The first two were found and bought in the first two weeks, but the third one took a little longer to find.

It's not that the third pump was hard to find, it's just that the pumps I need don't come on the market super often, so I just had to be patient.

As I've said before, the idea of taking what was once a really expensive, highly engineered piece of kit and using it in a system that could never really justify buying new, but could greatly benefit from industrial-level reliability and performance, is kind of a fetish of mine.

I've done it with everything from high-altitude thermal vacuum chambers to the alternator on a Lexus for an exercise sled; I LOVE using badass rugged older gear in new projects.

The first step is to figure out what you actually need. In my case, the core requirement for the SanRemo Cafe Racer is supply between 29 and 65 psi and NSF 61.

Secondary to that was fitting in with the other pumps and having interchangeable parts where possible, so I knew I wanted a Grundfos.

That left me with looking for a pump in the CRN1S lineup, with anywhere from 5 to 10 stages, where each stage adds anywhere from 10-20 psi.

I had a few more restrictions, mostly from earlier decisions like circuit breaker/line reactor/VFD sizing. I knew I didn't need a huge pump (hell, this is overspec'd as is), and on the electrical side I'd sized for 0.5hp or lower.

The pump motor also had to be 60 Hz (obvi, using this in the US), 230V and 3 phase so we could control it with the VFD.

So there's our spec, which I wrote up into a `distribution-pump-spec.md' doc and fed it into a custom tool I built called 'ebay-finder' that helps me narrow down what I'm looking for.

I've dropped the actual doc in at the bottom so you can see what that looks like.

The tool returned 216 active matches, though only one scored higher than 60, which is usually what I look for. It missed the NSF61 plate, so when I opened that top listing (scoring 78), and saw it, then verified the rest of the pump's stats, I put in an offer.

Top 3 search results:

I opened the number one listing (scoring at 78, which is excellent), verified that the ebay-finder tool had missed the NSF61 marking, and submitted an offer.

The next day I woke up to a purchased pump. What did I buy?

Grundfos uses an alphanumeric system to tell you what you're getting with their pumps, in this case:

CRN1S-5 A-FGJ-G-E-HQQE

CRN1S-5           A     FGJ         G        E             HQQE
└────┬─┘          │     └┬┘         │        │             └┬─┘
  family stages   │      │          │        │              │ 
               version   │          │        │              │
                       connection   │        │              │ 
                                  material   │              │
                                          o-ring elastomer  │
                                                        shaft seal

• CRN1S: The family of pumps with (relatively) low flow and a stainless steel base
• 5: 5 stages (the number of impellers)
• FGJ: Flange/G (DIN-ANSI-JIS) a combined connection allowing the pump to be bolted to various international piping standards
• G: 316L stainless steel, a material upgrade
• E: EPDM, standard for water applications and compatible with the E in the HQQE seal
• HQQE - H = balanced cartridge, QQ = silicon carbide/silicon carbide faces, E = EPDM secondary seal.

This will easily provide what the SanRemo needs and more. At 3 gallons per minute it pushes ~110 feet of Total Dynamic Head, or about ~47 psi.

Now, any coffee machine geek knows that no coffee machine out there will use 3 gpm or anything close. Running a 3 group wide open and the hot water tap running will cost you well under 0.5 gpm.

So why use this pump? Stability. Industrial pumps are rated at higher flow rates than some $100 Amazon pump. This means when the Racer does demand any amount of water, the pressure doesn't sag. In fact, running the pump to deliver 47 psi is running it in its lazy zone; this thing is loafing even when the cafe's banging.

The bigger picture here for the Paleo Treats coffee experience is to deliver superb coffee effortlessly and fast. THAT'S why I'm overspec'ing these pumps.

Now, under $800 for this pump seems like a good deal, however... Since this is a custom skid and we're not ordering new from the factory (at something like $3k for a new pump vs the ~$730 I paid), I also have to factor in the costs for adapting from the 1" ports.

Assume that'll be another $200 or so, and I'll still have gotten a ripping deal on a monster that doesn't break a sweat when the line is 10 deep and they only ask for more, more, more...

As I was taught many many moons, ago: Proper prior preparation prevents piss poor performance

Be prepared!

Distribution Pump Spec Doc​

Distribution pump for the water skid: T-102 → espresso machine + drinking water station. Driven by an existing VFD-103 (½ HP, 3-φ 230 V output, 60 Hz).

