Heat pump water heater

Abstract

The invention relates to a heat pump water heater and belongs to the technical field of water heaters. The water heater comprises a heat pump system which consists of a compressor, a condenser, a throttling element, and an evaporator. The condenser is arranged on a water tank of the water heater to form a heat exchange structure; and the condenser consists of at least two sections of heat exchange tubes which are connected in series along the flow direction of a refrigerant, and the flow area of the front section of the heat exchange tube is more than that of the rear section of the heat exchange tube. Because the heat exchange capacity of the condenser is effectively improved, the heat pump performance can be effectively improved when the heat exchange area is the same; the heat exchange area and weight needed by the condenser are greatly reduced on the premise of guaranteeing good operating effect of the heat pump; the materials and processing cost thereof are effectively saved; and the structural dimension is reduced. Therefore, the reliability is improved; and due to the simpleness and practicality of the structure and technology, the cost is reduced, and the market competitiveness of the products is improved.

Description

technical field [0001] The invention relates to a heat pump water heater, in particular to an improved heat exchanger structure of the heat pump water heater, and belongs to the technical field of water heaters. Background technique [0002] Heat pump water heaters have a good energy-saving effect, so they have developed rapidly in recent years. In the static heating units widely used in small-capacity heat pump water heaters, the fluorine water heat exchanger is usually placed inside the hot water tank, and the high-temperature refrigerant steam passes through the exchange in the tube. The heat pipe heats the water body outside the pipe to the required temperature, and some products also use the condensing heat exchange pipe to wrap around the outer wall of the hot water tank to solve the corrosion problem of the built-in heat exchanger. At the same time, the fluorine water heat exchangers used in the existing heat pump water heaters are all built-in or externally wound flu...

AI Technical Summary

Problems solved by technology

At the same time, the fluorine water heat exchangers used in the existing heat pump water heaters are all built-in or externally wound fluorine water heat exchangers with equal pipe diameters, and their heat transfer capacity is low

The reason is mainly because condensation heat transfer is a complex two-phase flow heat transfer. As the condensate increases, the liquid film between the wet steam and the tube wall gradually thickens, which becomes the main obstacle to heat exchange, resulting in condensation. Decreased heat transfer capacity

Moreover, this type of heat exchanger consumes a lot of materials, high cost, heavy weight, and takes up a lot of space. It is prone to reliability problems due to various corrosion and stress concentration.

Many manufacturers have to choose smaller heat exchangers in order to save costs, resulting in a reduction in the heating capacity of the heat pump and its energy efficiency ratio (COP)

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