JP2924998B2 - Hot air heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot air heater.

[0002]

2. Description of the Related Art Conventionally, a combustion chamber accommodating a gas burner as a heating source, a heat exchange section connected to the combustion chamber, an air passage having a heat exchange section and communicating with a suction port and an air outlet, 2. Description of the Related Art There is known an FF type gas warm air heater in which a convection fan disposed in a passage is disposed in a main body case.

In this gas hot air heater, an intake cylinder extending outside the main body case is connected to the upstream side of the combustion chamber,
An exhaust pipe is connected to the downstream side via a heat exchange section. The convection fan sucks the room air through the suction port and sends the room air heated by the heat exchange section into the room from the outlet. The room temperature sensor is disposed, for example, near the suction port, and the room temperature setting device is provided in the operation unit of the main body case.

[0004] The combustion controller adjusts the opening of the proportional valve provided in the gas supply path in a stepless manner or in a plurality of steps so that the temperature detected by the temperature sensor becomes the target temperature set by the room temperature setting device. Controlling. However, in the case of a warm air heater with a large maximum combustion amount, even if the combustion controller minimizes the gas burner combustion amount, the room temperature may exceed the set temperature. For example, when setting low.

[0005] This situation can be solved by providing a combustion controller for temporarily stopping the combustion of the gas burner when the detected room temperature exceeds a predetermined temperature. Specifically, the detected room temperature during combustion,
When the temperature exceeds the first reference temperature determined according to the set room temperature, the combustion controller stops the combustion of the gas burner. Thereafter, when the detected room temperature falls below the second reference temperature lower than the first reference temperature, the combustion restarts.

[0006]

However, the present inventors have found that the hot air heater provided with the above-mentioned combustion controller has the following disadvantages. In the hot air heater, when the combustion of the gas burner is stopped, the operation of the convection fan is continued until a predetermined time elapses or until the temperature in the machine falls below the predetermined temperature (so-called post-purge). We are trying to prevent overheating.

During the post-purge, the convection fan operates, and the room air flows through the room temperature sensor, so that the room temperature can be accurately detected. However, when the post-purge is completed, the convection fan stops, and the room air stops flowing to the room temperature sensor.

For this reason, the change in the detected room temperature detected by the room temperature sensor after the end of the post-purge usually deviates from the actual change in the room temperature (see the solid line and the two-dot chain line in FIG. 4). Accordingly, a phenomenon occurs in which the room temperature detected by the room temperature sensor exceeds the second reference temperature even though the actual room temperature falls below the second reference temperature and the time has come to restart combustion. In this case, the user feels cold because combustion is not resumed.

If the convection fan is operated continuously or intermittently even after the end of the post-purge, the above phenomenon does not occur, but the cool air is blown out from the warm air heater to give a user discomfort. Note that, in the above-described conventional technology, a gas burner is shown as a heating source, but there is a similar problem even if the heating source is an electric heater or the like.

[0010] It is an object of the present invention to temporarily stop the operation of the heating source when the detected room temperature exceeds a predetermined temperature, and to continuously operate the convection fan for a predetermined time or until the inside temperature of the apparatus falls below the predetermined temperature. In a hot air heater that performs post-purging, room temperature control is appropriately performed without causing discomfort to a user.

[0011]

In order to solve the above-mentioned problems,
The present invention employs the following configuration. (1) A housing having a suction port and an air outlet, a heating source disposed in the housing, and room air sucked from the air inlet, and the room air heated by the heating source is heated as hot air from the air outlet. A convection fan to be blown out, a room temperature sensor arranged near the suction port for detecting room temperature, a room temperature setting device for setting room temperature, and first and second reference temperatures are determined based on the set room temperature. Having a reference temperature determination unit, when the detected room temperature exceeds the first reference temperature, temporarily suspend the operation of the heating source, for a predetermined time, perform a post-purge to continue operating the convection fan, When the detected room temperature falls below a second reference temperature lower than the first reference temperature during the stop of the heating, a heating control means for restarting the operation of the heating source is provided. Control means, when the post-purge is completed, the second reference temperature, it has a reference temperature changing unit that changes a temperature higher than the second reference temperature during post-purge.

