I have just begun putting together a plumb-in system for my (soon to arrive [hopefully]) DD. I just ordered all the parts yesterday for the filter system . I have placed an article on my website with details ("Plumbing in an Espresso Machine - Part 1" in the "Coffee College" area). Here is my isometric drawing of the final plan:

It is all John Guest. The left 1/3 of the drawing is under the kitchen sink.
Water comes in at Stop Valve (D). Through one-way valve (14), through the double cartridge softener system from Chris Coffee (C). From there we have three outputs:
- Through the valve (5) to a sink-top faucet
- Through valve (8) to ice maker
- At the end of the line (far right), through the valve (11) to the espresso machine.
I can use the faucet (A) to flush the system when changing cartridges. It is all being run with 3/8" tubing.

If I have planned it well and have all parts I need. The total up to now is $220 including the faucet tap above the sink as well as a new Stop Valve under the sink (dual 3/8 fittings) . My pressure is relatively low so I should not need a regulator from what I have read. Easy enough to add anyway later on.

Part 2 of the story should appear in about two weeks which will cover the actual installation of the system.

I'm interested to know how your project goes, Randy, as I will be undertaking a similar project soon, having just received my new vbm double boiler from Stefano. Keep us updated!

By the way, is the steel hose that comes with the machine represented here? If not, what is the last fitting before the connection to the vbm hose?

My drawing of the planned system just shows the plumbing. The hose from the back of the machine is 3/8" BSPT MALE. From what I have heard, most plumbed machine ahs a hose that terminates in female threads.

Stefano has the hard to find proper adapter if you are going to use JG plumbing. I have been told that 3/8" NPT will work if you use teflon tape on the threads. More info on thread sizes HERE. The "T" indicates 'tapered' threads. The two are very similar other than a slight difference in the angle of the threads - 55 degrees vs. 60 degrees. You would think that machines sold here would be adapted to the correct threads for this country, but there you go. As long as both sizes are the same (3/8") and are tapered (T) they will (should) work with sealant as long as the pressure is not excessive (In this case, they should be fine at the 30-40 psi recommended for rotary espresso machines).

The remainder of my plumbing parts arrive here tomorrow and I hope to have the system in and working by the end of the weekend, or early next week. I did receive the two-cartridge softening system from Chris Coffee and the filters are already mounted under the sink (that was a joy). I got my first chance to mess with the JG fittings and I like them a lot already. I made a little jig to hold the tubing while I cut it, and as long as the cuts are square and clean the system goes together easily.

I finished the installation of my filter system yesterday.

Here's the under-sink installation. The valve to the espresso maker is closed in this pic because I wasn't finished with that final leg of the system when I took the pictures. That portion was finished yesterday. I can say that working under the house with JG plumbing makes it a lot easier.

The filter system is from Chris Coffee. All the rest from eBay:
- All the JG fittings and tubing
- The counter-top faucet tap
- A stop valve with dual 3/8" npt fittings

The full story with installation details is on my website.