JPH0849865A - Indoor unit for hot water heater - Google Patents

Abstract

PURPOSE:To prevent the reverse feed of hot water in a heat exchanger by detecting the tube connection miss between an outdoor unit and the exchanger from the temperature of the inlet side of the exchanger provided in the indoor unit of a hot water heater and switching a water channel switching means provided between the forward tube and the return tube of the hot water when there is the tube connection miss. CONSTITUTION:A hot water heater has an indoor unit 1 having a heat exchanger 6 in which hot water is used as a heat source, and a blower 7 for feeding warm air into a room, an outdoor unit 2 for producing the hot water, and a forward tube 19 and a return tube 20 of the hot water connected between the unit 2 and the exchanger 6. Water channel switching means 11 for switching the flow of the hot water is provided at the tubes 19, 20, and a temperature sensor 9 for detecting the hot water temperature is provided at the inlet side of the exchanger 6. When the hot water temperature of the inlet side of the exchanger 6 is a specific value or less, it is decided that the connection of the tubes 19 and 10 is reverse, and the means 11 is controlled to be switched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the construction and operation control of an indoor unit of a hot water heater called a fan convector.

[0002]

2. Description of the Related Art A hot water heater includes, for example, an indoor unit 31 called a fan convector as shown in FIG. 6 and an outdoor unit 32 called an oil-fired hot water boiler and used as a heat source unit of the indoor unit 31. There is something. The indoor unit 31 has its housing
The indoor air suction port 34 is located in the upper rear part of the 33, the hot air outlet 35 to the room is located in the lower front part, the heat exchanger 36 using the hot water from the outdoor unit 32 as a heat source, and this heat The blower 37 that sends the air warmed by the exchanger 36 to the room, and the blower 37
There is a control unit 38 for controlling the temperature of the housing 33, and a temperature sensor 39 for detecting the temperature of the hot water returning from the heat exchanger 36 to the outdoor unit 32. A temperature sensor 41 for detecting the room temperature is provided. A boiler 42 that generates hot water, a cis tank 43 that stores hot water, and a pump 44 that circulates the hot water to the indoor unit 31 are provided on the outdoor unit 32 side.
And an outdoor unit controller that controls the boiler 42, the pump 44, and the like.
There is a 45, and the outdoor unit control unit 45 and the control unit 38 on the indoor unit 31 side
Is connected by a signal line 46, and the outdoor unit 32 and the indoor unit 31 are connected by a hot water outflow pipe 47 and a return pipe 48. The outgoing pipe 47 and the return pipe 48 are relayed by hot water outlets 50 provided on a wall surface 49 on the indoor side.

[0003]

The forward pipe 47 and the return pipe 48 having the same diameter are used in FIG.
The normal piping work as shown in (A) is not always performed, and the connections as shown in (B), (C), and (D) may be performed. (B) is an outdoor unit 32 and a hot water outlet
50 and the hot water outlet 50 and the heat exchanger 36 are reversely connected, respectively, and as a result, there is no problem in the traveling direction of the hot water, but the reverse connection as shown in (C) and (D) is performed. If this happens, the traveling direction of the hot water circulated in the heat exchanger 36 will be reversed, and the operation control will be hindered. Therefore, in order to eliminate such pipe connection mistakes, conventionally, markings that serve as marks on the pipes (the forward pipe 47 and the return pipe 48), the pipe insulation materials are color-coded, and the pipes are traced by hand, The method of manually confirming the pipe temperature in the trial operation after connecting the pipes was used, but it was not only time-consuming, but there were problems such as lack of accuracy. Therefore,
It is an object of the present invention to provide an indoor unit of a hot water heater that can easily perform the above-mentioned piping work and can operate normally even if there is a mistake in the piping connection.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is directed to a housing having a room air suction port in the upper rear portion and a warm air outlet in the lower front portion. A heat exchanger that uses hot water as a heat source to circulate from an outdoor unit inside, a blower that sends out the air warmed by the heat exchanger into the room, a control unit that controls the blower, and the like. A water passage switching means for switching the flow of hot water to the heat exchanger is provided between a hot water outgoing pipe and a return pipe that connect the outdoor unit and the heat exchanger, and the hot water is supplied to the hot water pipe on the inlet side of the heat exchanger. A temperature detecting means is provided, and it is determined from the hot water temperature detected by the detecting means whether or not the traveling direction of the hot water is normal. If not, the water channel switching means is switched.

[0005]

The temperature of the hot water sent from the outdoor unit to the heat exchanger is controlled, for example, at 80 ° C. Therefore, the temperature at the inlet side of the heat exchanger will be the same as long as there is no pipe connection error between the outdoor unit and the heat exchanger. The temperature of the hot water that returns to the outdoor unit from the heat exchanger becomes approximately 80 ° C, and the temperature of the hot water that returns to the outdoor unit becomes approximately 60 ° C. However, with the above configuration, the temperature of the hot water at the inlet side of the heat exchanger can be detected. From the detected value, it can be determined whether the direction of warm water is normal or not, and if it is not normal, the direction of hot water can be changed by switching the water channel switching means provided between the hot water forward pipe and the return pipe. Therefore, even if there is a pipe connection error, hot water can be normally circulated in the heat exchanger.

