JP2003106547A - Bathroom heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bathroom heating device preventing troubles that may occur when it is operated for heating as a fan is rotated for a predetermined time at an rpm that is lower than a lower limit rpm at which a sufficient amount of air is produced to detect temperature within a bathroom. SOLUTION: If either of three conditions, resetting for elevating temperature, resetting for increasing the amount of air, and the temperature detected by a room temperature thermistor 29 being at a desired temperature (Ta) of -3 deg.C or less, is met during the execution of a 'heating zero cycle' in which the rpm of a circulating fan 24 is at three speeds set lower than a lower limit rpm at which a sufficient amount of air is produced to detect temperature in a bathroom by the room temperature thermistor 29 provided in an inflow passage of air sucked through an air inlet 23, a controller 20 keeps the rpm of the circulating fan 24 at or above the lower limit rpm, and temperature inside the bathroom is quickly elevated until the temperature detected by the bathroom thermistor 29 reaches the desired temperature (Ta).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bathroom heating device for heating a bathroom by using hot water as a heat source.

[0002]

2. Description of the Related Art Conventionally, a hot water type heat exchanger to which hot water of a predetermined temperature is supplied as a heat source is provided, and the air heated by the heat exchanger is blown into the bathroom as warm air to heat the bathroom. Bathroom heating systems that perform are known. In such a bathroom heating device, after the heating operation is started, temperature control is performed so that the temperature inside the bathroom is maintained at the target temperature set by the temperature setting switch or the like.

A bathroom temperature sensor for detecting the temperature in the bathroom is generally provided in a path through which the air in the bathroom is sucked by a circulation fan that circulates the air in the bathroom via the heat exchanger. However, in this case, in order to detect the temperature in the bathroom by the bathroom temperature sensor, the blower fan is rotated at a certain number of revolutions or more to circulate the air in the bathroom sufficiently and It is necessary to generate an air volume that can introduce air to the bathroom temperature sensor.

Therefore, when the heating operation is performed while detecting the temperature in the bathroom by the bathroom temperature sensor, during the heating operation, the rotation speed of the blower fan is such that the air in the bathroom is sufficiently circulated and the air in the bathroom is circulated. Is required to be kept above the lower limit rotation speed that produces the amount of air required to introduce into the bathroom temperature sensor.

However, when the bathroom is narrow relative to the heating capacity of the bathroom heating device or when the difference between the target temperature and the outside air temperature is small, even if the rotation speed of the blower fan is reduced to the lower limit rotation speed, The temperature may exceed the target temperature, and the temperature in the bathroom may not be maintained at the target temperature. Therefore, in such a case, it is possible to suppress the temperature rise in the bathroom by rotating the blower fan at a rotation speed lower than the lower limit rotation speed for a predetermined time.

However, when the blower fan is rotated at a rotation speed lower than the lower limit rotation speed for a predetermined time as described above, the inventors of the present invention accurately measure the temperature in the bathroom by the bathroom temperature sensor within the predetermined time. It has been found that various inconveniences may occur because it cannot be detected well.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and when the heating operation is performed, the rotation speed lower than the lower limit rotation speed that produces an air volume capable of detecting the temperature in the bathroom. It is an object of the present invention to provide a bathroom heating device in which the inconvenience that may occur when the temperature rise in the bathroom is suppressed by rotating the blower fan for a predetermined time.

[0008]

The present invention has been made in order to achieve the above object, and a heat exchanger using hot water supplied at a predetermined temperature as a heat source, and a heat exchanger that sucks air. A fan that blows air that has passed through the heat exchanger into the bathroom, a bathroom temperature sensor that is provided in an inflow path of air that is sucked by the fan, and hot water is supplied to the heat exchanger. In this state, by operating the fan, the air heated by passing through the heat exchanger is blown into the bathroom, and the fan is rotated so that the temperature detected by the bathroom temperature sensor matches a predetermined target temperature. A heating control means for executing a heating operation for controlling the number of heating fans, wherein the heating control means can detect the rotation speed of the fan by the bathroom temperature sensor to detect the temperature in the bathroom when the heating operation is executed. Wind If the detected temperature of the bathroom temperature sensor exceeds the target temperature even if the temperature is lowered to the lower limit rotation speed that causes the above, the bathroom heating device that operates the fan for a predetermined time at a low rotation speed set lower than the lower limit rotation speed Regarding the improvement of.

