Gas water heater, control method and system thereof, storage medium and program product

The invention discloses a gas water heater and a control method and system thereof, a storage medium and a program product, and the control method of the gas water heater comprises the steps that in response to a starting instruction of a zero cold water mode, whether the water flow in a zero cold water circulation pipeline of the gas water heater is smaller than the preset starting flow or not is judged; under the condition that the water flow is smaller than the starting flow, the combustion load adjusting amount is calculated according to the starting flow, the water flow and a preset combustion load, and the actual combustion load is calculated according to the preset combustion load and the combustion load adjusting amount; and controlling a combustor of the gas water heater to heat water in the zero cold water circulation pipeline according to the actual combustion load, so that the gas water heater can work normally, the situation that the water temperature in the pipeline is too high, and a user is sc