JPS6027864Y2 - hot water heater - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a hot water heater equipped with a dry-fire detector.

In general, in a hot water heater in which the can body of a hot water boiler and the radiator tube of a radiator are connected by piping to form a closed hot water circuit, and a sealed expansion tank is connected to this closed circuit, the can An empty-fire detector is installed in the can body, so if the upper part of the can becomes empty than the empty-fire detector, this empty-fire detector will not operate and the hot water boiler will continue to operate the burner. , dry firing will be carried out, albeit only in the upper part of the hot water boiler.

Furthermore, after using this type of heater for a long period of time, water may leak from valves, joints, etc. in the closed circuit.

In such a case, the pressure in the sealed circuit decreases, the water level in the sealed expansion tank decreases, a negative pressure is created in the piping and heat radiation pipes in the upper part of the can, and air enters the sealed circuit.
This is what is called air entrapment in the closed circuit, and when air enters the closed circuit in this way, the air accumulates in the upper part of the can body, causing dry firing in the upper part of the hot water boiler as described above. It is.

In addition, the above-mentioned dry firing detector has a problem in that the protruding structure of the detection rods becomes complicated because multiple detection rods for detecting the water level are installed in the water at different height positions of the detection parts. In addition, there was a problem in that the ten-electrode detection rod would elute water when energized, shortening the life of the detection rod.

Therefore, the present invention was devised to solve the above-mentioned problems, and its purpose is to reduce the number of detection rods for detecting the water level of the dry-fired detector to one, and also to reduce the number of detection rods to ten poles. It can prevent the electrode material from leaching into the water and extend its life.
Moreover, there is no risk that the hot water boiler will run dry under any circumstances, and there is no air in the hot water sealed circuit formed by connecting the hot water boiler body and the radiator tube of the radiator with piping. To provide a hot water heater capable of detecting the intrusion of air into a so-called closed circuit without using a special detection device.

That is, the present invention provides an empty firing detector connected to a hot water sealed circuit and using a detection rod as a ferrite acid on the side wall of the sealed expansion tank. The water in the expansion tank is energized using the detection rod as a conductor, and when the water level in the expansion tank becomes lower than the water level of the dry firing detector, the energization of the water is cut off. The present invention is characterized in that it is configured to detect this and stop the burner operation of the boiler.

Embodiments of the present invention will be described below based on illustrative drawings.

In the figure, 1 is a hot water boiler equipped with a burner 2, and a can body 3 of the boiler 1 and a heat radiation pipe 5 of a radiator 4 are connected by a feed pipe 7 and a return pipe 8 to form a closed circuit 6 for hot water. A water supply pipe 9 in which a pump P is interposed in the middle of the feed pipe 7 in the circuit 6, and a pressure reducing check valve 10 and a stop pulp 11 are provided in the can body 3 of the hot water boiler 1.
Connect.

On the other hand, a sealed expansion tank 12 is connected to the feed pipe 7 in the hot water sealed circuit 6 via a branch pipe 13, and an empty firing detector 14 is provided in the tank 12, so that the water level in the sealed expansion tank 12 is set. When the water level drops below the water level, the operation of the burner 2 and pump P is stopped.

The sealed expansion tank 12 may be connected to the return pipe 8 or the can body 3 in the sealed circuit 6.

The sealed expansion tank 12 is hollow inside, and the pressure of the hot water sealed circuit 6 is maintained within a predetermined range by the pressure and expansion of the internal air layer.

The dry firing detector 14 is constructed by inserting a ferrite detection rod 16 into the inner cavity of the plug 15 as shown in FIG.
The inner cavity of the plug 15 is filled with epoxy resin 17, and a ring 18 made of phoristerite is attached to the detection rod 16.
The inner cavity of the plug 15 is closed by the ring 18, and the lead wire 19 is extended from the detection rod 16, and is formed on the side wall of the sealed expansion tank 12. By inserting and fixing the plug 15 into the through hole, using the side wall of the sealed expansion tank 12 as one pole, using the detection rod 16 as a child, and energizing the water in the tank 12 as a moving body, the burner 2 and an operation control circuit for the pump P.

The hot water heater of the present invention is constructed as described above, and hot water is supplied from a water pipe (not shown) into a sealed circuit 6 and a sealed expansion tank 12 via a water supply pipe 9 equipped with a pressure reducing check valve 10 and a stop pulp 11. When the water is supplied and the pressure in the sealed circuit 6 reaches, for example, 0.6 atg (gauge pressure), the stop pulp 11 is closed to stop the water supply, and in this state the burner 2 is operated to close the can. At the same time as heating the ice inside the can body 3, the pump P sends the hot water inside the can body 3 via the feed pipe 7 to the heat radiation pipe 5 of the radiator 4 for heating. The heat-exchanged water is returned to the can body 3 via the return pipe 8.