The first aspect of the present invention aims to eliminate the inconvenience that occurs when the target temperature setting means for setting the target temperature is provided. That is, when the target temperature is changed by the target temperature setting means within the predetermined time during which the fan is rotating at the low speed rotation speed set lower than the lower limit rotation speed, the predetermined time When the rotation speed of the fan is maintained at the low rotation speed until the time elapses, the amount of heat supplied from the bathroom heating device is maintained until the predetermined time elapses even though the target temperature is increased. Since it does not increase, there is a disadvantage that a time lag is caused before the temperature in the bathroom begins to rise, and the bather feels uncomfortable.

Therefore, the first aspect of the present invention comprises target temperature setting means for setting the target temperature, and the heating control means changes the target temperature by the target temperature setting means within the predetermined time. When the temperature detected by the bathroom temperature sensor becomes equal to or higher than the target temperature,
The fan is operated at a rotational speed equal to or higher than the lower limit rotational speed.

According to the present invention, when the target temperature setting means changes the target temperature to increase within the predetermined time, the heating control means causes the temperature detected by the bathroom temperature sensor to be equal to or higher than the target temperature. The fan is rotated at a rotational speed equal to or higher than the lower limit rotational speed until Therefore, in response to the change in increasing the target temperature, the amount of heat supplied from the bathroom heating device into the bathroom increases without a delay time, and the temperature in the bathroom is quickly raised to the target temperature after the change. You can

A second aspect of the present invention is to eliminate the inconvenience that occurs when the rotation speed range setting means for setting the control range of the rotation speed of the fan is provided. That is, the rotation speed range setting means shifts the rotation speed range of the fan to a high rotation speed range within the predetermined time during which the fan is rotating at the low speed rotation speed set lower than the lower limit rotation speed. When the change is made, the control range of the rotation speed of the fan is shifted to a high rotation range until the predetermined time elapses. Since the rotational speed is maintained at the low rotational speed, there is a time lag until the rotational speed of the fan starts to increase, which causes an inconvenience to the bather.

Therefore, a second aspect of the present invention is provided with a rotation speed range setting means for setting a control range of the rotation speed of the fan in the heating operation, and the heating control means has the rotation speed within the predetermined time. When the number range setting means changes the control range of the rotation speed of the fan to a high rotation direction, the lower limit rotation speed of the fan is kept until the detected temperature of the bathroom temperature sensor becomes equal to or higher than the target temperature. It is characterized in that it is operated at the above rotational speed.

According to the present invention, when the rotation speed range setting means changes the control range of the rotation speed of the fan to the high rotation direction within the predetermined time, the heating control means is controlled by the heating control means. The fan is rotated at a rotational speed equal to or higher than the lower limit rotational speed until the temperature detected by the bathroom temperature sensor becomes equal to or higher than the target temperature. Therefore, the number of rotations of the fan can be quickly increased without a delay time according to the change in increasing the control range of the number of rotations of the fan in the high rotation direction.

Further, in a third aspect of the present invention, the temperature in the bathroom sharply drops within the predetermined time period during which the fan is rotating at the low speed rotation speed set lower than the lower limit rotation speed. The purpose is to eliminate the inconvenience that may occur. That is, if, for example, a bather opens a window in the bathroom for ventilation within the predetermined time, outside air flows into the bathroom and the temperature in the bathroom sharply drops. In this case, the rotation speed of the fan is maintained at the low rotation speed until the predetermined time elapses, so that the lowered temperature in the bathroom is unlikely to rise and the temperature in the bathroom remains low. Then there is the inconvenience that the bather feels cold.