[0006]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 shows a schematic configuration of a hot water heater. 1 is an indoor unit called a fan convector, 2 is an oil-fired hot water boiler, and an outdoor unit used as a heat source unit of the indoor unit 1. The indoor unit 1 has an inlet 4 for indoor air in the upper rear part of the housing 3, an outlet 5 for warm air into the room in the lower front part, and uses hot water from the outdoor unit 2 as a heat source inside. There is a heat exchanger 6, a blower 7 that sends out the air warmed by the heat exchanger 6 to the room, and an indoor unit controller 8 that controls the blower 7 and the like, and piping on the inlet side of the heat exchanger 6 is provided. When the temperature sensor 9 is attached to the (outgoing pipe) and the temperature sensor 10 is attached to the outlet side pipe (return pipe), when there is a pipe connection error between the outgoing pipe and the return pipe in the housing 3. Water channel switching means 11 capable of switching the flow of hot water to the heat exchanger 6 is provided. Further, a driving operation unit 12 is provided on the upper front portion of the housing 5, and a temperature sensor 13 for detecting the indoor temperature is provided on the lower rear portion. In one of the outdoor units 2, a boiler 14 that generates hot water, a cis tank 15 that stores hot water, a pump 16 that circulates the hot water to the heat exchanger 6, an outdoor unit control unit 17 that controls the boiler 14, the pump 16, and the like. Is provided, and the outdoor unit control unit 17 and the control unit 8 on the indoor unit 1 side are connected by a signal line 18. The hot water outflow pipe 19 and the return pipe 20 connecting the outdoor unit 2 and the indoor unit 1 are relayed by a hot water outlet 22 attached to a wall surface 21 of the building.

FIG. 2 shows a concrete example of the water channel switching means 11. The water channel switching means 11 is provided with a first opening / closing valve 23 provided in the hot water outflow pipe 19 and a first on-off valve 20 provided in the return pipe 20. The second opening / closing valve 24 and the third opening / closing valve 25 provided in an intersecting manner between the inlet sides and the outlet sides of these two opening / closing valves 23, 24.
And a fourth on-off valve 26, which is normally on-off valve 23,
24 is open and the on-off valves 25 and 26 are closed. Then, as shown in FIG. 2A, if there is no pipe connection error in the forward pipe 19 and the return pipe 20 between the outdoor unit 2 and the heat exchanger 6, the temperature sensor 9 detects the inlet side of the heat exchanger 6. The hot water temperature is about 80 ° C., the hot water temperature on the outlet side of the heat exchanger 6 detected by the temperature sensor 10 is about 60 ° C., and the opening / closing valve 23,
24, 25 and 26 are held in the state they were in when the operation started. If the forward pipe 19 and the return pipe 20 are reversely connected as shown in FIG. 2 (B), the flow of hot water in the heat exchanger 6 is reversed, and the original temperature detected by the temperature sensor 9 is detected. The temperature on the inlet side becomes lower than the temperature on the outlet side. Therefore, the control unit 8 determines the pipe connection error by comparing the temperature on the inlet side with a preset reference value (for example, 78 ° C.). If there is a pipe connection error, the opening / closing valve 25 , 26 are opened and the on-off valves 23, 24 are closed. FIG.
Shows the outline of the control system.

By the way, the pipe connection error may be judged by the temperature on the inlet side of the heat exchanger 6 as described above, but as another method, the temperature on the outlet side of the heat exchanger 6 is a predetermined value or more ( For example, when the temperature is 78 ° C. or higher), or the temperature difference between the inlet side and the outlet side of the heat exchanger 6 may be used for the determination. FIG. 4 is a flowchart showing the latter case. When an operation start instruction signal is input to the indoor unit control section 8, the temperature at the inlet side of the heat exchanger 6 is detected in step ST1, and in step ST2. Detects the temperature on the outlet side, step ST
In 3, the inlet temperature and the outlet temperature are compared. If the inlet temperature is higher than the outlet temperature, it is assumed that there is no pipe connection error, and the waterway switching means 11 proceeds to step ST5 while maintaining the current state. If it is smaller than this, it is assumed that there is a pipe connection error, the process proceeds to step ST4, and after switching the water channel switching means 11, the process proceeds to step ST5. At step ST5, the outlet temperature is equal to or higher than a predetermined value (for example, 55 ° C.). After waiting for the above (), the process proceeds to step ST6 to start the operation of the blower 7.