(2) A housing having a suction port and an air outlet, a heating source disposed in the housing, and indoor air sucked from the suction port, and the room air heated by the heating source is converted into warm air. A convection fan that blows out from the outlet, a room temperature sensor that is disposed near the suction port and detects a room temperature, a room temperature setting device that sets a room temperature, and a first and second reference temperature based on the set room temperature. When the detected room temperature exceeds the first reference temperature, the operation of the heating source is temporarily stopped, and until the in-machine temperature decreases to a predetermined temperature or less, A post-purge for continuously operating the convection fan is performed, and when the detected room temperature falls to or below the second reference temperature lower than the first reference temperature during this heating stop, a heating control means for restarting the operation of the heating source. In the warm-air heating machine having a door,
When the post-purge is completed, the heating control means
A reference temperature changing unit configured to change the second reference temperature to a temperature higher than the second reference temperature during the post-purge.

(3) The first reference temperature having the configuration of the above (1) or (2), wherein the first reference temperature determined by the reference temperature determination section is higher than a set room temperature set by the room temperature setting device, and The second reference temperature determined by the determination unit is equal to the set room temperature set by the room temperature setting device, and the second reference temperature changed by the reference temperature change unit is equal to the first reference temperature.

(4) A housing having a suction port and an air outlet, a heating source disposed in the housing, and room air sucked from the suction port, and the room air heated by the heating source is turned into hot air. A convection fan that blows out from the outlet, a room temperature sensor that is disposed near the suction port and detects a room temperature, a room temperature setting device that sets a room temperature, and a first and second reference temperature based on the set room temperature. A post-purge for temporarily stopping the operation of the heating source and continuously operating the convection fan for a predetermined time when the detected room temperature exceeds the first reference temperature. When the detected room temperature falls below the second reference temperature lower than the first reference temperature during the heating stop, a heating control means for restarting the operation of the heating source is provided. Te, the heating control means, when the post-purge is completed, the detecting room temperature correction to the said temperature lower than the temperature detected by the temperature sensor is compared with the second reference temperature.

(5) A housing having a suction port and an air outlet, a heating source disposed in the housing, and room air sucked from the suction port, and the room air heated by the heating source is converted into warm air. A convection fan that blows out from the outlet, a room temperature sensor that is disposed near the suction port and detects a room temperature, a room temperature setting device that sets a room temperature, and a first and second reference temperature based on the set room temperature. When the detected room temperature exceeds the first reference temperature, the operation of the heating source is temporarily stopped, and until the in-machine temperature decreases to a predetermined temperature or less, A post-purge for continuously operating the convection fan is performed, and when the detected room temperature falls to or below the second reference temperature lower than the first reference temperature during this heating stop, a heating control means for restarting the operation of the heating source. In the warm-air heating machine having a door,
When the post-purge is completed, the heating control means
The detected room temperature is corrected to a temperature lower than the temperature detected by the room temperature sensor and is compared with the second reference temperature.

[0016]

[Action and effect of the invention]

[Concerning Claims 1 and 2] The convection fan draws indoor air from the inlet, and the room air heated by the heating source is blown out from the outlet as warm air. The reference temperature determining section of the heating control means determines a first reference temperature and a second reference temperature based on the set room temperature set by the room temperature setting device. The heating control means temporarily stops the operation of the heating source when the detected room temperature exceeds the first reference temperature, and for a predetermined period of time. Meanwhile, post-purge is performed to continuously operate the convection fan.

During the post-purge, since the convection fan is rotating, the room air flows to the room temperature sensor disposed near the suction port, and the room temperature is accurately detected. Then, when the detected room temperature falls below the second reference temperature during the post-purge, the heating control means restarts the operation of the heating source.

If a predetermined period of time before the detected room temperature does not drop to the second reference temperature (in the case of claim 2 until the internal temperature of the apparatus falls below the predetermined temperature) has elapsed, the post-purge is terminated. Since the rotation of the convection fan stops, the room air does not flow to the room temperature sensor. For this reason, the detected room temperature detected by the room temperature sensor is detected higher than the actual room temperature. However, when the post-purge is completed, the reference temperature change unit changes the second reference temperature to a temperature higher than the second reference temperature during the post-purge, so that the actual room temperature has dropped to the point where the operation of the heating source should be resumed. At a point near the state, the heating control means restarts the operation of the heating source.