Therefore, according to a third aspect of the present invention, when the heating control means recognizes that the temperature detected by the bathroom temperature sensor has decreased from the target temperature by a predetermined temperature range or more within the predetermined time, The fan is operated at a rotation speed equal to or higher than the lower limit rotation speed until the detected temperature of the bathroom temperature sensor becomes equal to or higher than the target temperature.

According to the present invention, when the detected temperature of the bathroom temperature sensor falls from the target temperature by the predetermined temperature range or more within the predetermined time, the heating control means causes the detected temperature of the bathroom temperature sensor to be the above-mentioned. The fan is operated at a rotational speed equal to or higher than the lower limit rotational speed until the target temperature or higher is reached. Therefore, when the temperature in the bathroom sharply decreases, the rotation speed of the fan increases, and the temperature in the bathroom can be quickly returned to the target temperature.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an installation state of a bathroom heating device of the present invention, FIG. 2 is an overall configuration diagram of the bathroom heating device shown in FIG. 1, and FIG. 3 is a switching of the speed of a circulation fan during heating operation and the inside of the bathroom. Graphs showing changes in temperature, FIGS. 4 and 5 are execution flowcharts of the heating operation.

Referring to FIG. 1, a bathroom heating device 1 has a bathtub 2
It is installed on the ceiling part of the bathroom 3 provided with, and is operated by the electric power supplied from the outlet 4 of the commercial power source through the breaker 5. The bathroom heating device 1 is communicatively connected to the heat source device 6 by a heat source device cable 7, and hot water of a predetermined temperature is supplied from the heat source device 6 to the bathroom heater 1 through the hot water supply pipe 8a. Heat source unit 6 via return pipe 8b
Return to.

Further, the bathroom heating device 1 is communicated with an intermediate duct 9 for ventilating the bathroom 3, and a remote control 11 for setting an operation mode or the like via a remote control cable 10 (target of the present invention). (Including functions of temperature setting means and rotation speed range setting means) are connected.

Next, referring to FIG. 2, bathroom heating device 1
Is a controller 20 that controls the overall operation of the bathroom heating device 1 (including the function of the heating control means of the present invention), and a heat exchanger that heats air using the hot water supplied through the hot water supply pipe 8a as a heat source. 21, a heat valve 22 that opens and closes the hot water supply pipe 8a, and a circulation fan 24 that heats the air taken in from the intake port 23 by the heat exchanger 21 and sends it as warm air into the bathroom.
It is supplied from a fan motor 25 for operating the circulation fan 24 (corresponding to the fan of the present invention), a looper 26 for setting the direction of the air to be sent out, a looper motor 27 for operating the looper 26, and a heat source device 6. A hot water thermistor 28 for detecting the temperature of hot water, a room temperature thermistor 29 (corresponding to the bathroom temperature sensor of the present invention) for detecting the temperature of the air in the bathroom (= the temperature of the bathroom) sucked from the intake port 23, and an earth leakage breaker 30. , A remote controller connector 31, a heat source device connector 32, a power source connector 33, and an intermediate duct fan connector 34.

An intermediate duct fan 40 is installed in the middle of the intermediate duct 9, and the controller 20 sends a control signal to the intermediate duct fan 40 via the intermediate duct fan connector 34 and the intermediate duct fan cable 41. This controls the operation / stop of the intermediate duct fan 40.

The controller 20 operates in accordance with the operation of an operation mode changeover switch (not shown) provided on the remote controller 11 to show "heating", "cool air", "drying", "ventilation", And the bathroom heating device 1 is operated in each operation mode of "freezing prevention".

[0024]

[Table 1]

The remote controller 11 has a circulation fan 24.
Air volume control switch (corresponding to the rotational speed control range of the present invention) in three steps of "strong", "weak", and "fine" (not shown, rotational speed of the present invention) (Corresponding to range setting means) and a temperature changeover switch (not shown, corresponding to target temperature setting means of the present invention) for setting the target temperature in the heating mode in three stages of "high", "medium", and "low" Is provided.

