Viking DFUW244CL, Руководство по обслуживанию

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3.5 Sealed System
The following should always be practiced with any sealed system that has been opened. Only open the
system after a complete diagnostic evaluation of all electrical and mechanical components has revealed
that a definite system problem has occurred. Items that could cause similar failures are loose or broken
wiring connections, fans, bad control, faulty thermistors, door gasket leaks, misc. air leaks, and dirty
condenser. The diagnosis of a sealed system can be determined by accurate pressure and temperature
measurements.
1) Use a leak detection system that will detect R-134a refrigerant. A small charge might have to be
added to the unit if the leak was critical enough or the unit has set for a period of time before
service.
2) Find and repair the leak. Look for traces of oil around solder joints. This is a good tool to pin-
point a leak in a tight area.
3)
Remember that any charge in the system must be reclaimed prior to repairing the leak.
4) Replacing the filter drier is mandatory when ever a system repair has occurred. Using a dirty
filter / drier will increase the percentage of system failure. Moisture and other non-condensable
material are detrimental to the operation of the refrigeration system. Do not open the new sealed
filter / drier until ready to install and solder the system closed.
5) It is also recommended that the compressor be replaced if a low side leak was found. The com
pressor has drawn moisture into the system at the point of the low side leak. Dry nitrogen gas
should be used to flush the system prior to evaluation.
6) In the case that the capillary tube has been restricted or kinked a new evaporator will also be sup
plied as a sub-assembled piece.
3.6 Low Side Leaks
As mentioned above it is recommended that the compressor and filter / drier be replaced if moisture has
been drawn into and contaminated the system. After repair, dry nitrogen should be flushed through the
system before the unit is evacuated and recharged.
3.7 High Side Leaks
It is not necessary to replace the compressor with a high side leak however the filter / drier should be
replaced. Once again after the leak has been repaired, flush the system with dry nitrogen before evacuat-
ing and re-changing the unit.
16
2010 - Viking Preferred Service SMR-0005