Plumbing a Londinium Compressa

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ShotClock
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#1: Post by ShotClock »

Hi all,

I'm trying to figure out if it's feasible for me to plumb a Londinium Compressa to my home RO system. After the filters, i have around 2 bar of pressure. I normally drink espresso at the darker side of medium - city+ to full city in roasting terminology. Will this be sufficient pressure? Can i boost this pressure with a pump?

relax

#2: Post by relax »

Plumb line pressure for Compressa is for pre-infusion, it is good at 3 bar. But I think 2 bar is also OK as you could tune it by adding one or two second.

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JohnB.
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#3: Post by JohnB. »

ShotClock wrote:Hi all,

I'm trying to figure out if it's feasible for me to plumb a Londinium Compressa to my home RO system. After the filters, i have around 2 bar of pressure. I normally drink espresso at the darker side of medium - city+ to full city in roasting terminology. Will this be sufficient pressure? Can i boost this pressure with a pump?
Dipper/boiler fed spring levers do well with the roasts you like using boiler pressure PI which is usually 1.2 bar. I don't see why 2 bar PI would be a problem with the Compressa. Plus you still have the option to grind finer & preinfuse at a higher pressure by holding the lever at the spring engagement point when you lift it after the group fill. With a 1.2 bar boiler pressure this gives you 2.5-3 bar PI so with your Compressa's 2 bar fill pressure you should easily hit 3 bar PI or higher using this method.
LMWDP 267

emradguy
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#4: Post by emradguy »

I agree you will be fine. Though Reiss recommends using up to 6 bar to preinfuse light roasts.

ShotClock (original poster)
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#5: Post by ShotClock (original poster) »

Thanks a lot for the tips. Having read a little more about the difficulties associated with remineralization for RO water, I'm starting to think this is not as simple a solution as i thought.

PeetsFan

#6: Post by PeetsFan »

RO water isn't the best for coffee. Do you have a water quality report which indicates a need for RO?

ShotClock (original poster)
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#7: Post by ShotClock (original poster) »

Thanks, my town's water report is here:

https://concordma.gov/DocumentCenter/Vi ... -Report-CY

We don't have a lot of calcium in the water, but we do have a lot of chloride. Since i understood this to be particularly bad, I have been using RO filtered water with potassium bicarbonate added in the amount suggested by rpavlis. I thought this was a suboptimal but decent enough solution for my current tanked machine.