Then, the controller 20 switches the rotation speed of the circulation fan 24 in the heating mode from the first speed to the sixth speed in accordance with the operation of the air volume changeover switch and the temperature changeover switch, as shown in Table 2 below. Set in 6 steps.
The higher the speed number, the higher the rotation speed of the circulation fan 24 is set.

[0027]

[Table 2]

Then, as shown in Table 2, in the heating mode, the controller 20 switches the speed of the circulation fan 24 in four types of cycles of heating 0 to heating 3, and each cycle (heating 0 to heating 3). ) Is set based on Table 2 above.

Here, the room temperature thermistor 29 is provided in the inflow path of the air in the bathroom sucked from the intake port 23 by the circulation fan 24, and when the rotation speed of the circulation fan 24 is low, the air in the bathroom is reduced. Becomes insufficient, a difference occurs between the actual temperature in the bathroom and the temperature detected by the room temperature thermistor 29, and the room temperature cannot be detected accurately.

In the present embodiment, in the fourth to sixth speeds, the actual temperature inside the bathroom and the temperature detected by the room temperature thermistor 29 are substantially the same, and the temperature inside the bathroom can be detected accurately. The rotation speed is set higher than the lower limit rotation speed at which the air volume can be secured. Therefore, the controller 20
Basically, the room temperature thermistor 29 detects the temperature in the bathroom when the circulation fan 24 is rotating at the fourth speed or higher.

In the heating mode, the controller 20
Detects the temperature in the bathroom with the room temperature thermistor 29, and the temperature in the bathroom is set to “high”, “medium”,
A heating operation is performed in which the speed of the circulation fan 24 is switched so that the target temperature preset corresponding to "low" is maintained. Hereinafter, the operation of the controller 20 in the heating operation will be described.

When the user sets the operation mode changeover switch (not shown) provided on the remote controller 11 to "heating" and turns on the operation switch (not shown), the controller 20 opens the thermal valve 22. At the same time, the control signal for instructing the start of operation is transmitted to the heat source device 6 via the heat source device cable 7.

As a result, the heat source device 6 is activated, and the supply of hot water of a predetermined temperature (for example, 80 ° C.) from the heat source device 6 to the heat exchanger 21 is started via the hot water supply pipe 8a. And
In order to prevent the cool air from being supplied to the bathroom, the controller 20 waits for the temperature detected by the hot water thermistor 28 to reach a predetermined level or higher (for example, 40 ° C. or higher), and then operates the circulation fan 24 to enter the bathroom. To start sending hot air.

FIG. 3 is a graph showing changes in the speed of the circulation fan 24 and room temperature when the heating operation is started with the air volume set to "strong" and the temperature set to "high", and the horizontal axis represents Time (t), the vertical axis indicates from the top the speed of the circulation fan 24 (1st speed to 6th speed).
Speed), ON / OFF of the thermal valve 22, and temperature in the bathroom. Referring to FIG. 3, at time t ₀ when an instruction for heating operation is given, controller 20 opens thermal valve 22 to operate heat source device 6, as described above.

Then, at time t ₁ when the temperature detected by the hot water thermistor 28 becomes equal to or higher than a predetermined level, the circulation fan 24 starts to rotate and the temperature detected by the room temperature thermistor 29 reaches the target temperature (Ta) until the temperature reaches the target temperature (Ta). Performs "2 heating cycles" in which is rotated at 6th speed.

Next, the controller 20 rotates from the time t ₂ when the detected temperature of room temperature thermistor 29 becomes a target temperature (Ta) or only during the circulation fan 24 the fourth speed at time T1 "Heating 3 cycles" The temperature detected by the room temperature thermistor 29 is compared with the target temperature (Ta) at time t ₃ when the “heating 3 cycles” are completed. In this way, the controller 20 causes the bather to get cold due to drafts and cold radiation from the wall surface by reducing the number of revolutions of the circulation fan 24 in stages to suppress the rapid decrease in the amount of warm air delivered. It reduces the feeling.