## 1. Pump

- **Grundfos CRN1S** [CRITICAL]
  - Reject any other brand
  - Reject any other Grundfos family: plain `CR` (cast iron), `CRI`, `CRT`, `CRNE` / `CRIE` / `CRE` (built-in VFD)


- **Stages: 5 to 10** [CRITICAL]
  - Duty: 30 psi @ 3 gpm = ~70 ft TDH. CRN1S-5 delivers ~110 ft at 3 gpm
  - CRN1S-12 and larger overload the ½ HP motor and VFD-103

## 2. Motor

- **3-phase, 230 V, 60 Hz, ½ HP** [CRITICAL] [VERIFY: photo]
  - Reject single-phase, 50 Hz-only, 460 V-only, motors larger than ¾ HP

## 3. NSF/ANSI 61 [VERIFY: photo]

- Grundfos CRN catalog-level approval is sufficient
- Nameplate stamp preferred; EU-built units carry CE/EAC only — accept

## 4. Seal

- HQQE preferred (matches P-101 / P-102 spares)
- Any seal with EPDM (`-E-HQQE`) or FKM (`-V-HQQV`) acceptable
- Reject Buna-N (`B`)

## 5. Price

- **$700 – $1,500** used
- Above $1,600: buy new from PumpWorld for $1,953 (Grundfos PN `99915671`, CRN1S-8 baseline)

## 6. Search Keywords

- "Grundfos CRN1S"
- "Grundfos CRN1S-5"
- "Grundfos CRN1S-6"
- "Grundfos CRN1S-8"
- "Grundfos CRN1S-10"
- "Grundfos CRN1S A-FGJ"
- "Grundfos 99915671"
- "Grundfos 96515905"

The basic sequence is:

1. Protect the treatment equipment.
2. Remove the stuff in your source water you don't want.
3. Make a clean blank slate.
4. Add back exactly what you do want.
5. Deliver that finished water at the right pressure.

There are an awful lot of "it depends" in treating water, all centered around what your source water is. Is it Berlin-hard or Seattle-soft? Is it treated with chloramines or chloride, or is there some other method?

I'll start here with the cop-out that your water is probably different than my water, and I designed this system for my water. Still, the basics are the basics. Physics is physics. Testing is testing. Figure out what you have, then solve your problem.

1. Protect The Membrane​

Depending on your source water, a good way to start may be to soften the water.

A water softener does ion exchange: it swaps hardness ions, mostly calcium (Ca2+) and magnesium (Mg2+), for sodium (Na+) or potassium (K+) ions. Calcium and magnesium form scale. Sodium and potassium generally do not form the same hard mineral scale under normal cafe-water conditions.

That matters because scale can foul filters, valves, heaters, and especially RO membranes. Softening does not make the water pure, and it does not remove total dissolved solids in the way reverse osmosis does. It mainly changes the form of the dissolved minerals so the downstream system is easier to protect.

2. Filter Specific Problems​

Then you filter the water.

Different filters solve different problems:

• Sediment filters remove particles. This is where micron rating matters.
• Activated carbon filters remove chlorine, tastes, odors, and many organic compounds.
• Catalytic carbon or chloramine-rated carbon filters are used when the incoming water contains chloramine, which is harder to remove than free chlorine and needs the right media and enough contact time.

The point is not that one magic filter fixes water. The point is to identify what is in the feed water and choose the right filter media, sizing, and service interval for that job.

3. Make A Blank Slate​

Then you pump the filtered water across an RO membrane at the right pressure and flow.

Reverse osmosis rejects most dissolved ions and many other contaminants, producing low-TDS permeate. The pressure, membrane size, recovery rate, and waste flow all matter. Run the membrane poorly and you get bad efficiency, short membrane life, unstable output, or all three.

While it's common to run an RO membrane on city pressure, that's not optimal by a long shot. It'll still work, so don't go crazy and starting buying mega-pumps, but just know that what you've got is on the "easy but not excellent" side of the optimized scale.

4. Add Minerals Back​

Once the water is clean, you add minerals back at specific doses. In this system, the practical mineral set is:

• Magnesium sulfate
• Calcium chloride
• Sodium bicarbonate

Those minerals let you control hardness, alkalinity, and final TDS for the coffee, tea, ice, or drinking-water profile you want.

5. Deliver It Correctly​

Finally, you feed the treated water to each use case at the pressure it expects.

