초록 ▼

A control circuit for a heating system having a gas burner assembly, a heat absorbing coil, a heat releasing coil, a circulating pump for pumping a hydronic fluid between the two coils, and an air blower for the heat releasing coil is disclosed. The control circuit includes a thermostat located in t

A control circuit for a heating system having a gas burner assembly, a heat absorbing coil, a heat releasing coil, a circulating pump for pumping a hydronic fluid between the two coils, and an air blower for the heat releasing coil is disclosed. The control circuit includes a thermostat located in the space to be heated and a first relay switch which electrically connects the circulating pump in response to a signal from the thermostat. A combustion safety control is electrically connected to the thermostat, a main gas valve, and a flame sensor such that the main gas valve is open in response to a signal from the thermostat and the main gas valve is closed where no signal is received from the thermostat or an insufficient signal is received from the flame sensor. A second relay switch is electrically connected to the air blower, the circulating pump, and a hydronic fluid temperature sensor such that in response to a signal from the fluid temperature sensor the air blower and the circulating pump are electrically connected. After the thermostat ceases to send a signal to the first relay switch, the second relay switch acts to electrically connect the air blower and the circulating pump so long as the temperature of the fluid is sufficient to provide heat to the space to be heated. A number of safety features are also provided.

대표청구항 ▼

A control circuit for a heating system having a compartment in which a gas burner assembly and a heat absorbing coil are disposed, the burner assembly including an ignitor and a main gas valve, the heating system further having a heat releasing coil disposed in an enclosure in a space to be heated,

A control circuit for a heating system having a compartment in which a gas burner assembly and a heat absorbing coil are disposed, the burner assembly including an ignitor and a main gas valve, the heating system further having a heat releasing coil disposed in an enclosure in a space to be heated, a circulating pump means for pumping a hydronic fluid between the two coils, and an air blower means for blowing air over the heat releasing coil and into the space to be heated; said control circuit comprising: a thermostat means located in the space to be heated for supplying an electrical signal in response to the need for heat in the space to be heated; a first switch means for energizing the circulating pump means in response to a signal from said thermostat means; a flame sensor means located in the gas burner assembly for providing a signal in response to the presence of a flame; a combustion safety control means electrically connected to said thermostat means, the main gas valve, and said flame sensor means for supplying a signal to open the main gas valve in response to the signal from the thermostat means, and for supplying a signal to close the main gas valve when a signal of less than a selected level is received from said flame sensor or no signal is received from said thermostat means; a hydronic fluid temperature sensor means for producing an electrical signal in response to the hydronic fluid exceeding a minimum temperature level; a second switch means for energizing the air blower means and the circulating pump means in response to the signal from said hydronic fluid temperature sensor means such that, after the signal from said thermostat means ceases and said first switch means no longer provides energization of the circulating pump means, said second switch means continues to provide energization to the circulating pump means and the air blower means so long as a signal is received from said fluid temperature sensor means.