In the graph of FIG. 3, the temperature detected by the room temperature thermistor 29 exceeds the target temperature (Ta) at time t ₃ .
This means that even if the speed of the circulation fan 24 is reduced to the fourth speed, the amount of heat supplied from the bathroom heating device 1 into the bathroom is excessive. Therefore, from time t ₃ , the controller 20 executes a “heating 0 cycle” in which the circulation fan 24 is rotated at the third speed for the time T 2 to reduce the amount of heat supplied to the bathroom and raise the temperature in the bathroom. Is suppressed.

As described above, when the speed is 3 or less,
The room temperature thermistor 29 accurately detects the temperature in the bathroom.
Can not do it. Therefore, the controller 20
Time t when the "heating 0 cycle" ends_FourFrom the circulation fa
Rotate the engine 24 at 4th speed for time T3
The time when the "cycle" is executed and the "heating 1 cycle" is completed
t _FiveThen, the detected temperature of the room temperature thermistor 29 is set to the target temperature (T
Compare with a).

In the graph of FIG. 3, the temperature detected by the room temperature thermistor 29 is lower than the target temperature (Ta) -2 ° C. at time t ₅ . Therefore, the controller 20 sets the time t ₅
From increasing the amount of heat supplied to the the bathroom run the "heating 2 cycle" again to exit the "heating 2 cycle" at time t ₆ the temperature detected by the room temperature thermistor 29 has reached the target temperature (Ta) , The “heating 3 cycle” is executed from time t ₆ .

On the other hand, at time t ₅ , the temperature detected by the room temperature thermistor 29 is the target temperature (Ta) -2 ° C. or higher and the target temperature (T
a) When it is within the following range, it can be determined that the amount of heat supplied to the bathroom is appropriate.
Does not change the amount of heat supplied to the bathroom by executing "heating 1 cycle" again.

When the detected temperature of the room temperature thermistor 29 exceeds the target temperature (Ta) at time t ₅ , the controller 20 executes the "heating 0 cycle" again in order to lower the temperature in the bathroom. In this way, by setting the speed of the circulation fan 24 in accordance with the temperature detected by the room temperature thermistor 29 at time t ₅ , the controller 20
Keeps the temperature in the bathroom near the target temperature (Ta).

Next, in the "heating 0 cycle", the circulation fan 24 is rotating at the third speed, and the controller 20 controls the temperature in the bathroom by the room temperature thermistor 29 until the next "heating 1 cycle" is entered. It cannot be detected accurately.

However, during execution of the "heating 0 cycle",
It is conceivable that the user operates the remote controller to change the air volume and temperature settings. Then, in this case, if the process according to the changed setting is not performed until the “heating 0 cycle” ends, a time delay occurs until the change result is reflected in the heating operation, and the user There is an inconvenience that it gives a feeling of strangeness.

It is also conceivable that the user may open the window of the bathroom to perform ventilation while the "heating 0 cycle" is being executed.
In this case, the temperature in the bathroom sharply drops due to the outside air, but when the "heating 0 cycle" is continued, the rotation speed of the circulation fan 24 remains low despite the temperature in the bathroom dropping. There is an inconvenience that the bather feels cold as the temperature in the bathroom is not recovered.

Therefore, in order to eliminate these inconveniences,
The controller 20 performs the processing shown in the flowcharts of FIGS. 4 to 5 to execute the “heating 0 cycle”. Figure 4
Referring to, the controller 20 starts a timer (hereinafter, referred to as T2 timer) that sets the rotation speed of the circulation fan 24 to the third speed in STEP1 and sets the set time to T2 in STEP2, and executes "heating 0 cycle". To start.

Then, the controller 20 uses STEP3
In step 4, it is confirmed whether the user has set the temperature to be increased, and in STEP 4, it is confirmed whether the user has set the air volume to be increased, and in step 5, the room temperature thermistor 29.
Waiting for the T2 timer to time up in STEP6 while confirming whether the detected temperature of 1 has become lower than the target temperature (Ta) -3 ° C.

