water pressure

mario Pavesi

Hi Reiss

I have a question about water pressure on The LI forgive me but could not find it here but I know I read somewhere, I know you suggested a temperature for single origin coffee and another for blend or darker roasts, so my question is what is the best pressure for dark roast and where is best to read at the machine gauge or at the pressure reducing valve? And for single origin? I know this are suggestions but at it's a starting point for me

Thanks
Mario

Reiss Gunson

hi mario

so the boiler pressure, which is what the gauge on the front of all our machines is showing you, should be set to peak at 1.0 bar just after the heating element turns off. based on my experiments i suggest that the boiler pressure is not altered, regardless of what roast you are using

quite separate from that is, in the case of the LONDINIUM I/II/III, the pressure in the water line that is supplying the machine

what i recommend is a regulating, or pressure reducing, valve to be fitted at the end of the water line supplying the machine before you connect the pressure hose from the machine. this valve should also be fitted with a nice large pressure gauge so you can read it easily (not a silly little 40mm gauge where the scale is so small that you can hardly read the numbers)

if you have hard water or other water composition issues then any treatment system should be placed upstream of the regulating valve

i suggest that you start with an inlet pressure of 3 bar. if you want to run a dark to medium roast then you might want to turn the inlet water pressure down as low as 1.5 bar, which as previously discussed will have the effect of reducing the brew temperature. if you were running a very light roast you might want to try 3.5, 4.0, and 4.5 bar. i can't imagine a situation where you want to go much above 4 bar personally

kind regards

reiss.

mario Pavesi

Thanks Reiss, the information is greatly appreciated.

Mario