As described above, in the warm air heater adopting this configuration, since the room temperature control is performed appropriately, the user does not feel cold. Further, since no cool air is blown out, the user does not feel uncomfortable.

[Claim 3] The convection fan draws indoor air from the inlet, and the room air heated by the heating source is blown out from the outlet as warm air. The reference temperature determining unit of the heating control means determines the first reference temperature to be higher than the set room temperature and sets the second reference temperature to the same temperature as the set room temperature, based on the set room temperature set by the room temperature setter.

When the detected room temperature exceeds the first reference temperature, the heating control means temporarily stops the operation of the heating source and waits for a predetermined period of time (or until the temperature inside the device falls below the predetermined temperature). Then, post-purge is performed to continuously operate the convection fan.

During the post-purge, since the convection fan is rotating, the room air flows to the room temperature sensor disposed near the suction port, and the room temperature is accurately detected. Then, when the detected room temperature falls below the second reference temperature (= below the set room temperature) during the post-purge, the heating control means restarts the operation of the heating source.

When a predetermined period of time before the detected room temperature does not decrease to the second reference temperature (= set room temperature) (in the case of the second aspect, until the temperature inside the machine falls below the predetermined temperature), the post After the purge is completed, the rotation of the convection fan stops, so that the room air does not flow to the room temperature sensor.
For this reason, the detected room temperature detected by the room temperature sensor is detected higher than the actual room temperature.

However, when the post-purge is completed, the reference temperature change unit changes the second reference temperature to the first reference temperature higher than the second reference temperature (= set room temperature) during the post-purge, so that the actual room temperature is changed. When the temperature drops to a temperature at which the operation of the heating source should be restarted, the heating control means restarts the operation of the heating source.

As described above, in the warm air heater adopting this configuration, since the room temperature control is appropriately performed, the user does not feel cold. Further, since no cool air is blown out, the user does not feel uncomfortable.

[Claims 4 and 5] The convection fan is
Room air is drawn in from the inlet, and the room air heated by the heating source is blown out from the outlet as warm air. The reference temperature determining section of the heating control means determines a first reference temperature and a second reference temperature based on the set room temperature set by the room temperature setting device. When the detected room temperature exceeds the first reference temperature, the heating control means temporarily stops the operation of the heating source and performs post-purge for continuously operating the convection fan for a predetermined time.

During the post-purge, the convection fan is rotating, so that room air flows to the room temperature sensor disposed near the suction port, and the room temperature is accurately detected. Then, when the detected room temperature falls below the second reference temperature during the post-purge, the heating control means restarts the operation of the heating source.

If a predetermined period of time before the detected room temperature does not decrease to the second reference temperature (in the case of claim 4 until the internal temperature of the apparatus falls below the predetermined temperature) has elapsed, post-purge is terminated. Since the rotation of the convection fan stops, the room air does not flow to the room temperature sensor. For this reason, the detected room temperature detected by the room temperature sensor is detected higher than the actual room temperature. However, when the post-purge is completed, the heating control unit corrects the detected room temperature to a temperature lower than the temperature detected by the temperature sensor and compares the corrected room temperature with the second reference temperature, so that the actual room temperature resumes the operation of the heating source. The operation of the heating source is restarted at a point near the state where the temperature to be lowered has been reached.

As described above, in the warm air heater adopting this configuration, since the room temperature control is appropriately performed, the user does not feel cold. Further, since no cool air is blown out, the user does not feel uncomfortable.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention (corresponding to claims 1 and 3) will be described with reference to FIGS. The FF type gas hot air heater A shown in the figure has a housing 1 having an inlet 11 and an outlet 12, a combustor 2 to which gas is supplied and burns,
Convection fan 3 for blowing hot air 30 from outlet 12
A room temperature sensor 4 for detecting a room temperature, a room temperature setting device 5 for setting a room temperature, a first combustion control means 6 for instructing a combustion amount of the combustor 2, and a first reference temperature T ₁ based on the set room temperature Ts.
And a reference temperature determining unit 71 for setting the second reference temperature T ₂ ,
And a reference temperature change unit 72 for changing the second reference temperature T _{2 when} the post-purge is completed, and the second combustion control means 7 for instructing continuation or stop of combustion of the combustor 2 and operation or stop of the convection fan 3. (Heating control means). 8 is a combustion fan, 9 is a control unit, 13 is a hot air passage, 14
Is a combustion air passage.