When the T2 timer times out in STEP6, the controller 20 finishes "heating 0 cycle" and proceeds to STEP 7 to execute "heating 1 cycle". On the other hand, when the temperature is changed by the user in STEP 3, when the air volume is changed by the user in STEP 4, and in STEP 5, the detected temperature of the room temperature thermistor 29 is the target temperature (Ta) -3 ° C (main (Corresponding to the predetermined temperature range of the invention),
Branch to STEP 10.

Then, the controller 10 uses STEP1
At 0, the rotation speed of the circulation fan 24 is increased to the 6th speed, and the air in the bathroom circulates to wait for the temperature detected by the room temperature thermistor 29 to substantially match the actual temperature in the bathroom. Start the 2 minute timer with. Then, in STEP 12, when the 2-minute timer times out, the process proceeds to STEP 13 and the controller 20 confirms whether or not the temperature detected by the room temperature thermistor 29 exceeds the target temperature (Ta).

If the temperature detected by the room temperature thermistor 29 exceeds the target temperature (Ta) in STEP 13, it can be determined that the current amount of heat supplied to the bathroom is excessive with respect to the target temperature (Ta). , The controller 20 is S in FIG.
Return to TEP1 and execute the "heating 0 cycle" again.

Further, in STEP 13, the room temperature thermistor 29
When the detected temperature of is less than or equal to the target temperature (Ta), S
Branching to the TEP 20, the controller 20 confirms whether or not the temperature detected by the room temperature thermistor 29 is the target temperature (Ta) −2 ° C. or higher. When the detected temperature of the room temperature thermistor 29 is equal to or higher than the target temperature (Ta) -2 ° C,
Since it can be determined that the heat supply from the bathroom heating device 1 to the bathroom is appropriate, the process proceeds to STEP 21 and the controller 2
0 is the "heating 1
Cycle.

On the other hand, in STEP 20, the room temperature thermistor 2
When the detected temperature of 9 is lower than the target temperature (Ta) −2 ° C., it can be determined that the supply of the amount of heat from the bathroom heating device 1 into the bathroom is insufficient, so the process branches to STEP 30, and the controller 20 The number of rotations of the circulation fan 24 is 3
Execute the "heating 2 cycle" that has been stepped up. As a result, in the "heating 0 cycle", when the temperature of the bathroom is changed or the amount of air flow is increased by the user, and when the temperature of the bathroom suddenly decreases, the temperature of the bathroom is set to the target temperature (Ta). Can be quickly raised to.

In this embodiment, as shown in FIGS. 4 to 5, during execution of the "heating 0 cycle" in which the circulation fan 24 is rotated at a rotation speed lower than the lower limit rotation speed,
When the user changes the temperature (STE
P3), when the air volume is changed by the user (STEP 4), and when the temperature detected by the room temperature thermistor 29 becomes lower than the target temperature (Ta) -3 ° C (ST).
Although the process shown in FIG. 5 is performed after confirming the success or failure of the three conditions of EP5), the present invention is not limited to the case of confirming the success or failure of at least one of these three conditions. Can benefit from.

Further, although the bathroom heating device installed on the ceiling surface of the bathroom is shown in the present embodiment, the present invention can be applied to a wall-hanging type bathroom heating device installed on the wall surface of the bathroom. is there.

Further, in the present embodiment, the speed of the circulation fan 24 is switched in four stages of "heating 0 cycle" to "heating 3 cycles" in the heating operation, but it may be switched to more stages. Good.

[Brief description of drawings]

FIG. 1 is a diagram showing an installed state of a bathroom heating device.

FIG. 2 is an overall configuration diagram of the bathroom heating device shown in FIG.

FIG. 3 is a graph showing changes in the speed of the circulation fan and changes in the bathroom temperature during heating operation.

FIG. 4 is an execution flowchart of “heating 0 cycle”.

