When I was working on refrigerators, we had a capillary tube clearing kit. It had a hydraulic pump, and a selection of lead slugs, for the different ID’s of cap tubes. The tube was cut at the dryer, the slug put in the cap tube and the pump connected to the cap tube. The idea was that the hydraulic pump would develop enough pressure to force the led slug thru the cap tube clearing any obstructions. The instructions said the slug would pass harmlessly into the evaporator. I can’t remember if it worked. That was back in 1977.
It usually worked very well. It could get up to 3,000 lbs or more of pressure on the cap tube only. You could opt for just the hydraulic oil and that worked pretty good as well, . One time I cut the lead piece too long and it jammed up on the inlet of the evaporator. One factor that is often overlooked is that the condenser can get clogged with oil as well.. We usually would blow out the condenser with nitrogen to keep from having to go into the system twice. I have found R134 restrictions much harder to deal with than the old R-12 systems. because of more oil thickening proclivities in the 134. Sometimes the evaporator can become slugged with oil and then it is usually better to replace the evaporator. Sometimes if it's only a clogged cap tube that resists cleaning out the best solution is to replace the whole heat exchanger (cap tube and suction line )but that is not too cost effective out of warranty. Before you decide to do a restriction job on a 134 system, you had better warn them that a simple drier exchange and capillary blow out may not correct the problem; it may be a waste or their money and possibly your time and reputation as well.
What if there's only a PARTIAL restriction of the tube? Would this blow that out as well or do I need to look for piano or guitar wire to "pipe-clean" the tube to help the pressure clean out the partial restriction?
There no need to cut the suction off the compressor you can blow thought the inlet port on compressor thought housing and not need a process adapter Do not know why i bought one never use it. Now 75% it oil in evap. and your not going to blow the oil out of the evap time to replace it. or remove it blow out with evap upside down. But if i remove one i replace it.
I've done that about 4 times now and the damn freezer is still not freezing ice cream properly. Changed filters all those times, did vacuum, checked for leaks and still nothing man!! I don't want to give up though.
Thats why its best to change the cap tube and if it doesnt work they need a new unit. The ammount od work this takes may aswel change the part. Especially if it has a concealed evap in the walls probably has a leak.
Sometimes the nitrogen does not truly clean the cap tube and it needs to be replaced. But in a 134 system you may have restriction problems in other places as well, If the oil has got thicker by other problems such as contaminants and overheating, it may be better just to replace the refrigerator.
You cannot establish with this procedure that cappilary tube has no obstructions. It can only be known that cappilary is not completly obstructed. That does not tell you that cappilary is not partialy obstructed. Please clearly state that in video description. BTW realy nice video!