The hot air passage 13 has a suction opening 11 opened at the upper rear part of the housing 1 to suck the room air 10 and an outlet 12 opened at the lower front part of the housing 1 to blow the warm air 30 into the room. It is a communication passage. A filter 111 for removing dust in the room is detachably provided at the suction port 11, and a guide plate 301 for changing a blowing direction of the warm air 30 is attached to the outlet 12.

The combustion air passage 14 is a passage whose upstream end and downstream end communicate with the intake and exhaust ports of a double-structured intake / exhaust duct extending outside, respectively. A heat exchange section 141 for releasing the heat of the combustion chamber 21 provided therein and the combustion exhaust gas 22 generated by the combustion into the airflow 15 is formed in the passage. The combustion chamber 21 and the heat exchange unit 14
1 is located in the hot air passage 13.

The combustor 2 has a flame outlet 231 for discharging an air-fuel mixture.
Are formed at the front end, and gas burners 23, 23... Formed at the base end with a mixture inlet 232 for sucking primary air and gas.
And the nozzle 2 in the gas mixture inlet 232 of the gas burner 23.
41, 241,..., And a solenoid valve 25, 26 and a gas proportional valve 27 are sequentially provided in the gas pipe 24.
Gas is supplied by the gas line g connected continuously and is forcibly burned. The sparker 28 is arranged facing the gas burner 23, and ignites the gas burner 23 when a high voltage is applied by the sparker drive circuit 281 during the ignition operation.

The combustion fan 8 includes an impeller 81 pivotally mounted in the combustion air passage 14 upstream of the combustor 2 with respect to the flow of air, and a combustion fan motor 8 for driving the impeller 81.
2 (DC motor) and the indoor air 1
0 is supplied to the gas burner 23. This combustion fan 8
Electricity is supplied through the combustion fan drive circuit 821, the engine rotates at the ignition speed during ignition, and the temperature control speed (1300 rpm or more) at which the combustion air corresponding to the required combustion amount is obtained during temperature control.
3600 rpm).

The gas proportional valve 27 is a valve whose opening is controlled in accordance with the amount of energization. When the amount of energization increases, the amount of gas supplied to the combustor 2 increases. When the solenoid valves 25 and 26 are energized via the solenoid valve drive circuit 251, the valve is opened and gas is supplied to the gas burner 23.

Further, a proportional valve current of the ignition level is supplied to the gas proportional valve 27 via the proportional valve drive circuit 271 at the time of ignition, and the temperature control level corresponding to the temperature control rotation speed of the combustion fan 8 at the time of temperature control. Is flowed. A flame rod 29 faces the combustion flame and detects a flame current.

The convection fan 3 comprises an impeller 31 pivotally mounted in the hot air passage 13 near the suction port 11 and a convection fan motor 32 (AC motor) for driving the impeller 31. , An air flow 15 directed toward the outlet 12 is generated. At the time of temperature control, a current is supplied to the convection fan 3 via the convection fan drive circuit 33 at a level at which an air flow proportional to a required combustion amount is obtained.

As shown in FIG. 2, the control unit 9 includes a proportional valve driving circuit 271 for driving the gas proportional valve 27, an electromagnetic valve driving circuit 251 for closing and opening the solenoid valves 25 and 26, and a convection fan motor. Convection fan drive circuit 33 for driving
A combustion fan drive circuit 821 for feedback controlling the combustion fan motor 82; a sparker drive circuit 281 for driving the sparker 28; a first combustion control means 6 and a second combustion control means 7; It has a microcomputer 50 for controlling each of the above driving circuits based on each electric signal transmitted by the sensor 4, the room temperature setting device 5, the frame rod 29 and the like.

