If the TEC EVAPORATOR has a fault and needs to be diagnosed, it first needs to be suppressed and checked for leaks. The process of suppressing leaks can be divided into the following three steps: ①Tighten the total pressure to see if there is leakage in the refrigeration pipeline; ②Connect the high and low pressure sections to suppress the pressure, mainly to verify whether the low pressure pipeline (ie, the evaporator) Leakage exists; ③Suppress the low pressure section by section, and then determine the leakage position of the upper and lower TEC EVAPORATOR. The method of suppressing varies depending on the type of evaporator. The evaporator in the freezer compartment of a refrigerator can generally be divided into two types, the built-in type and the exposed type, which can also be called the drawer type. The fault diagnosis method is as follows:
1. The fault diagnosis method of the built-in TEC EVAPORATOR
For the built-in TEC EVAPORATOR, you can judge whether the evaporator is good or bad only by hitting the low pressure to see if there is any leakage in the low pressure pipeline. The specific diagnosis steps are as follows:
1) First cut open with a pipe cutter, look at the process tube at the upper end of the compressor process nozzle, and then deflate the refrigeration pipeline.
Next, open the welding port between the return pipe of the evaporator and the suction pipe of the compressor, and then weld the welding port between the capillary tube and the filter drier, and seal the end of the capillary tube with gas welding.
2) At the mouth of the TEC EVAPORATOR return pipe, a vacuum pressure gauge needs to be welded, and then a nitrogen cylinder is used to pass the vacuum pressure gauge to suppress the low-pressure refrigeration pipeline (generally, the pressure is usually 0.78MPu), the most common Method Use soapy water to check the welding points of the vacuum pressure gauge, the return pipe and the capillary end to confirm whether there is any leakage. After confirming that there is no leakage, observe for 24h. If the reading of the vacuum pressure gauge does not change. For an evaporator with good performance, the vacuum pressure gauge reading should always be maintained at 0.78MPa. If the reading drops, it means there is a leak in the evaporator.
2. Fault diagnosis method of exposed TEC EVAPORATOR
For the exposed TEC EVAPORATOR, the low pressure should be applied first to see if there is any leakage in the low pressure pipeline, and then the low pressure segmented pressure should be carried out to determine which evaporator is leaking.
1) Fault diagnosis of the evaporator with the interface in the freezer compartment: Take out the drawer in the freezer compartment, open the upper and lower evaporator welding ports with gas welding, and then pry the evaporator fixing clip with a screwdriver to remove the freezer compartment. Of the evaporator. Next, pressure the outdoor evaporator of the freezer outside the refrigerator to check for leaks. The specific method: first weld a vacuum pressure gauge at one nozzle of the freezer evaporator, weld the other nozzle, and then fill the evaporator with nitrogen. 0.78MPa,'observe the reading of the vacuum pressure gauge after 24h. If the reading drops, it means there is a leak in the freezer compartment evaporator.
2) Fault diagnosis of the TEC EVAPORATOR with the interface outside the box: The first step is to open the interface boxes of the upper and lower evaporators, and then press the low-pressure pipeline in sections according to the direction of the refrigeration pipeline. There are five ways to connect the upper and lower evaporators according to the direction of the refrigeration pipeline.