Retired now, read posts on here and don't know half of what you post about.just remembering being an apprentice, only 3 gases then, R12,R22 and R502 just coming in.Earned £4 a week for 1st year, Going from work on domestics to refrige on Super tankers, trawlers small and large, ferries and a 160 hp(2x80) 3cyl sternes r22 low temp c/r and ending up on supermarkets.every call was an adventure, got paid good money for sitting down driving thousands of miles a year.Worst job? mortuary fridges with bodies in.Best job, finding the fault.Too many gasses now,too many regulations, glad to be out of it, trouble is its in my blood. Anyone used a tilley leak detector?