Rancilio Z9 Two Group Lever Machine - Page 10

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phillip canuck

#91: Post by phillip canuck »

orphanespresso wrote:The wiring inside the machine can be 10 gauge for the heating element and 12 gauge for everything else (14 will actually surpass the amp rating but will look skimpy next to the 10). Spade terminals will work but eyelets are better as they never loosen. Teflon coated wire is very nice to work with and can be gotten on ebay in small quantities and various gauges...easier to find than silicone coated, at least for me.
Doug! Thank you very much, (very much) for helping me. It seems to me that regardless of what I decide to do via 20amp/30amp circuit, I should plan on wiring everything for 30A (except the power cord, and upgrading to 30A Sirai if need be). This will give me more options in the future should I decide to use this for more than just home use.

Teflon coated wire: I've been searching off and on through most of the day, eBay and elsewhere. I've learned that Teflon coating also goes by the name (generic?) PTFE, and that it is used in body piercings, but I have not found a supplier with less quantity to sell than 25 feet. McMaster-Carr sells by the foot, but they don't seem to carry it in 10 gauge rated for 30A. Speaking of which, I'm quite certain that I'm making a mistake on this one - should these individual wires be rated so highly? The power cord, certainly. And, if not 30A for the heating element <--> pstat, then what?

As mentioned earlier, there is a dizzying array of choices for each category; Conductor Type; Conductor Material; Conductor Insulation Material; Jacket Material; Jacket Color.
orphanespresso wrote: The switch from your wiring scheme sounds like a double pole double throw and can be anything from a simple toggle to more elaborate.
"Your wiring scheme" is exactly that - my thoughts as to what is happening with the current. If I'm wrong, or something could be better, please let me know.
I don't know what a double pole double throw is (exactly, other than a switch) - at least not much more than what I read today online after seeing your post. I do know that if you Google double pole double throw espresso - a switch from your site comes up first.
orphanespresso wrote:
Good idea to lose the gicar as that is one of the more expensive parts to replace. The block junction just acts as a bridge and you insert the stripped wire and tighten the screws....make sure to clean it out well so it does not become a mini heating element!
Did you means to say: Good idea to NOT lose the gicar.. I plan on keeping it, but it seems that it would be an easier electrical project if I left it in safe storage.

Again, thank you, Doug. There are some installation items in your post that I did not address, but for now, I just want to get the proper wires and fittings ordered.
If you happen to look around your shop and see the different wires that I need, feel free to throw them in a box and charge me the going rate (plus) for your expertise and help.


phillip canuck

#92: Post by phillip canuck »

allon wrote:some cheap ring lugs will corrode easily, and the corrosion will work back up the wire, under the insulation - not good. When I wired my CMA lever, I used high temperature range wire from an appliance repair shop, as well as high temperature rated ring lugs.

They were a pain to crimp, but they hold.
Saw this after my post to Doug. Thank you! That's certainly good to know. I should mention that the only reason I keep linking to McMaster-Carr, as I'm about to, is that I remember Cannonfodder (Dave) using them for something or other in my T1 thread (I think), and they have a very comprehensive/education/materials site.

SO, high temperature? How high is high? I'm thinking 110 degrees C is enough?

Highest Temperature Range
+140° to +175° F (+60° to +79.4° C)
+176° to +200° F (+80° to +93.3° C)
+201° to +230° F (+93.8° to +110° C)
Up to +302° F (+150° C)
Up to +400° F (+204.4° C)
Up to +482° F (+250° C)
Up to +842° F (+450° C)
Up to +1832° F (+1000° C)


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#93: Post by orphanespresso »

As far as all the amp ratings....you can go to a gauge/amp chart to see what gauge wire to use for a certain rating. 10 gauge power cord (about the same as used on a fairly big welder) looks a bit ungainly but if you get a good quality wire it is rubber coated an nice and flexible. Make your own using a separate plug as I said. Yes, PTFE is good has you don't have to worry about the temp rating since it is pretty high...the extreme high stuff is too pricey and overkill but you could get 25 feet of 10 gauge to do the whole thing and never worry about it. 25 feet is not a lot as it turns out.

