The blue tube was the one with water in.
If it happens again tomorrow I’ll pop the lid and have a look.
Penance so far there’s nothing abnormal. Let’s see what tomorrow brings and go from there. It might have been residual water in the tube from the Expansion Valve (blue).
I reckon you’re right. Was surprised to see it but after talking with BB and the great support here my worries have abated.
Back to looking at grinders.
My little Profitec makes lots of strange gurgly noises and puts a small quantity of water into the drip tray as it warms up, always assumed and hoped it was normal but nice to know it is.