JPH0512676Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Industrial application field] This invention is applicable to combustors, heat exchangers, convection blowers,
and a hot air heater having a filter.

[Conventional technology]

In a structure in which a hot water heat exchanger and a blower are provided inside a main body casing having an inlet and an outlet for indoor air, a hot water temperature detector is provided at the hot water inlet of the hot water heat exchanger, and the detection of this detector is performed. A hot water radiator for indoor heating has been proposed which is provided with a controller that inputs an output and controls the rotation speed of the blower (for example, Japanese Utility Model Application No. 41726/1983).

In addition, an air conditioner has been proposed that detects the inlet air temperature and outlet air temperature or piping temperature of the indoor heat exchanger, and detects filter clogging when the temperature difference exceeds an allowable level ( For example, Utility Model Publication No. 56-75655).

[Problem that the invention attempts to solve]

However, with such conventional devices, the former simply controls the rotation speed of the blower and cannot deal with abnormal situations, and the latter requires the use of two temperature detectors to detect filter clogging. There were problems such as lower reliability of the temperature detector.

This idea is intended to solve the above problems, and it detects filter clogging with one heat exchanger temperature detector, and also detects failure of the heat exchanger temperature detector and stops the combustor. The purpose is to provide a warm air heater that can be operated safely.

[Means for solving problems]

The hot air heater of this invention includes a combustor installed inside the heater body, a heat exchanger connected to the combustor, and air that is sent to the heat exchanger to heat it and blow hot air into the room. a convection blower, a filter provided on the blowing side of the convection blower, an indoor temperature detector for detecting indoor temperature, a heat exchanger temperature detector for detecting the temperature of the heat exchanger, and a filter provided on the blowing side of the convection blower; The combustion amount of the combustor is controlled to keep the indoor temperature almost constant according to the output of the temperature detector, and the operating temperature of the heat exchanger is kept almost constant according to the output of the heat exchanger temperature detector. In addition, when the temperature of the heat exchanger exceeds a first set temperature higher than the operating temperature, a filter clogging alarm is issued and combustion in the combustor is stopped. , and when the temperature of the heat exchanger does not reach a second set temperature lower than the operating temperature even after a certain period of time has elapsed after the start of combustion, a failure alarm of the heat exchanger temperature detector is issued to stop combustion in the combustor. A control circuit for stopping the operation is provided.

[Effect]

In the hot air heater of this invention, fuel such as oil or gas is supplied to a combustor installed in the heater body and burned, and air is supplied to a heat exchanger connected to the combustor using a convection blower. It heats up and blows warm air into the room. At this time, air is taken in through a filter installed on the suction side of the convection blower, and an indoor temperature sensor detects the indoor temperature, a heat exchanger temperature sensor detects the heat exchanger temperature, and each control is performed. input to the circuit. The control circuit controls the combustion amount of the combustor to keep the indoor temperature almost constant based on the output of the indoor temperature sensor, and keeps the operating temperature of the heat exchanger almost constant based on the output of the heat exchanger temperature sensor. The rotational speed of the convection blower is controlled to keep it constant, and when the temperature of the heat exchanger exceeds a first set temperature higher than the operating temperature, a filter clogging alarm is issued and combustion in the combustor is stopped. Further, when the temperature of the heat exchanger does not reach a second set temperature lower than the operating temperature even after a certain period of time has elapsed after the start of combustion, a failure alarm of the heat exchanger temperature detector is issued and combustion in the combustor is stopped. . The filter clogging alarm also serves as a short circuit alarm for the heat exchanger temperature detector.
In this way, a single heat exchanger temperature detector can detect filter clogging and also detect failures due to short circuits and disconnections in the heat exchanger temperature detector, thereby stopping the combustor and ensuring safe operation. I can do it.

〔Example〕

The figure is a block diagram showing a hot air heater according to an embodiment of this invention. In the figure, 1 is the main body of the heater, 2 is a combustor installed in this main body, 3 is a heat exchanger connected to this combustor, and 4 is air that is heated by sending air to this heat exchanger from an air outlet 5. A convection blower blows warm air into the room 6, 7 is a filter provided on the suction side of this convection blower, 8 is a heat exchanger temperature detector (thermistor) that detects the temperature of the heat exchanger 3, It is connected to the control circuit 9 so as to input a temperature signal. Reference numeral 10 denotes an indoor temperature detector, which is connected to detect the temperature in the room 6 and input a temperature signal to the control circuit 9. The control circuit 9 controls the combustion amount of the combustor 2 to keep the temperature in the room 6 constant based on the temperature signal from the indoor temperature detector 10, and controls the amount of combustion in the combustor 2 based on the temperature signal from the heat exchanger temperature detector 8. Vessel 3
The rotation speed of the convection blower 4 is controlled so as to keep the operating temperature of the heat exchanger 4 substantially constant, and when the temperature of the heat exchanger 3 exceeds a first set temperature higher than the operating temperature, a clogging alarm of the filter 7 is issued. Take out the combustor 2
When the combustion of the heat exchanger 3 is stopped and the temperature of the heat exchanger 3 does not reach the second set temperature lower than the operating temperature even after a certain period of time has passed after the start of combustion, a failure alarm of the temperature detector 8 is issued and the combustor 2 is configured to stop combustion.