FIG. 5 is an execution flowchart of “heating 0 cycle”.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bathroom heating device, 3 ... Bathroom, 6 ... Heat source machine, 9 ... Intermediate duct, 11 ... Remote control, 20 ... Controller, 21 ... Heat exchanger, 22 ... Heat valve, 24 ... Circulation fan, 28 ... Hot water thermistor, 29 ... Room temperature thermistor

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3L061 BE02 BF02 BF06                 3L072 AA06 AB06 AC01 AD02 AE01                       AF01 AG01

Claims (3)

[Claims] 1. A heat exchanger using hot water supplied at a predetermined temperature as a heat source, and a fan that sucks air to pass through the heat exchanger and blows the air passing through the heat exchanger into a bathroom. , A bathroom temperature sensor provided in an inflow path of air sucked by the fan, and by operating the fan in a state where hot water is supplied to the heat exchanger, the heat is passed through the heat exchanger and heated. And heating control means for performing heating operation for controlling the number of rotations of the fan so that the detected temperature of the bathroom temperature sensor matches a predetermined target temperature. Is the temperature detected by the bathroom temperature sensor even when the number of rotations of the fan is lowered to the lower limit number of rotations that produces an air volume at which the temperature in the bathroom can be detected by the bathroom temperature sensor during execution of the heating operation. When the temperature exceeds the target temperature, in the bathroom heating device that operates the fan for a predetermined time at a low rotation speed set lower than the lower limit rotation speed, a target temperature setting means for setting the target temperature is provided, and the heating control When the target temperature setting unit changes the target temperature to increase within the predetermined time, the means keeps the fan at the lower limit rotation speed or more until the detected temperature of the bathroom temperature sensor becomes the target temperature or more. Bathroom heating system characterized by operating at the number of rotations of. 2. A heat exchanger that uses hot water supplied at a predetermined temperature as a heat source, and a fan that sucks air to pass through the heat exchanger and blows the air passing through the heat exchanger into the bathroom. , A bathroom temperature sensor provided in an inflow path of air sucked by the fan, and by operating the fan in a state where hot water is supplied to the heat exchanger, the heat is passed through the heat exchanger and heated. And heating control means for performing heating operation for controlling the number of rotations of the fan so that the detected temperature of the bathroom temperature sensor matches a predetermined target temperature. Is the temperature detected by the bathroom temperature sensor even when the number of rotations of the fan is lowered to the lower limit number of rotations that produces an air volume at which the temperature in the bathroom can be detected by the bathroom temperature sensor during execution of the heating operation. When the temperature exceeds the target temperature, in the bathroom heating device that operates the fan for a predetermined time at a low rotation speed set lower than the lower limit rotation speed, a rotation setting a control range of the rotation speed of the fan in the heating operation. The heating control means includes a number range setting means, and the heating control means changes the control range of the rotation speed of the fan to a high rotation direction by the rotation speed range setting means within the predetermined time when the bathroom temperature is changed. A bathroom heating device, characterized in that the fan is operated at a rotational speed equal to or higher than the lower limit rotational speed until the temperature detected by the sensor becomes equal to or higher than the target temperature. 3. A heat exchanger using hot water supplied at a predetermined temperature as a heat source, and a fan that sucks air to pass through the heat exchanger and blows the air passing through the heat exchanger into the bathroom. , A bathroom temperature sensor provided in an inflow path of air sucked by the fan, and by operating the fan in a state where hot water is supplied to the heat exchanger, the heat is passed through the heat exchanger and heated. And heating control means for performing heating operation for controlling the number of rotations of the fan so that the detected temperature of the bathroom temperature sensor matches a predetermined target temperature. Is the temperature detected by the bathroom temperature sensor even when the number of rotations of the fan is lowered to the lower limit number of rotations that produces an air volume at which the temperature in the bathroom can be detected by the bathroom temperature sensor during execution of the heating operation. When the temperature exceeds the target temperature, in the bathroom heating device for operating the fan for a predetermined time at a low rotation speed set lower than the lower limit rotation speed, the heating control means, the heating temperature of the bathroom temperature sensor within the predetermined time. When it is understood that the detected temperature has dropped from the target temperature by a predetermined temperature range or more, the fan is operated at a rotation speed equal to or higher than the lower limit rotation speed until the detection temperature of the bathroom temperature sensor becomes equal to or higher than the target temperature. A bathroom heating system characterized by the above.