Overview

Often used for low temperature heat source heat pump is around us media-air, water, sea water, wastewater, surface water, groundwater, water, fire, or from the emission of refrigerant in industrial production equipment, these refrigerants are often associated with the media around with similar temperatures. Principle of heat pump and compression-type refrigerating machine is consistent, small air conditioners, in order to give full play to its effectiveness, air conditioning in summer cooling or heating in winter, is done using the same equipment. Winter, the air conditioner in the evaporator and condenser replacement through a valve, as described in [2].

In summer air conditioning cooling Shi, by refrigeration workers condition run, by compressor discharge of high pressure steam, by reversing valve (and said four pass valve) into condensation device; in winter heating Shi, first will reversing valve steering hot pump work location, so by compressor discharge of high pressure refrigeration agent steam, by reversing valve Hou into indoor evaporator (for condensation used), refrigeration agent steam condensation Shi released of latent heat, will indoor air heating, reached indoor heating purpose, condensation Hou of liquid refrigeration agent, from reverse through throttle device into condensation device (for evaporator with) , Absorb heat and evaporation, evaporation of steam passes through the reversing valve compressor suction, complete heating cycle. In this way, the outside air (or water) heat in "pump" into the hot Interior, it is called "heat pump". Shanghai refrigerator factory CKT-13 a window air conditioner, is a heat pump type air conditioner.

In the heat pump cycle, from low temperature heat source (outdoor air or water, whose temperature is higher than the evaporation temperature t0) made in Q0kcal/h heat, mechanical power is consumed ALkcal/h, high-temperature heat source (indoorheating systems) Q1kcal/h supply of heat, which is consistent with the relationship between the first law of thermodynamics, namely Q1=Q0+ALkcal/h

Without heat pumps, and mechanical work into heat (or electricity to heat the hot reservoir, the proceeds of the heat for the ALkcal/h, after using heat pumps, high-temperature heat source (heating system) more heat: Q1-AL=Q0,kcal/h

This heat is taken from a low temperature heat source without heat pumps, you cannot make this heat. It aims to save fuel with a heat pump device, and using waste heat.

Heat pump duty cycle and engine operating cycle, the opposite, engine is the use ofhigh-temperature heat energy to mechanical work, is by consuming mechanical work and heat pump in heat transfer of the heat to the hot object.

If heat pump and thermal machines are two identical heat, engine thermal efficiencyη =AL ╱ Q1; engine indicators of energy----heat transfer coefficient φ =Q1 logistics/AL, so φ = 1 on/η. Η is always less than 1, so φ is greater than 1. Chiller and heat pumps have two identical heat source temperature, and the relationship between them is: φ =Q1 logistics/AL= (Q0+AL)/tr AL= ε +1, ε is the refrigerator the coefficient. This can be seen, the minimum value of the heat transfer coefficient is ε = 1, this limitof Q0=0, that is, not draw heat from the cold reservoir. [1]

The basic principle

The principle of heat pump water heaters: it is mainly composed of compressors, heat exchangers, axial flow fans, holding tanks, pumps, tanks, filters, electronic expansion valve and electronic automatic controller and other components. Connected power Hou, axis flow fan began running, outdoor air through evaporator for hot Exchange, temperature reduced Hou of air was fan discharge system, while, evaporator internal of workers quality endothermic vaporization was inhalation compressor, compressor will this low voltage workers quality gas compression into high temperature, and high pressure gas into condensation device, was pump forced cycle of water also through condensation device, was workers quality heating Hou sent to for user using, and workers quality was cooling into liquid, the liquid by expansion valve throttle cooling Hou again into evaporator, so repeatedly cycle work, Thermal energy in the air is constantly "pump" sent into the water, the water temperature in the tank insulation increases, finally reaches 55 degrees Celsius, just right for people to take a bath, which is the basic principle of air-source heat pump water heater.

As Shang figure by shows, compressor outlet for high temperature high pressure gas, by condensation device for hot into high pressure low temperature steam liquid mixture, lost of heat by hot away for user heating, by storage liquid tank and expansion valve into low voltage low temperature gas into evaporator evaporation endothermic, absorption outside low grade of heat (can is rivers, and Lake, and groundwater, and underground soil layer, and air, that we by said of water, and to source, and air source hot pump), last evaporator out of low voltage gas into compressor completed cycle.

Heat pump heating principle

Evolution of heat pump water heaters are products, electromagnetic four-way valvein the refrigeration system load (also known as the reversing valve), through the four-way valve switches direction, changing the direction of the flow of refrigerant andair conditioners can be heated. Compressor from the refrigerant flow to the tank insulation of high temperature and high pressure steam-condenser, heat pass throughthe water of the water tank, and then through the expansion valve throttle in outdoor heat pump evaporator in the heat of the primary group, absorbs heat from the outdoor air quality. Heat pump water heater is absorbs heat from the outdoor air andtap water passes into the tank insulation, than electric heaters heating can save electricity, rapid, safe, and an outdoor thermal energy potential is infinite.

Heat pump Refrigeration principle

In summer air conditioning cooling Shi, by refrigeration workers condition run, by compressor discharge of high pressure steam, by reversing valve (and said four pass valve) into condensation device, refrigeration agent steam was condensation into liquid, by throttle device into evaporator, and in evaporator in the endothermic, will indoor air cooling, evaporation Hou of refrigeration agent steam, by reversing valve Hou was compressor inhalation, such cycle, achieved refrigeration cycle.

Air-source heat pump

Air-source heat pump cooling unit is a used air as cooling (heating) sources of indoor space, air conditioning, heating and domestic hot water function of air conditioning and water heater equipment.

Air-source heat pump cooling unit consists of five modes of operation. Summer running cooling and refrigerating mode of heating water; winter operation heating water heating and heating mode; excessive season can run hot water mode separately,so as to realize the whole living environment to provide cooling, dehumidifying, heating and domestic hot water. When operating in refrigeration and heating water, total heat recovery can be achieved, bi-directional energy efficiency ratio total more than 7.0, hot water is free.