When water leaks from the hot water sealed circuit 6 and the pressure in the sealed circuit 6 decreases, the water level in the sealed expansion tank 12 drops, and the water level is lower than the setting, that is, lower than the empty firing detector 14. If so, the detection rod 1 in this dry firing detector 14
6 to the side wall of the sealed expansion tank 12 is cut off, and the operation of the burner 2 and pump P is stopped.

Therefore, if the pressure in the hot water sealed circuit 6 falls below a predetermined value, the operation of the burner 2 and pump 6 will not be restarted unless water is supplied to the sealed circuit 6, so that the so-called sealed circuit 6
The dry heating detector 14 detects the air trapped inside, and there is no possibility of heating operation in a state where the air is trapped.

Moreover, the dry firing detector 14 has one detection rod 16, and the detection rod 16 is made of ferrite acid with high resistivity.
Since there is no need for a series resistor to suppress the current flowing, the structure is simple. Also, since the ferrite acid detection rod 16 is used as a terminal and the side wall of the tank is used as one pole, the electrode material does not elute into the water from both electrodes. can be prevented.

As explained above, the hot water heater according to the present invention has a sealed expansion tank 2 connected to a closed circulating circuit 6 for hot water formed by connecting the can 3 of the boiler 1 and the radiating pipe 5 of the radiator 4 through piping 7 and 8. By connecting this circuit, the circuit becomes a completely sealed circuit, and the expansion tank 12 does not need to be installed on the roof unlike an open circuit using an open expansion tank, and can be installed anywhere.It also needs to have a waterproof and heat-proof structure. It is extremely easy to install, especially in the case of high-rise buildings, because it can be installed with other machines in machine rooms such as basements, and can be packaged with the boiler itself.Furthermore, it does not use a ball tap like an open type, so there is no risk of failure. There is no problem and the operation is reliable.

The empty firing detector uses the side wall of the expansion tank as one of the + and - electrodes, and the detection rod is used only for the seeds, so only one detection rod can be used. ,
Since it is made of ferrite, which has an extremely large resistivity of about 103 Ωcm or more, there is no need to connect a series resistor to suppress the current flowing, and the dry-burning detector can be made extremely simple.

Moreover, since the side wall of the expansion tank is single-pole, the side wall material will not elute into the water when energized.Also, although the detection rod is a child, it is made of ferrite, so it will not elute into the water even when energized continuously. There is little to do, and there is no need to worry about shortening the life of the detection rod.

Furthermore, since the dry-fire detector is installed in the sealed expansion tank, the dry-fire detector does not operate until the top of the hot water boiler's can is empty, as in the past, but when the dry-fire detector is activated when the top of the hot water boiler's can is empty. Before the hot water boiler becomes empty, the empty firing detector is activated and the burner operation of the hot water boiler is stopped.

Therefore, dry firing of this hot water boiler can be prevented extremely reliably.

In other words, if the pressure in the closed circuit of hot water decreases, the water level in the closed expansion tank will drop, and the dry-fire detector will operate, stopping the burner operation. Since the dry firing detector will not restart unless the pressure in the sealed circuit is raised to a predetermined value or higher, that is, the water level in the sealed expansion tank is raised, the dry firing detector performs so-called air trapping detection, and detects air trapping. There is no fear that heating operation will occur.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic explanatory diagram thereof, and FIG. 2 is a sectional view of the main part thereof. 1...Hot water boiler, 2...Burner 3...Can body, 4...Radiator, 5...
...Radiation tube, 6...Hot water sealed circuit, 7.
...Feed piping, 8...Return piping, 12.
... Sealed expansion tank, 14 ... Empty firing detector.

Claims (1)

[Scope of utility model registration request] A hot water boiler 1 and a radiator 4 are provided, and the can body 3 of the boiler 1 and the radiator tube 5 of the radiator 4 are connected by piping 7.8 to form a closed circulation circuit 6 for hot water. 6 and a sealed expansion tank 12, a detection rod 16 is attached to the side wall of the expansion tank 12.
An empty firing detector 14 made of ferrite is provided, and the empty firing detector 14 has one pole on the side wall of the sealed expansion tank 12, ten poles on the detection rod 16, and uses the water in the expansion tank 12 as a moving object. When the water level in the expansion tank 12 becomes equal to or lower than the water level of the dry firing detector 14, it is detected that the water supply is cut off and the burner operation of the boiler 1 is stopped. A hot water heater that features the following features: