, opens the water drain conduit to the drainage channel, and repeats the flow of water, preventing freezing. The required minimum flow rate is obtained.

An embodiment of this invention will be described below with reference to the drawings.

Figure 1 is a schematic diagram of the entire structure of the stop-start water heater according to this invention, which includes a water flow reactor B that opens and closes the gas passage in response to water flow, and a fuel gas supplied through the water flow reactor B. Gas burner E burns by
, a heat exchanger C that heats the water supply with the combustion flame of the gas burner E, and a hot water tap D that discharges or stops the hot water heated and heated by the heat exchanger C, and the water flow reactor B An antifreeze valve A, which will be described later, is provided in the water supply channel 1 on the upstream side. FIG. 2 is a detailed sectional view of the antifreeze valve A, which is located upstream of the water flow reactor B of the water supply channel 1 and most susceptible to the influence of outside temperature (for example, the water supply channel 1). A temperature measuring body 4 containing a bellows 3 filled with a temperature measuring liquid 2 that expands and contracts when detecting the temperature of the water accumulated inside the vessel is inserted into the water supply channel 1, and is installed near the corner of 1. The base end of the valve stem 5 is connected to the movable tip of the bellows 3, and the tip valve portion 6 of the valve stem 5 is connected to the movable tip of the bellows 3.
are arranged so as to approach and separate from a valve seat 8 provided at the open end of the drainage channel 7, and the valve stem 5 is moved by a spring 9 in a direction in which the tip valve portion 6 is separated from the valve seat 8 and is always open. The structure is biased, and the minimum flow rate required for freezing prevention is determined by the opening area of the drainage channel 7. Reference numeral 10 denotes a hot water outlet, and 11 a drain conduit that branches from the upstream side of the outlet tap D of the hot water outlet 10 and connects with the drain 7. The drain conduit 11 and the drain 7 are connected to the valve section. 6 comes into contact with and separates from the valve seat 8, thereby communicating and cutting off the valve.
The mounting structure of the thermometer 4 is such that an engagement flange 13 of the thermometer 4 is attached to an engagement step 12 provided in the water supply channel 1.
and tighten the ends of the buffer spring 1 with the screw plate 14.
It is pressed and supported via 7. Then, a plurality of water passage holes 15 and 16 are bored in the periphery of the engagement step portion 12 and the engagement flange 13, respectively, and the tightening screw plate 1
A large number of water passage holes 18 are also bored in the peripheral edge of the thermometer 4 so that the accumulated water always surrounds the thermometer 4, and the water flowing during freezing prevention flows to surround the thermometer 4, so that the temperature measurement liquid 2 This ensures that the water temperature can be detected reliably.

In the above configuration, the temperature of the atmosphere decreases and the water staying in the water heater's water flow reactor B, heat exchanger C, piping, etc. reaches a predetermined temperature (1 to 1) close to the freezing value.
2°C), the temperature measuring liquid 2 of the temperature detecting body 4 installed in the water supply channel 1 on the upstream side of the water flow reactor B detects this and the temperature measuring liquid 2 contracts, so that the valve stem 5 becomes spring 9. The elastic force causes the bellows 3 to contract and move upward, thereby separating the valve tip 6 from the valve seat 8 and opening the drainage conduit 11 to the drain 7. Therefore,
From the upstream side of the water supply channel 1, antifreeze valve A → water flow reactor B → heat exchanger C → outlet channel 10 → water drain conduit 11
→The minimum flow rate of tap water, etc. necessary for preventing freezing flows along the route of the drainage channel 7, thereby preventing freezing inside the vessel. The minimum temperature of tap water that flows through the container during freezing prevention is usually 5 to 6 degrees Celsius in winter, so when the water reaches this temperature, the temperature measuring liquid 2 detects this and the temperature measuring liquid 2 It expands and presses the valve stem 5 downward against the spring 9 through the bellows 3 to press its tip valve portion 6 against the valve seat 8 and drain water conduit 1.
1 and drainage channel 7 are closed to stop the flow of water. Thus, after stopping, the temperature of the water remaining in the container body will be 1 to 2 degrees Celsius.
When the temperature reaches near the freezing point, the same operation is repeated again to keep the inside of the vessel always between 1 and 6 degrees Celsius.

In the above embodiment, the temperature measuring liquid 2 is completely absorbed by flowing water through the plurality of water passage holes 18 and the water passage recesses 15 and 16 bored in the periphery of the tightening screw plate 14, the engaging step portion 12, and the engaging flange 13. Because it is surrounded by
The freezing temperature of accumulated water and the temperature of running water such as tap water can be detected sensitively and accurately. If the thermometer 4 is installed at an appropriate location in the water supply channel 1 where the influence of outside air temperature is greatest, such as a corner near the outer casing of the container, the water temperature at the lowest temperature part of the container can be detected. Therefore, there is no possibility that an error will occur in the operating temperature of the antifreeze valve A.

As explained above, this invention detects the freezing temperature in a stop-start water heater by bringing a thermometer built into the upstream side of the water supply into direct contact with the standing water and running water, and When a freezing temperature is detected, the water drain conduit that branches from the upstream side of the hot water tap is opened to the water supply side drainage channel, allowing the minimum flow rate necessary to prevent freezing to flow through the hot water tap side. , when the accumulated water in the vessel reaches near the freezing value,
The anti-freeze valve operates immediately to open the water drain conduit to the drainage channel and allow tap water, etc. to flow through the container body, so freezing inside the container is prevented and the temperature of the running water, such as tap water, is reduced to freezing. When the temperature exceeds the limit, the anti-freeze valve operates, closing the water drainage conduit and drainage channel and stopping the flow of tap water, etc., so that the water discharge becomes the minimum flow rate required to prevent freezing. This has the effect of economically preventing freezing.

[Brief explanation of the drawing]

FIG. 1 is an overall schematic diagram showing an embodiment of this invention, and FIG. 2 is a sectional view of the antifreeze valve. A... Antifreeze valve, B... Water flow reactor, C...
Heat exchanger, D... hot water tap, E... gas burner, 1
... Water supply channel, 2 ... Temperature measurement liquid, 7 ... Drainage channel, 1
1... Water drain conduit.

Claims (1)

[Scope of utility model registration request] A water flow reactor B that opens and closes the gas passage in response to the water flow, a gas burner E that burns with the fuel gas supplied via the water flow reactor B, and heat that heats the water supply with the combustion flame of the gas burner E. In a stop-start type water heater consisting of an exchanger C and a tap D for dispensing or stopping the dispensing of hot water heated and heated by the heat exchanger C, in the water supply conduit 1 on the upstream side of the water flow reactor B. To,
The temperature measuring liquid 2 is buried in running water, and when the water temperature in the water supply channel 1 decreases and approaches freezing temperature, the temperature measuring liquid 2 contracts thermally and branches from the upstream side of the hot water tap D. This antifreeze device for a stop-start water heater is provided with an antifreeze valve A that has a tip valve part 6 that opens a drainage channel 7 of the water heater and allows the minimum flow rate necessary for freezing prevention to flow through the outlet side.