Dont suprise me at all.They are constantly dummying down this trade.Too many people buying tools without knowing how to use them.I see it every day,people take some classes and buy a couple of tools and presto! they a tech! Yestaday i couldnt spell heat aircondition service man,today i are one!We should be required a minimum of years in trade before we can work on them alone and even pass a practical exam to demonstrate skill proficiency.Not to brag, but ive never burned up either a reversing valve or txv or service valve.Always too paranoid of ruining it that I guess I over do the prep a little(usually use hot dam AND wet rag)and always nitrogen(didnt used to but last several years all the time)even used 15% for years without nitrogen and no problems(use 6%now flows alot better with a little less heat).Learn it and practice good techniques and you shouldnt have problems.
Outdoor txv? I replaced one on friday that came with the distributor, i just unbrazed it rather than unbraze/rebraze 4 feeder tubes. I have another on Tuesday to do. Seems to me there are too many txvs failing. How did yours fail? I've seen many problems with either the equalizer tube splitting open or seeing the cap tube breaking off at the sensing bulb.