For example, the Sanremo Cafe Racer wants an incoming water line between 29 and 65 psi. Other equipment has its own requirements. Good water chemistry is only useful if the system can also deliver stable pressure and flow.

That is the whole shape of the problem: protect the equipment, remove what you do not want, make a blank slate, dose minerals back in, and deliver the result correctly.

What makes JCWS so goldang special? It really comes down to how much water can be produced, the quality of that water, and the tightness of the specs of the produced water.

1. Architecture​

The skid uses three separate pumps — RO high-pressure feed

• UV recirculation / transfer
• distribution to the bar (P-103)

Plus two stainless buffers (raw permeate (RO cleaned water) in T-101, then fully treated product in T-102). On top of that, three Grundfos DDC 6-10 metering pumps handle minerals only; dosing is not piggybacked on a "water" pump.

Tank 1 is not passive storage. Permeate is continuously recirculated through a UV unit on P-102 so water waiting in the tank remains clean. The engineering spec targets USEPA-grade UV dose with 4x the required margins at the actual recirc flow (see System overview §2.2 / §3.5).

Let There Be (Clean) Ice​

The ice machine should not have to drink your espresso recipe. A valved branch that sends UV-treated RO permeate straight to the ice maker, bypassing mineral injection, means your ice stays unmineralized and clean, and the UV doesn't allow mold to grow, which is common in RO/ice setups without it.

All of the hydraulic pumps are overspec'd relative to typical cafe duty, usually by a factor of 2-3x. This means they can run cooler for way longer, and if we ever add in more filtering or treatment, we'll never have an issue with getting the water where it needs to go.

Having this amount of control over pressure, storage hygiene, and which loads get which water is something municipalities and industrial loops do. It is not something most cafes do.

2. True High Pressure RO​

The first hydraulic pump drives water through the RO membrane at much higher pressure than standard municipal line pressure. Municipal water pressure is often in the 40–80 psi range. That's not enough for high performance RO.

Without going deep into mass-transfer math, RO is materially more efficient when you operate the membrane up in roughly the ~175 psi class — well within what this pump and Filmtec XLE Pro-2540–class elements are built for. A few high-end packaged systems do something similar; most cafe skids do not.

This means you're wasting far less water, and the membrane is working much less hard.

Downstream, the design intent is a near-blank permeate so *what you taste in the cup is the coffee, not the city water hiding under it.

3. Precise Control​

Individual metering pumps inject magnesium sulfate (sweetness / clarity), calcium chloride (body), and sodium bicarbonate (buffering).

The metering pumps we use (1 pump per solution) are rated 0.1–100 mL/min each, with 1000:1 turndown. This is the equivalent of dosing as low as two tiny drops per minute (think standard medical dropper) into a continuous defined stream.

Rather than adding a pinch of salt to a gallon and shaking it up, hoping you get great distribution and that you're not off by a gram, the JCWS metering system gives you exactly what you ask for.

Because we're also using the larger distribution pumps to move water past the metering pumps, we have extraordinary control over how much water flows through the pipes and gets dosed.

Compared to a dissolving cartridge of minerals that may have channeling, uneven flow rates, or even run out without you knowing, this level of precision and control is on the level of NASA-level telemetry vs a 1998 Honda Accord.

Hondas are great cars, but they won't get you to the moon.

That combination is what precise control means here: you are not adding in a cartridge and hoping it's close enough for your washed Ethiopian vs the co-fermented Guatemalan you just ran.

You change the active recipe targets for the final water, including different end uses (espresso, drinking water, matcha, etc.) on the fly to exactly what you need.

Want to nudge sulfate a few ppm relative to the last roast? The path is precision dose and verify, not pinch 'n pray.

By contrast, a typical hand or cafe recipe is in the range "0.25–0.5 g of the first two salts" and "a pinch" of bicarbonate. Pinching is for grade school, not excellent coffee at scale.

4. Instrumentation and obsession​

The JCWS tracks everything in the system in real time, including pressure drop across the membrane, permeate and feed conductivity / TDS, temperature, pH, and the pressure the espresso machine sees.

Most water systems might tell you water pressure and TDS coming out the far end, and those are the high end ones. Tracking what each stage does (and whether or not it's working the way it's supposed to) is the hallmark of industrial process control.

If you want reliably superb water for coffee, nothing less will suffice.

That drive for reliable excellence, backed by blood & treasure, is what makes JCWS a worthy obsession for me.

Happy watering!

For the full flow diagram and component list, start at JCWS system overview.