Forced flue heater

Patent metadata

Field	Value
Publication number	US-10041699-B2
Application number	US-201615000073-A
Country	US
Kind code	B2
Filing date	Jan 19, 2016
Priority date	Feb 4, 2015
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

A forced flue heater draws out combustion gas using a burner fan installed downstream from a heat exchanger to prevent a burner fan motor from being heated to high temperature. The forced flue heater blows air to an air channel using a blower fan, and warms the air using the heat exchanger contained in the air channel. The pressure upstream from the heat exchanger is higher by a value corresponding to the resistance of the heat exchanger. The blower fan contained in an outer case draws in the surrounding air to lower the pressure inside the outer case. A partition separating between the inside and the outside of the air channel has an air outlet located upstream from the heat exchanger. This allows the cool air upstream from the heat exchanger to flow outside the partition. The air is then used as cooling air for cooling the burner fan motor. This structure prevents the burner fan motor from being heated to high temperature when the burner fan is heated to high temperature.

First claim

The invention claimed is:

1. A forced flue heater, comprising:
an outer case having an air inlet and a warm air outlet;
a blower fan contained in the outer case, the blower fan being rotatable to draw air into the outer case through the air inlet;
a heat exchanger configured to warm the air drawn in the outer case to allow the blower fan to blow the warmed air through the warm air outlet;
an air channel including a partition defining the channel inside the outer case, the air channel containing the heat exchanger, the air channel having a first end that is open toward the blower fan and a second end that is open toward the warm air outlet to guide air blown from the blower fan toward the warm air outlet;
a burner configured to burn fuel to generate combustion gas and supply the combustion gas to the heat exchanger;
a burner fan configured to draw the combustion gas out of the heat exchanger to draw fresh air into the burner;
a burner fan motor arranged outside the air channel to drive the burner fan; and
an air filter disposed at the air inlet and passing air that has flowed into the outer case,
wherein the blower fan is disposed at the first end of the air channel and draws air from the outer case into the air channel;
wherein the partition of the air channel includes an air outlet located upstream from the heat exchanger; and
wherein actuation of the blower fan generates a difference in pressure between an inside and an outside of the partition, such that the difference in pressure causes air upstream from the heat exchanger to flow through the air outlet to cool the burner fan motor.

2. The forced flue heater according to claim 1 , further comprising:
a guide channel located outside a portion of the partition including the air outlet, the guide channel being configured to guide cooling air flowing through the air outlet toward the burner fan motor.

3. The forced flue heater according to claim 2 ,
wherein the air outlet is open in a direction to receive air from the blower fan.

4. The forced flue heater according to claim 1 ,
wherein the air outlet is open in a direction to receive air from the blower fan.

5. The forced flue heater according to claim 1 ,
wherein the heat exchanger comprises
an combustion gas inlet through which the combustion gas flows into the heat exchanger, and
an combustion gas outlet through which the combustion gas flows out of the heat exchanger;

wherein, in air flow inside the air channel, the combustion gas outlet is disposed at a downstream side of the combustion gas inlet;
wherein, in the air flow inside the air channel, the burner fan is disposed at an upperstream side of the combustion gas outlet;
wherein an connector channel is configured to guide the combustion gas flowing out of the heat exchanger to the burner fan; and
wherein the connector channel is configured, such that the combustion gas inside the connector channel flows toward an opposite direction to a direction of the air flow inside the air channel.

6. The forced flue heater according to claim 5 , further comprising:
a guide channel located outside a portion of the partition including the air outlet, the guide channel being configured to guide cooling air flowing through the air outlet toward the burner fan motor.

7. The forced flue heater according to claim 5 ,
wherein the air outlet is open in a direction to receive air from the blower fan.

8. The forced flue heater according to claim 6 ,
wherein the air outlet is open in a direction to receive air from the blower fan.

Assignees

• Rinnai Kk

Inventors

• Iwama Takahiro
• Kawamura Yoshiaki

Classifications

• F24H3/087 Primary

  using fluid fuel · CPC title

• F24H9/1881

  using fluid fuel · CPC title

• F24H9/0073

  Arrangement or mounting of means for forcing the circulation of air · CPC title