Heat exchanger, fully premixed hot water boiler and control method thereof

Abstract

The invention provides a heat exchanger. The heat exchanger comprises a front heat exchange part, a rear heat exchange part and at least one middle heat exchange part located between the front heat exchange part and the rear heat exchange part. The upper portion of each heat exchange part is provided with a radiation cavity, and the multiple radiation cavities are connected in a through manner to form a combustion chamber of the heat exchanger. Each heat exchange part is provided with a water outlet, a water inlet and water channel interlayers, and the multiple water channel interlayers of each heat exchange part are arranged in a staggered manner so as to form a heat exchange water channel. The heat exchange water channel of each heat exchange part comprises a first heat exchange water channel body and a second heat exchange water channel body which communicate with the corresponding water outlet and the corresponding water inlet. Each second heat exchange water channel body is arranged completely around the corresponding radiation cavity. According to the heat exchanger, the heat exchange efficiency can be effectively improved, no refractory matter is needed for heat insulation, and the service life is prolonged. The invention further provides a full premixing hot water boiler and a control method thereof.

Description

technical field [0001] The invention relates to the technical field of heat exchange, in particular to a heat exchanger, a fully premixed hot water boiler and a control method thereof. Background technique [0002] In the prior art, the gas-fired boiler transfers heat to the cold water flowing through the heat exchanger through gas combustion heating to achieve the purpose of preparing hot water. The gas boiler is mainly composed of a burner and a heat exchanger. The burner needs to burn gas in the combustion chamber in the heat exchanger to heat the cold water in the heat exchanger to obtain hot water. [0003] The temperature of the heat exchanger can be as high as 1200°C, and the heat exchanger has some structural defects due to the casting aluminum process. The heat exchanger has a local high-temperature area where the water flow is blocked and heat exchange cannot be performed, especially in some areas around the combustion chamber. Full water-cooled heat exchange cann...

AI Technical Summary

Problems solved by technology

However, before ignition and combustion, the heat exchanger is generally in the cold stage and low thermal stress stage. If it enters the PID control stage immediately after ignition and combustion (following up the target outlet water temperature and the actual outlet water temperature to adjust), the burner will use high power When working, the temperature of the furnace will rise rapidly, which will cause a very large thermal stress impact on the heat exchanger, and even the water flow cannot keep up with it, resulting in dry burning, which is not conducive to the long-term use of the heat exchanger and the operation safety of the gas boiler

Images