During the temperature control, the first combustion control means 6 sets (the set room temperature Ts set by the room temperature setting device 5)-(the room temperature sensor 4).
The combustion fan drive circuit calculates a required combustion amount based on the detected room temperature T detected by the controller and rotates at a temperature control rotation speed (1300 to 3600 rpm) at which combustion air corresponding to the required combustion amount is obtained. Combustion fan 8 via 821
Feedback control.

Further, the first combustion control means 6 detects the number of revolutions of the combustion fan 8 at the time of temperature adjustment, and calculates the required amount of combustion by back calculation based on the detected number of revolutions, thereby obtaining the required amount of combustion. The energization of the gas proportional valve 27 is controlled via the proportional valve drive circuit 271 so that the opening degree is obtained.

In this embodiment, the reference of the second combustion control means 7
The temperature determining unit 71 determines the set room temperature T set by the room temperature setting device 5.
s, the first reference temperature T₁Set room temperature Ts + 0.3
3 ° C, second reference temperature T_TwoSet room temperature T_SEach decide
You. Note that the reference temperature changing unit 72 of the second combustion control means 7
When the post-purge described later is completed, the second reference temperature T _Two
From the set room temperature Ts to the set room temperature Ts + 0.33 ° C
You.

When the detected room temperature T exceeds the set room temperature Ts + 0.33 ° C. at the time of temperature control, the second combustion control means 7 gives an instruction to stop the combustion of the combustor 2 once, and for 150 seconds. An instruction to perform post-purge for continuously operating the convection fan 3 is issued. Then, when the detected room temperature T falls below the set room temperature Ts during this combustion stop, the second combustion control means 7 instructs the combustion of the combustor 2 to restart.

Next, the operation of the FF type gas hot air heater A will be described based on the flowchart shown in FIG. 3 and the graph shown in FIG. The reference temperature determination unit 71 of the second combustion control means 7 of the control unit 9 sets the first reference temperature T ₁ based on the set room temperature Ts set by the room temperature setter 5.
s + 0.33 ° C. and the second reference temperature T ₂ are determined as the set room temperature T _S , respectively.

The operation switch SW is turned on (step s1).
Then, the control unit 9 puts the combustion fan 8 into an operating state (step s2). When the prepurge is completed (YES in step s3), the control unit 9 sets the igniter to the operating state (step s4).

In step s5, the control unit 9
Sets the solenoid valves 25 and 26 to the open state and the gas proportional valve 27 to the operating state, and proceeds to step s6. If ignition is detected in step s6 (YES), the process proceeds to step s7. In step s7, the control unit 9 activates the convection fan 3 and proceeds to step s8.

At step s8, the control unit 9 stops the operation of the igniter, and proceeds to step s9. Steps
9, the first combustion control means 6 of the control unit 9 controls the combustion fan 8 and the gas proportional valve 27 so that the required amount of combustion is obtained.
Is performed, and the process proceeds to step s10.

[0047] In step s10, the {if the detected room temperature T becomes the first reference temperature above T _1} If the detected room temperature T is in the set room temperature Ts + 0.33 ° C. or higher (YES), the step s11 Advance ｛Elapsed time 901, 902,
903, 904}. The detection room temperature T is equal to the set room temperature Ts +
If the temperature is less than 0.33 ° C. (NO), the process returns to step s9 to continue the proportional control.

At step s11, the second combustion control means 7 of the control unit 9 issues an instruction to temporarily stop the combustion of the combustor 2, and proceeds to step s12. As a result, the solenoid valves 25 and 26 are closed, the gas proportional valve 27 is stopped, and the combustion fan 8 is stopped. The operation of the convection fan 3 is continued until the end of the post purge (for 150 seconds).

It is determined in step s12 whether 150 seconds have elapsed since the combustion was stopped.
O) proceeds to step s13. If the time has elapsed (YES), the process proceeds to step s14.
907｝. In this case, the reference temperature change unit 72 of the second combustion control means 7, the second reference temperature T _2, to change the setting room temperature Ts + 0.33 ° C. from the setting room temperature Ts {= first reference temperature T _1}.

