초록 ▼

The invention relates to a gas/air ratio control apparatus for a temperature control loop for household gas appliances, in particular for domestic/direct hot water units and combined direct hot water/central heating units, for temperature control of domestic and/or heating water. The invention is pa

The invention relates to a gas/air ratio control apparatus for a temperature control loop for household gas appliances, in particular for domestic/direct hot water units and combined direct hot water/central heating units, for temperature control of domestic and/or heating water. The invention is particularly suitable for household appliances up to 120 KW. The gas/air ratio control apparatus comprises a controllable fan (3) for supplying a predetermined air stream (2-2) to a burner (4) in dependence on the detected actual temperature (TActual) and the desired target temperature (TTarget) of the heating and/or domestic hot water; and a pressure-controllable valve (8) for controlling the supply of a specified fuel quantity (1) to the burner (4) in dependency exclusively on the absolute pressure of the air stream (2-2) produced by the controllable fan (3). The inventive temperature control apparatus operates in an air/fuel regulating range of 20% to 100%, the controllable valve (8) supplying a fuel quantity (1) to the burner (4) having a pressure at a ratio of 1:1 to the absolute pressure of the air stream (2-2) produced by the controllable fan (3). The system uses only one pressure sensing line (11) and can always be brought into a safe condition when faults appear in the burner (4).

대표청구항 ▼

Fuel/air ratio control apparatus for controlling operation of a burner of an appliance for heating water, said fuel/air ratio control apparatus comprising: a) a temperature measuring device for determining an actual temperature of water heated by the appliance and a controllable fan adapted to suppl

Fuel/air ratio control apparatus for controlling operation of a burner of an appliance for heating water, said fuel/air ratio control apparatus comprising: a) a temperature measuring device for determining an actual temperature of water heated by the appliance and a controllable fan adapted to supply a predetermined air stream that is related to the determined actual temperature of water heated by the appliance; b) an air supply line adapted to supply the air stream to the burner through a restriction arranged in the air supply line; c) a fuel supply line adapted to supply fuel to the burner through a nozzle, d) a pressure sensing line adapted to transfer the absolute pressure of the air stream produced by the controllable fan, and e) a pressure-controllable valve connected to the fuel supply line, said pressure-controllable valve including a main diaphragm separating first and second chambers that are sealed from each other, a main valve connected to said main diaphragm adapted to be movable to regulate fuel flow in the first chamber, and a control valve including a control diaphragm adapted to be externally controlled exclusively in response to the absolute pressure transferred by said pressure sensing line, wherein said control valve communicates with said second chamber to enable said main diaphragm to adjust the position of said main valve.