Air Conditioning Unit Forced Oil Return Method

Abstract

The invention relates to an enforcing oil-returning method of an air-conditioning unit and particularly relates to an enforcing oil-returning method during the maintenance of the air-conditioning unit which is in abnormal operation. By the aid of the enforcing action of an oil pump, refrigeration oil retained on air-conditioning system parts such as evaporators is returned to a compressor. The method comprises steps of determining whether a device lacks oil; detecting whether the oil quality in the unit meets the standard and determining that the oil is enforced to return or refrigeration oil is replaced; connecting pipelines, discharging the air in pipelines and starting the oil pump to return the oil; completely detecting whether other parts of the device are normal; and commissioning. The method is applied to maintenance of unit devices such as air-conditioning units, air-conditioning heat pump units, refrigerator refrigerating units and ice making machines.

Description

technical field [0001] The invention relates to a method for forced oil return of an air conditioner unit, especially the method for forced oil return during maintenance of an air conditioner unit due to abnormal operation. Background technique [0002] As we all know, lubricating oil in machinery and equipment mainly has the function of cooling and lubricating moving parts. The refrigerating oil in air-conditioning units is a typical lubricating oil. The compressor discharges into the condenser, then through the expansion valve and into the evaporator, and from the evaporator back to the compressor. In the whole system, the evaporator is generally the part with relatively low pressure and temperature, and the viscosity of the refrigerating oil is the highest, so it is difficult to return the oil. If there is too much refrigerating oil in the evaporator and other parts, serious It hinders the heat exchange of the evaporator, seriously affects the normal operation of the equ...

AI Technical Summary

Problems solved by technology

[0003] The problem of oil return in flooded central air-conditioning units is more prominent. The flooded central air-conditioning unit has a large amount of refrigerant in the evaporator, and the accumulated refrigerant oil is much more than that in dry-type evaporators. Generally, it is equipped with ejector oil return The device ensures that the system is not short of oil, but since the position of the oil tank of the ejection oil return device is basically fixed, when the system is not working properly, and the refrigerant liquid level in the evaporator is not properly controlled, a large amount of refrigerated oil will accumulate in the The condition of the evaporator and other parts will cause the compressor to be seriously short of oil and cause an alarm, and the system will not work

[0004] When encountering a compressor oil shortage failure, the unit cannot be started due to the oil level alarm of the compressor. There are two common methods. The first method is to short-circuit the oil level alarm controller to force the compressor to run. Pump the refrigerating oil back to the compressor when the machine is running. This operation requires high technical requirements and is not effective every time. Once it fails, the compressor may be damaged due to lack of oil; another method is more commonly used, directly to the Add new refrigerating oil to the compressor, and then turn it on. In this case, the total amount of refrigerating oil in the entire system will be too much, the heat exchange performance of the unit will deteriorate, and the power consumption will increase.