Hey lads, just tinkering with the home machine, just added a dual rocker switch to give me some pre-infusion, not sure of the ramp up, but whatever, not too phased. Can someone please explain to me this section of hydraulics?? The ball valve has me confused, goes to a black box at behind the boiler, and goes to a T block on the output of the volumetrics, on that block is a valve, im sure thats for adjusting group head pressure (or is it boiler pressure??) A line comes from that valve to the water IN line to the pump.. Reason for all this is i have a spare rotary pump i want to use, as the vibe is too noisy, and, well im bored and like breaking things.

[IMG][/IMG]