[0050] In step s13, the second combustion control means 7 of the control unit 9, detects room temperature T is set at room temperature Ts or less during post-purge {= a second reference temperature T ₂ less} discriminates whether or not has decreased to If it has not decreased (NO), the process returns to step s12, and if it has decreased (YES; elapsed time 905), the process returns to step s2 to restart the combustion of the combustor 2.

Since the post-purge has been completed, {circle over (9)}
06, 907 °, in step s14, the control unit 9 instructs the stop of the operation of the convection fan 3, and proceeds to step s15. In step s15, the second combustion control means 7 of the control unit 9, detects room temperature T is set at room temperature Ts + 0.33 ° C. or less determined whether decreased to {= first reference temperature T ₁ of less}, decreases If there is (YES; elapsed time point 906), the flow returns to step s2 to restart the combustion of the combustor 2.
If it has not decreased (NO; elapsed time point 907), an instruction is given to stand by while the convection fan 3 is stopped.

Next, advantages of the FF type gas hot air heater A of this embodiment will be described. When the convection fan 3 is stopped after the end of the 150-second post-purge, the room air 10 stops flowing to the room temperature sensor 4, so the detected room temperature T detected by the room temperature sensor 4 {shown by a solid line in FIG. It will be detected higher than {two-dot chain line in FIG. 4}.

However, at the end of the post-purge, the reference temperature changing section 72 sets the second reference temperature T ₂ ｛= set room temperature Ts｝.
, The second reference temperature T ₂ ｛during the post-purge = set room temperature T
s｝ first reference temperature T ₁ = set room temperature Ts + 0.
Since the temperature is changed to 33 ° C., the time when the actual room temperature drops to the temperature at which combustion should be restarted (elapsed time 908)
Thus, the combustion of the combustor 2 can be restarted. For this reason, since room temperature control is performed appropriately, the user does not feel cold. Further, since no cool air is blown out, the user does not feel uncomfortable.

The present invention includes the following embodiments in addition to the above embodiments. a. Instead of performing post-purging in which the convection fan 3 is continuously operated for a predetermined time, a configuration in which post-purging is performed until the in-machine temperature falls below a predetermined temperature may be employed. ).

B. In the above embodiment, the case where the second reference temperature is changed has been described. However, by correcting the temperature detected by the room temperature sensor 4 to be lower, an actual room temperature is predicted, and the corrected temperature and the second reference temperature are used. May be compared. Thus, the combustion can be restarted when the actual room temperature falls to the temperature at which the combustion should be restarted {corresponding to claims 4 and 5}.

C. The first combustion control means for switching the gas flow according to the load may not be provided. That is, the temperature control may be performed only by the second combustion control unit that switches between the combustion state and the stop state.

D. The present invention may be applied to a fan heater of a type in which room air and combustion air sucked from an air inlet are mixed and blown out as hot air. e. The fuel may be kerosene or the like other than gas, and the heating source may be an electric heater or the like. In addition, to the heating source,
“The combustor that is supplied with fuel and burns ｛heating amount (burning amount)
The effect is particularly excellent when the present invention is applied to a hot air heater that employs｝ ″, which is difficult to reduce to near zero.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an FF gas hot air heater according to one embodiment of the present invention.

FIG. 2 is a block diagram of the FF gas hot air heater.

FIG. 3 is a flowchart showing the operation of the FF gas hot air heater.

FIG. 4 shows the elapsed time in the FF gas hot air heater.
-It is a graph which shows the relationship of a temperature.

