Patent ID: 9568213
Date: 2017-02-14
CPC Classifications: F23C,F24H

Claim:
1. A storage gas water heater comprising a water tank, a fan, a partial premix burner and a heat exchanger and combustion tube, wherein: an air inlet of the fan is open to air outside of the water heater and an outlet of the fan is connected with an air-supply opening; the air-supply opening is connected with the partial premix burner by a first air-supply channel and is connected with a combustion chamber of the heat exchanger and combustion tube by a second air-supply channel; the first and second air-supply channels together define a totally-sealed channel from the air inlet of the fan to the heat exchanger and combustion tube; at least part of the heat exchanger and combustion tube is inside the water tank; one end of the heat exchanger and combustion tube is connected with an outlet of the partial premix burner and an opposite end is open to air outside of the water heater; an excess air ratio for combustion in the combustion chamber is less than 1.5; the partial premix burner is composed of a plurality of harmonica-like burners and receives all primary and secondary air for combustion from the fan through the totally-sealed channel defined by the first and second air-supply channels; and the second air-supply channel connects a secondary air distributing plate, located between the air-supply opening and the combustion chamber, to the combustion chamber through at least one gap between the plurality of harmonica-like burners.