In the warm air heater configured as described above, fuel such as oil or gas is supplied to the combustor 2 provided in the heater body 1 and burned.
Air is sent by a convection blower 4 to a heat exchanger 3 connected to a heat exchanger 3, heated from an outlet 5, and hot air is blown into a room 6. At this time, air is taken in through a filter 7 provided on the suction side of the convection blower 4, the temperature of the heat exchanger 3 is detected by a temperature detector 8, and the temperature of the room 6 is detected by an indoor temperature detector 10. , are input to the control circuit 9, respectively. Control circuit 9
controls the amount of combustion in the combustor 2 to keep the temperature in the room 6 constant based on the output of the room temperature detector 10. In addition, the control circuit 9 controls the rotation speed of the convection blower 4 to keep the operating temperature of the heat exchanger 3 almost constant based on the output of the heat exchanger temperature detector 8, and also controls the temperature of the heat exchanger 3. When the temperature exceeds the first set temperature, which is higher than the operating temperature, a clogging alarm of the filter 7 is issued and combustion in the combustor 2 is stopped. When the second set temperature, which is lower than the operating temperature, is not reached, the temperature detector 8 issues a failure alarm and combustion in the combustor 2 is stopped.

That is, when the filter 7 becomes clogged, even if the convection blower 4 rotates at a predetermined number of rotations, the air volume decreases and the temperature of the heat exchanger 3 increases. Therefore, the temperature detector 8 for controlling the rotation speed of the convection blower 4 can also serve as a detector for clogging of the filter 7. Furthermore, the thermistor that makes up the temperature detector 8 has a characteristic that its resistance value decreases as the temperature rises, so if the temperature detector 8 is disconnected, it will output that the temperature is low even if the temperature rises. . In this case, if the temperature detector 8 is disconnected, it means that the temperature is low as seen from the control circuit 9 side, so the rotation speed of the convection blower 4 is controlled low, and combustion continues in this state. This may cause the heat exchanger 3 to overheat, but if the temperature detector 8 does not detect the second set temperature lower than the operating temperature even after a certain period of time has passed after the start of combustion, the combustion is stopped. , overheating of the heat exchanger 3 is prevented.

The clogging alarm of the filter 7 is detected by the temperature detector 8.
Since it is also emitted when the temperature sensor 8 is short-circuited, it also serves as a short-circuit alarm for the temperature detector 8. In this way, one temperature detector 8 can detect clogging of the filter 7, and can also detect failures due to short circuits and disconnections in the temperature detector 8, thereby making it possible to stop the combustor 2 and perform safe operation. can.

In the above description, the specific circuit configuration of the control circuit 9 can be arbitrarily selected. Further, the structure of the heater main body 1 and the arrangement of each component are not limited to those shown in the drawings, but can be changed.

[Effect of idea]

According to the present invention, the combustion amount of the combustor is controlled to keep the indoor temperature almost constant based on the output of the indoor temperature sensor, and the operating temperature of the heat exchanger is controlled based on the output of the heat exchanger temperature detector. Since the rotational speed of the convection blower is controlled to keep the temperature approximately constant, if the temperature of the heat exchanger exceeds the first set temperature, which is higher than the operating temperature, it can be determined that the filter is clogged. , This makes it possible to issue an alarm and stop combustion in the combustor. Further, if the temperature of the heat exchanger does not reach the second set temperature lower than the operating temperature even after a certain period of time has passed after the start of combustion, it can be determined that the heat exchanger temperature detector has failed. It is possible to issue an alarm and stop combustion in the combustor.

For this reason, one room temperature detector and one heat exchanger temperature detector detect filter clogging and failure of the heat exchanger temperature detector, thereby stopping the combustor and ensuring safe operation. It can be carried out.

[Brief explanation of the drawing]

The figure is a block diagram showing one embodiment of this invention. 1... Heater body, 2... Combustor, 3... Heat exchanger, 4... Convection blower, 7... Filter, 8
... Heat exchanger temperature detector, 9 ... Control circuit, 10
...Indoor temperature detector.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A combustor installed in the main body of the heater, a heat exchanger connected to the combustor, and a system that heats air by sending air to the heat exchanger and blows hot air into the room. a convection blower that blows out, a filter provided on the blowing side of the convection blower, an indoor temperature detector that detects the indoor temperature, and a heat exchanger temperature detector that detects the temperature of the heat exchanger; The combustion amount of the combustor is controlled to keep the indoor temperature approximately constant based on the output of the indoor temperature sensor, and the operating temperature of the heat exchanger is controlled approximately based on the output of the heat exchanger temperature sensor. The rotation speed of the convection blower is controlled to be kept constant, and when the temperature of the heat exchanger exceeds a first set temperature higher than the operating temperature, a filter clogging alarm is issued to stop combustion in the combustor. A second heat exchanger in which the temperature of the heat exchanger is lower than the operating temperature even when the combustion is stopped and a certain period of time has elapsed after the start of combustion.
A hot air heater comprising: a control circuit that issues a failure alarm for a heat exchanger temperature detector and stops combustion in a combustor when the set temperature of the heat exchanger is not reached. (2) The hot air heater according to claim 1, wherein the filter clogging alarm also serves as a temperature detector short circuit alarm.