macaber8 wrote: Does this mean, in this setup, the preinfusion pressure is now controlled by this external pressure regulator?

Yes; the Compressa PI pressure is whatever is presented to its water inlet. The regulator goes between the accumulator output (~6 bar constant) and the Compressa input.

For what it's worth, I'm using mainly medium roast beans these days and leave mine set at 4 bar (close to my nominal city water pressure) 90% of the time. Sometimes going to 5-6 bar for very light roasts.

I'd really appreciate any input on compressa plumbing setups that can work with a 5gal container. I've been looking into the Caffewerks pump/accumulator systems and shurflo system. My main struggle with this is I'm not knowledgeable in plumbing and lack confidence. The shurflo looks awesome because it's pressure is set to around 6 bar and would be perfect with a adjustable regulator.

What happens if the water runs out and I don't notice- can it damage the machine?
I have been told it's normal to leave the pump on? Does that mean that this constant pressure can wear some parts down? Do I need to have a shut off valve and turn it off and on every time I use it?! Thanks all!

Probably I dumb question that I'll figure out once I install my Compressa, but to check the water pressure, do you have to check the regulator gauge during the Pre-infusion phase of an actual shot?

Thanks!

you should have an in line gauge fitted before connecting to the machine

personally, bare minimum a carbon block, pressure reg then to the machine, but test your water as last thing you want is scale in your machine, they sell dedicated filters that will create the safest water for your machine

Trouton wrote:What happens if the water runs out and I don't notice- can it damage the machine?
I have been told it's normal to leave the pump on? Does that mean that this constant pressure can wear some parts down? Do I need to have a shut off valve and turn it off and on every time I use it?! Thanks all!

I have the Shureflo system for my Compressa, hooked up to the water mains. While its pump is self-priming with a pretty decent lift, I don't think I'd be comfortable with it running for hours/days without water. You may want to check the specs for the system with Shureflo and see what they say, but my guess is you'll have to have way to disable the pump while the system is unattended if you are concerned that the water source may run dry. I don't think the Compressa will be damaged - it has a low-water sensor in the tank which will turn off the heater if it runs dry.

Note that the Shureflo pump doesn't run constantly, and usually not when you pull a shot. It will only run when the accumulator pressure drops below a certain point (4-5 bar); the pump then runs for a minute or so to get the 2-gallon accumulator back up to pressure. With my volume of espresso (2-3 shots per day typically), it might go a week or more before the pump recharges the accumulator.

I leave the output of my Shureflo system (6 bar) connected to a pressure regulator (normally set to 4 bar) and then to the Compressa continuously. No concern here about damage to the Compressa. The only issue would be if you had over 6 bar pressure make it to the Compressa, which could force the input solenoid open and potentially cause a flooding situation.

If I go away for a week or more, I generally unplug the Shureflow and turn off the water mains. Otherwise it stays enabled 24/7.

Steak wrote:Probably I dumb question that I'll figure out once I install my Compressa, but to check the water pressure, do you have to check the regulator gauge during the Pre-infusion phase of an actual shot?

Pre-infusion pressure is the line pressure presented to the Compressa prior to starting the shot.

Thanks for the great info. I'm sold on a simple lever machine. After using the compressa for a bit any reason you'd feel tempted to run a vectis type of machine? Reiss says for home use 6 or less a day that the compressa isn't completely necessary. He also said its output weight of espresso is around 36g. Do you find yourself pulling bigger shots than that?

I like the convenience of a plumbed in machine, so the Compressa is perfect for me. I also like the ability to control PI pressure depending on bean that I'm using.

If I weren't in a position to plumb in I might look seriously at a Vectis over an R24 to keep things simple, but would have to see reports on how it handles a variety of beans including light roast, and what the typical/max dose is. My understanding is the Vectis, as a dipper machine, is limited to boiler pressure PI. I'm comfortable with 18g - 19g doses now but expect the Vectis may max out at 15g?

@macaber8 were you able to get a setup going? I just bought a Londinium Compressa + setup a tank/pump/accumulator setup. Also located in SF.

Flojets won't work well. Not enough pressure for great results.
Consider even a stronger pump than indicated in the thread below and a Swagelok pressure gauge for precise control.


Espresso Cart - Goodbye Plumbed In