I was pulling some shots today on my Brugenttii and I was thinking they were sour....
WHY WHY WHY i start thinking. Beans are fresh i roasted them, pump pressure is fine, grind adjusted, extraction looks ok.

hmmmmm water temp water temp ????

I put my thermocouple and pid onto the shower screen. water temp was only 86 deg (max) :o :-? :-/

I wind up the sari, find a 93 deg "zone" and the shots come back to being "better"

Now I start thinking WHY WHY WHY again? whats causes it to change? diaphragm wearing out on the sari? something else? Its getting hotter in SYD, i would have thought the machine might get hotter not colder?

Who has checked there machine of late and noticed a change?
How often are you changing things effecting the boiler etc (pstat)?
How often should we check these things (or need to)?
Thoughts?