Good old t500 again

[Bradd79]

So this arvo I decided to run my tpw through the t500 have done this same wash several times b4 but this time it just wouldn't run. Temps were up and down ( I have still spirits water pump/reg thing) spirit would start and stop then I guess you call it puk out a heap. After trying to work it out I gave up and pulled all the packing out I know most of yous say not to do this but in the book that's how it says to run to distill water. I thought seems it's been a pain wash and potentially my last run with the t500 ill try throw the peel of a lemon in above a small scrunch of copper wool and man its running like a dream and my best tasting guess it's still neutral yet slight lemon flavour but a heap cleaner than every other time.
Question is why am I getting off flavours with the stock packing I clean it every 3 washes or so. T500 is stainless with the standard bits of copper and stainless inserts