Solution and Improvement of Common Faults of Air Source Heat Pump Compressor

Air source heat pump system in the hot water, heating, drying and other fields are widely used, which is characterized by most of the heat from the air in the low-temperature heat energy, so more prominent in energy conservation, in line with the concept of environmental protection. However, most of the air source heat pump units are installed outdoors. Due to the influence of the external environment, the working range fluctuates greatly. The unit runs for a long time under non-standard conditions. Under some severe conditions, the air heat pump units may appear Some compressor fault problem. The importance of heat pump compressor is self-evident, is the whole air heat pump system, "engine", equivalent to the human heart.

Air-source heat pump units used in many types of heat pump compressors to fully enclosed piston compressor is common, and fully enclosed piston compressor failure problems, mostly occurred in winter heating operation. Through the failure of some fault compressor anatomical observation of the situation, the heat pump compressor can be roughly divided into three categories:

1. Heat pump compressor suction and exhaust valve rupture

Phenomenon: Compressor oil level is normal, compressor bearings, crankshaft, connecting rod intact, suction and exhaust valve rupture.

2. Heat pump compressor stall (such failures more)

Phenomenon: compressor oil is black, the upper and lower bearing sleeve off or wear, connecting rod fracture, the crankshaft and bearing friction surface and crankshaft and connecting rod friction surface with traces of wear, the motor rotor wear marks, suction and exhaust valve intact.

3. Heat pump compressor motor burned

Phenomenon: Compressor insulation to 0, the compressor bearings, crankshaft, connecting rod intact

For the above reasons for heat pump compressor analysis, to give the appropriate improvements:

a. Control should have antifreeze control function (that is, in the shutdown state, when the ambient temperature is below a certain value, the pump or electric heating should be put into operation to prevent freezing of the water system), while the water system should be equipped with drainage devices When the unit leader does not use time, should drain the water inside the water exchanger to prevent freezing damage.

b. In order to ensure the normal operation of the unit, the flow switch and various protection switches can not be short-circuited by themselves; when the unit is running, it is necessary to observe frequently and find out when the temperature difference between the inlet and outlet of the unit is too large, check the water system in time: Is it normal, water flow and water filter cleaning.

c. Add the conditions in the electronic control program to ensure the heating time of the compressed crankcase heater before starting to ensure that the compressor can fully preheat to prevent damage.

d. Improve the defrost method to ensure timely defrosting and defrosting thorough, improve the reliability of electronic control, prevent misoperation or non-action.

e. Improve the system design, especially in the low-temperature heating conditions, the expansion valve and gas-liquid separator should be reasonable to match, or to increase the high pressure and low pressure bypass and other measures to prevent the unit back to the liquid problem.

f. Improve the process, strengthen the management and enhance the awareness of quality, to ensure that the refrigeration system clean and dry, no water, manufacturing and processing quality is an important factor affecting the quality of the unit, many problems must be preventive measures to avoid causing major problems.

g. Enhance the user's use, operation and maintenance training.