Euology101 wrote:Not sure what your set up looks like, but I did this with my GS3. It's not plumbed in, but to say the water lasts a lot longer, would be an understatement.

Apologize for the mess, the doors were off the cabinets at the time of the photo.

Do you also have an external pump and an external reservoir to imitate the line pressure?

ira wrote:Now that they are possibly discarding 10 shots or maybe more worth of water for one shot pulled, they might not want to assume there is enough water in the tank to make one more shot when the sensor triggers.
Ira

Are they really pushing that much out the exhaust? I admit, I thought the ~6 shots off a full reservoir was a gross exaggeration. If they are passing that much water out of the exhaust, I'd like to see a video showing this. If anyone has a link, please share.

Mayhem wrote:How exactly would you expect the shot to continue flowing if there is no water left in the reservoir?

Magnus, on my machine when the "Refill Tank" comes on there is still a sizable amount of water in the reservoir (guessing nearly a liter). The water level sensor that trips the low water warning is much higher than the pick-up tube. In fact, the pick-up tube sits in its own recessed cavity that extends below the lowest level of the reservoir. You'd have to have gone through nearly all 3.5 liters of water in order to lose your supply of water.

Measuring my reservoir I see it is 2.5" tall. The water level has two sensors for obvious reasons - completing a circuit. The lowest probe sits just above the base and the top sensor which triggers the "Refill Tank" sits about 3/4" up from that. That space between 3/4" (top) and just above the base (bottom) is usable during a shot on my machine. Again, this is about a liter of water.

Image of reservoir - crude, but gets the point across.

DaumierS wrote:Do you also have an external pump and an external reservoir to imitate the line pressure?

Not Eulogy, but FWIW, mine is running off the 3.5 liter reservoir. Not plumbed in or out.

Just ruined yet another shot. Got to 6.5 g of beverage during 8 seconds and "fill the tank". Actually, very annoying, especially in the morning. At least LM had to put an advanced warning or something. And after refilling the tank the boiler temperature drops to below 190 F, and I have to wait before it gets back to 200.

Filling the tank now has to be a necessary morning routine, which, I guess, should solve the problem.

One full tank = 5 or 6 shots, if you preinfuse for 30 seconds, and use 3-6-9-3 bar profile. This 3 bar stage is losing a full glass or two of water. May be I should look at this from a positive standpoint - at least the water in the cup is always fresh. But now I regret I did not get Strada MP one group from Canada. The GS3 idea of conical valve is not the best. Instead, manipulating the boiler pressure seems to be a better technical solution, perhaps.

DaumierS wrote:One of the reasons I decided to choose GS3 MP (and not Slayer or Synesso) was its water reservoir. Now, I use from 1/2 to 1 gallons a day, which is $15 extra per month. Not that I regret, but I wish it would be written somewhere and I've read it before.

There were warning flares: Introducing the new La Marzocco GS3 MP.

There is one more minor thing I discovered: I used an IKEA power extension cord with a 15 circuit breaker that breaks the line every now and then (even with the GS3 in a power save mode, one boiler at a time). You need to use a 20 amp cord (for AC, say) and your outlet should be wired for 20 amps. But this is a standard for kitchen outlets, I guess.

Without the heavy flow to the exhaust port, the minimum pre-infusion (PI) flow rate and ramp time to full pressure would be limited, possibly so much that flow profiling wouldn't be possible. Also, you'd probably have a lot less control over the shot profile.

Bear in mind that the rotary vane pump is fixed speed, with the flow rate and pressure determined by that speed, the pump bypass valve, the size of the opening to the puck and the size of the opening to the exhaust port.

Suppose there's no exhaust port and you start with the smallest possible opening to the puck. During PI, you won't be able to go any lower than the flow rate permitted by the size of that opening and the permeability of the puck. With the exhaust port, a large percentage of the flow is diverted, allowing the minimum flow rate to the puck to be considerably lower.

In the no-exhaust-port case, once the basket fills the ramp to full pressure is also determined by the pump flow rate and the size of the opening to the puck. Given the power of the pump, the ramp is likely to be quite fast -- and it can't be any slower. With the exhaust port, you can slow it down a lot because much of the source flow is diverted away from the puck.

I think it's really the choice of the powerful fixed-speed rotary vane pump that dictates the exhaust port requirement. Lots of flow. The current-limited gear pump used in the Slayer, which is designed to work at a user-selected fixed speed during the shot, behaves quite differently when the opening to the puck is restricted by the needle valve, so a bypass to an exhaust port isn't needed. The Strada EP, which uses a similar gear pump but without current limiting, uses variable speed during the shot to control the flow.

On additional thought:

The high water consumption only takes place when you profile, which is probably something you only need to do for very light roasts. if you pull medium-light, medium or dark roasts, you probably shouldn't be profiling. In that case, the reservoir is a workable configuration.

Peppersass wrote:.

Thanks Dick. Looks like Strada EP 1 group would have been a better option for me. I did not choose it because of its large size and the 220 voltage.

Perhaps I should consider plumbing my GS3 in. Would appreciate a link with instructions and options. What would be the best filtering system? I know Chris sells some, but what would be the best system from the health point of view, and hopefully low in maintenance?

DaumierS wrote:Thanks Dick. Looks like Strada EP 1 group would have been better for me. I did not choose it because of large size and voltage.

Perhaps I should consider plumbing my GS3 in. Would appreciate a link with instructions and options. What would be the best filtering system? I know Chris sells some, but what would be the best system from the health point of view, and hopefully low in maintenance?

Don't be tempted to plumb it in without plumbing it out.

The machine is designed so if anything "bad" happens (like a solenoid stuck open, overheating, stuck check valve, etc) any water flow would get directed to the tray. This can be catastrophic in terms of water damage to your household if the tray is not plumbed out.

I know some here do this - but I have had at least 1-2 times that this happened and a steady stream of water ended up in the tray.

It is a bit annoying as the drain pipe has to be slanted downwards and has to end up in a sewer line. I sort of wedged it in using an "amply suitable" Tee secured using pipe "screw" binders to the In-sinkerator.

Also - I think Dick may be suggesting that you can try to preinfuse at a higher flow rate. That would result in a higher water to puck vs. water to drain ratio. At least I think that is how it works.

AV versions do not shutdown mid pour. But then all they can consume is about a shot. I wonder if the AV version shuts down mid tea water. I haven't used the reservoir in 7 years....

You'll never regret plumbing in your GS/3. It's a great pleasure not to have to fuss with filling a reservoir or tank and not having to empty the drain box. It lets you concentrate more on making coffee.

How to do it depends a lot on factors specific to your home -- location of the water source, mineral composition of the water, location of drain pipes, available connections, counter material, space below the machine, etc. You'll find quite a few posts on plumb-in projects and water treatment by searching the forums on this site. Here's one I did on My Plumb-in Project