The water channel switching means 11 is not limited to the one using the on-off valves 23, 24, 25, 26 as shown in FIG. 2, but as shown in FIG. Valve 27
The return pipe 20 is provided with a second three-way valve 28, and
The switching port c of the three-way valve 27 of the second three-way valve 28 to the outlet side b (or the inlet side a) of the second three-way valve 28, the first switching port c of the second three-way valve 28.
The three-way valve 27 may be connected to the inlet side a (or the outlet side b) in an intersecting manner. If there is a pipe connection error between the outdoor unit 2 and the heat exchanger 6, the first and second The water passages of the on-off valves 27 and 28 may be controlled to be switched to the switching port side.

[0010]

As described above, in the case of the hot water heater as described above, even if there is a pipe connection error between the outdoor unit and the heat exchanger on the indoor unit side, the warm air heating operation is not started. Since the flow of hot water can be switched to the normal state, it is safe and convenient for piping work and trial run.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a hot water heater showing an embodiment of the present invention.

FIG. 2 is a hot water circuit diagram including the water channel switching means of the present invention.

FIG. 3 is a control block diagram of the hot water heater according to the present invention.

FIG. 4 is a flowchart showing another control operation example of the present invention.

FIG. 5 is a hot water circuit diagram including another water channel switching means of the present invention.

FIG. 6 is a schematic configuration diagram of a conventional hot water heater.

FIG. 7 is a hot water circuit diagram showing a specific example of a pipe connection error.

[Explanation of symbols]

 1 Indoor unit (fan convector) 2 Outdoor unit (oil-fired hot water boiler) 3 Case 6 Heat exchanger 7 Blower 8 Control unit (indoor unit control unit) 9 Temperature sensor 10 Temperature sensor 11 Water channel switching means 19 Hot water outflow pipe 20 Hot water return pipe 22 Hot water outlet

Claims (7)

[Claims] 1. A heat exchanger using hot water as a heat source, which circulates from an outdoor unit inside a casing having a suction port for indoor air at an upper rear portion and a blowout port for warm air at a lower front portion, and the heat exchanger. In a blower for sending out the air warmed by a room to the room, a control unit for controlling the blower, etc., the hot water forward pipe and the return pipe connecting the outdoor unit and the heat exchanger, Water channel switching means for switching the flow of hot water to the heat exchanger is provided, and hot water temperature detecting means is provided in the hot water pipe on the inlet side of the heat exchanger, and the direction of travel of hot water from the hot water temperature detected by the detecting means. Is determined to be normal, and if not normal, the water channel switching means is controlled so as to be switched, and the indoor unit of the hot water heater. 2. A heat exchanger using hot water as a heat source, which circulates from an outdoor unit inside a housing having an inlet for indoor air in the upper rear part and an outlet for warm air in the lower front part, and the heat exchanger. In a blower for sending out the air warmed by a room to the room, a control unit for controlling the blower, etc., the hot water forward pipe and the return pipe connecting the outdoor unit and the heat exchanger, Water channel switching means for switching the flow of hot water to the heat exchanger is provided, and hot water temperature detecting means is provided at the hot water pipes on the inlet side and the outlet side of the heat exchanger, and the difference between the hot water temperatures detected by both detecting means is provided. The indoor unit of the hot water heater is characterized in that whether or not the traveling direction of the hot water is normal is determined, and if it is not normal, the water channel switching means is controlled to be switched. 3. A first and a second on-off valve, wherein the water channel switching means is provided on an outflow pipe and a return pipe to the heat exchanger, and between the inlet sides and between the outlet sides of these two on-off valves. A third and a fourth on-off valve which are provided in a cross shape with each other, and when the traveling direction of the hot water to the heat exchanger is not normal, the first and the second on-off valves are closed, and the third and the fourth on-off valves are closed.
3. The on / off valve of the control unit is controlled so as to be opened.
Indoor unit of the hot water heater described. 4. The first and second three-way valves are provided on the outflow pipe and the return pipe to the heat exchanger as the water channel switching means, and the switching port of the first three-way valve is the inlet of the second three-way valve. Side or outlet side, the switching port of the second three-way valve is connected to the outlet side or the inlet side of the first three-way valve in an intersecting manner, and if the traveling direction of the hot water to the heat exchanger is not normal, The indoor unit of the hot water heater according to claim 1, wherein the water passages of the first and second opening / closing valves are controlled so as to be switched to the switching port side. 5. The method according to claim 2, wherein whether or not the temperature of the inlet side of the heat exchanger is higher than the temperature of the outlet side of the heat exchanger determines whether or not the traveling direction of the hot water to the heat exchanger is normal. Indoor unit of hot water heater. 6. The indoor unit for a hot water heater according to claim 1, wherein the water channel switching means is controlled to switch when the temperature on the inlet side of the heat exchanger is equal to or lower than a predetermined value. 7. The indoor unit of the hot water heater according to claim 2, wherein the water channel switching means is controlled to switch when the temperature on the outlet side of the heat exchanger is equal to or higher than a predetermined value.