Low water pressure plumb in

#1: Post by JG » October 2nd, 2021, 11:51 am

Plumbing post

OK, I'm officially need some help of you plumbing wizards out there.

Here is my situation: since I live in a condo on the third floor and the water lines inside the condo leading to the kitchen are very long, my line pressure is super low - 10-15 PSI. It has always been my dream to have a plumbed in lever machine, so I took delivery of a beautiful Londinium Compressa this Fall. My goal is to be able to adjust pre-infusion pressure as precisely as possible by means of a water pressure regulator so I can make use of the compressa's features to the fullest extent. I've been through a lot of different stages with my plumbing, since my situation doesn't appear to be exactly straightforward.

Here's what I have currently arrived at:

The RO system feeds a 4 gallon accumulator, serving both espresso machine as well as the drinking water faucet
T split, 3/8'' tubing leading to ShurFlo water boost system
ShurFlo water boost system (90 PSI pump and 2 gallon pressurized accumulator)
1 ft (too short?) 3/8 tubing leading to adjustable pressure regulator
connected to reading gauge
6' 3/8 braided hose connected to another 6' 3/8 hose (I need about 8', so there is excess length I could remove), leading to Compressa, placed about 3-4' above ground

My main problem: pressure regulation is off; When I pull the lever the needle on the gauge drops to ~18PSI (line pressure) and even if it was resting around 40 or even 60 PSI before, it takes a long time to climb up, affecting pre-infusion.
My grind is currently a little coarser than I know it should be, and still it takes 20 + seconds for any beads to show up on the bottomless. From the reading and the lack of beading I concur that pre-infusion is taking place at my very low line pressure.
I don't understand this, because the pump is definitely working and coming on occasionally, and I checked the pressure of the pressurized accumulator, and it's idling at six bar as it should coming off the pump.

Full disclosure: When I got the pressure regulator, it was calibrated to 60 psi. On top of it it says to loosen the screw to adjust, which I did. This messed up the PSI reading ring, so I unscrewed the screw completely and reassembled. Later, in the manual I read that and the screw must not be taken out completely. I'm now wondering if I messed up the regulator and rendered it unusable.

Next move I'm guessing: exchange the pressure regulator

Anything else I should definitely try/change? Tweak?

Thank you for any thoughts, Jan

October 2nd, 2021, 12:02 pm

The 1st thing I wonder about is whether with 10 - 15psi, you're able to take a decent shower in your condo? Is this pressure up to code? Is it enough to extinguish a fire if there's a sprinkler system? Have you spoken to your building manager or a city engineer?

October 2nd, 2021, 12:43 pm

Are you calling me smelly? i worry about coffee first..
jokes aside, this pressure only applies to what I get in the kitchen. These are long lines supplying dishwasher and kitchen faucet (frustrating hand dishwashing experience for sure) and now R/O faucet as well as espresso machine. Shower lines are shorter and have plenty of pressure.

#4: Post by **Pressino** » October 2nd, 2021, 9:37 pm

BaristaBoy E61 wrote:The 1st thing I wonder about is whether with 10 - 15psi, you're able to take a decent shower in your condo? Is this pressure up to code? Is it enough to extinguish a fire if there's a sprinkler system? Have you spoken to your building manager or a city engineer?

If line pressure coming into a residential plumbing system is >80psi, a pressure regulator is required to reduce water pressure to 80psi or below, according to the UPC. 15psi is the minimum water pressure (measured at the fixtures) allowed by the UPC. My house pressure is around 80psi, and I've got a WATTS valve directly to the machine to bring that down to about 2.5 to 3.5bar (about 35 to 50psi) to feed my plumbed in machine. 10 to 15 psi is definitely inadequate to marginal water pressure for household use. It really shouldn't be much of an issue for making espresso, however, since the pumps in them (both vibe and rotary) can work off of reservoirs, which feed water at even lower pressures.

October 3rd, 2021, 12:29 am

Pressino wrote: 10 to 15 psi is definitely inadequate to marginal water pressure for household use. It really shouldn't be much of an issue for making espresso, however, since the pumps in them (both vibe and rotary) can work off of reservoirs, which feed water at even lower pressures.

Perhaps you might be missing the point here, my apologies if I'm misinterpreting your post. To adequately utilize an E61 machine's preinfusion capabilities with line pressure, more than 10 to 15psi would be required unless the grind was quite coarse, which would defeat its purpose.

We have ours set at 4.5Bar and it does a nice preinfusion job with quite a fine grind and no adjustable mushroom. The object is to pre-infuse the puck before the pump is engaged.

#6: Post by **Jake_G** » October 3rd, 2021, 7:49 am

I don't want to derail this too far, but in the land of dipper levers, 1 bar is sort of the median preinfusion pressure and it has worked just fine for about 70 years that way.

As for the OPs concerns:

You've got lots of line losses you need to account for.
To properly troubleshoot this, you'll need a gauge right after your ShurFlo boost system to see if you are limited by the source flow rate into it (RO can't keep ShurFlow fed, so pressure falls). If this is the case, you should consider putting the RO after the ShurFlo. The RO membrane flows very, very slowly. Even though you have an accumulator, the accumulator is at a marginal pressure to begin with, and I suspect that as soon as the ShurFlow begins moving water to the espresso machine, the accumulator pressure tanks.

Swapping the order should help drastically as the increased pressure feeding the RO membrane will help with efficiency and you'll have a 4 gallon accumulator at your desired pressure feeding the espresso machine. Now, I know you have a 2 gallon accumulator on the ShurFlow, so check the pressure gauge there first. If you have plenty of pressure there, then your problem is line losses between the accumulator and your espresso machine and if you are losing pressure right after the regulator, my bet is that the orifice in the regulator is too small for the flow rates you want and a larger regulator is in order.

Hope this helps.

Cheers!

- Jake

#7: Post by **Pressino** » October 3rd, 2021, 10:21 am

BaristaBoy E61 wrote:...To adequately utilize an E61 machine's preinfusion capabilities with line pressure, more than 10 to 15psi would be required unless the grind was quite coarse, which would defeat its purpose.

We have ours set at 4.5Bar and it does a nice preinfusion job with quite a fine grind and no adjustable mushroom. The object is to pre-infuse the puck before the pump is engaged.

If you're referring to passive pre-infusion (lifting the E61 brew lever to let water into the brew chamber without activating the pump), then yes, you will need higher line pressure. On the other hand, automatic E61 pre-infusion is accomplished with the pump running and occurs from the time the infusion chamber spring opens to when the chamber completely fills.

#8: Post by **Pressino** » October 3rd, 2021, 12:51 pm

And the OP was asking about a lever machine...