[Explanation of symbols]

A FF type gas hot air heater (hot air heater) 1 Housing 2 Combustor (Heating source) 3 Convection fan 4 Room temperature sensor 5 Room temperature setting device 7 Second combustion control means (Heating control means) 10 Indoor air 11 Suction port 12 air outlet 30 hot air 71 reference temperature determining unit 72 reference temperature change unit T detected room temperature T ₁ the first reference temperature T ₂ the second reference temperature Ts set room temperature

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-341714 (JP, A) JP-A-56-42047 (JP, A) JP-A-5-52541 (JP, U) (58) Field (Int.Cl. ⁶ , DB name) F24H 3/06 304 F23N 5/20 101 F24H 3/04 305 F23N 5/02 350

Claims (5)

(57) [Claims] 1. A housing having an inlet and an outlet, a heating source arranged in the housing, and indoor air sucked from the inlet, and the indoor air heated by the heating source is blown as warm air. A convection fan that blows out from an outlet, a room temperature sensor that is disposed near the suction port and detects room temperature, a room temperature setter that sets room temperature, and that based on the set room temperature, determines first and second reference temperatures. When the detected room temperature exceeds the first reference temperature, the operation of the heating source is temporarily stopped, and a post purge for continuously operating the convection fan for a predetermined time is provided. When the detected room temperature falls below the second reference temperature lower than the first reference temperature during the heating stop, a heating control means for restarting the operation of the heating source is provided. , Said heating control means, when the post-purge is completed,
A hot-air heater having a reference temperature change unit that changes the second reference temperature to a temperature higher than the second reference temperature during post-purge. 2. A housing having an inlet and an outlet, a heating source disposed in the housing, and indoor air sucked from the inlet, and the room air heated by the heating source is blown as warm air. A convection fan that blows out from an outlet, a room temperature sensor that is disposed near the suction port and detects room temperature, a room temperature setter that sets room temperature, and that based on the set room temperature, determines first and second reference temperatures. When the detected room temperature exceeds the first reference temperature, the operation of the heating source is temporarily stopped, and the convection is continued until the temperature in the machine falls below a predetermined temperature. A heating control means for performing post-purging for continuously operating the fan and restarting the operation of the heating source when the detected room temperature falls below a second reference temperature lower than the first reference temperature during the heating stop. In warm-air heating apparatus having a, the heating control means, when the post-purge is completed,
A hot-air heater having a reference temperature change unit that changes the second reference temperature to a temperature higher than the second reference temperature during post-purge. 3. The first reference temperature determined by the reference temperature determination unit is higher than a set room temperature set by the room temperature setting device, and the second reference temperature determined by the reference temperature determination unit is set by the room temperature setting. 3. The hot air heater according to claim 1, wherein the second reference temperature changed by the reference temperature changing unit is equal to the set room temperature set by the heater, and the second reference temperature is equal to the first reference temperature. 4. 4. A housing having an inlet and an outlet, a heating source disposed in the housing, and indoor air sucked from the inlet, and the indoor air heated by the heating source is blown as warm air. A convection fan that blows out from an outlet, a room temperature sensor that is disposed near the suction port and detects room temperature, a room temperature setter that sets room temperature, and that based on the set room temperature, determines first and second reference temperatures. When the detected room temperature exceeds the first reference temperature, the operation of the heating source is temporarily stopped, and a post purge for continuously operating the convection fan for a predetermined time is provided. When the detected room temperature falls below the second reference temperature lower than the first reference temperature during the heating stop, a heating control means for restarting the operation of the heating source is provided. , Said heating control means, when the post-purge is completed,
A hot-air heater, wherein the detected room temperature is corrected to a temperature lower than the temperature detected by the room temperature sensor, and the corrected room temperature is compared with the second reference temperature. 5. A housing having an inlet and an outlet, a heating source disposed in the housing, and indoor air sucked from the inlet, and the indoor air heated by the heating source is blown as warm air. A convection fan that blows out from an outlet, a room temperature sensor that is disposed near the suction port and detects room temperature, a room temperature setter that sets room temperature, and that based on the set room temperature, determines first and second reference temperatures. When the detected room temperature exceeds the first reference temperature, the operation of the heating source is temporarily stopped, and the convection is continued until the temperature in the machine falls below a predetermined temperature. A heating control means for performing post-purging for continuously operating the fan and restarting the operation of the heating source when the detected room temperature falls below a second reference temperature lower than the first reference temperature during the heating stop. In warm-air heating apparatus having a, the heating control means, when the post-purge is completed,
A hot-air heater, wherein the detected room temperature is corrected to a temperature lower than the temperature detected by the room temperature sensor, and the corrected room temperature is compared with the second reference temperature.