The types of switches can be confusing...for example, most home machines use a double pole double throw, which means that both the hot and neutral wire enter on one side of the switch and each is turned on/off when you use the switch. Once again a wiring diagram is a useful item here....think of it this way....the hot wire will enter the switch and once you turn the switch ON the current will go to the pstat and then to the element. The element is the LOAD in the circuit. The other side of the load, or the exit from the heating element is now all on the neutral side of the circuit. If you have a thermostatic safety switch it should be on the HOT side of the circuit along with the pstat and any other switches. You do not have to use different colored wires but I personally like to use one color for the hot side of the circuit and one for the neutral side of the circuit since this helps focus the mind.

Not wiring the gicar into the circuit will simplify the affair but if you wire it in it is always on, so you use a bridge on hot side of the switch that bypasses the pstat and then returns to the neutral side of the circuit at any point of convenience. Wiring up a bare machine is actually one of the more enjoyable aspects of the project.

phillip canuck

#94: Post by phillip canuck »

The espresso machine gods were smiling on me yesterday. I checked craigslist and found the same model, same colour Z9 as mine being offered for parts at $150. As fast as my fingers could type I sent out an email and a few hours later I had the boxes in hand. I was most excited for the intact wiring (!!!) that I can now use as a model for my 1983 Z9. I've since found out that this is a 1980 model and it packs a few goodies. Little goodies such as a decent 30A pstat, metal collars on the groups (mine are plastic) and a fully functioning manual fill (my base is broken and cannot be ordered). However, the best little egg found was the the gas hook-up! Yeah! I don't know if everything is there, but photos are below if someone would like to tell me before I check the diagrams. This Z9 was functioning before the disassembly, but it is not believed that the gas was connected.

I'm not sure what I'll do with this "new" Z9 after I cannibalize her for parts. I just may rebuild a second. I'm not sure. What I am sure of is that my original Z9 just got put on the fast track to being finished.

Doug, and many others: Know that your electrical advice has not been wasted. It's not going to be a simple transfer of wiring harnesses. Not to mention that I like Doug's advice of setting a DPDT switch to have a low and high setting for the boiler. Rest assured, I will still have a few electrical questions.

The burner is quite rusted. I'm not sure if that can be easily ($$) replaced, but I'll do my best to clean it up.

My first question on the gas/propane option: the igniter, below, throws a spark (great). However, in what is currently a mystery for me, if I hold the burner and depress the switch to ignite the spark - I get a small electrical charge in my hand. I'm not even sure how that spark is being created. I'd like to take it apart, but I think I'll investigate a bit more first.





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#95: Post by orphanespresso »

Some people have all the luck!

the piezo ignitor (sparker) is the easiest part to replace and likely you can even do without it and use a long reach butane lighter (one less thing to go wrong). It looks like the gas system is complete but a little cobbled together...you have the initial valve and the pressure regulator that responds to boiler pressure (hopefully). The thermocouple seems integral to the piezo but can be done real simply separate..it is the burner that is important as the valves tubes and other parts can be put together.

The attractive thing about a gas system, apart from the possibility of carbon monoxide poisoning, which may or may not be an issue, is that it operates with basically no dead band like on a pstat system....it just cruises along and if you have it set a 1 bar then it stays at one bar and the flames get larger and smaller to maintain that pressure. It is almost magical, but as I said, may have certain drawbacks when used in a closed room for any period of time. My last and keeper project is a Faema Urania which never had electrical installed, just gas and I am determined to keep it as a gas only....we'll see how it works out, danger-wise.

phillip canuck

#96: Post by phillip canuck »

And so it continues...(I have started and completed a few other machines in the span of this rebuild)

Electrical issues all but completed (need to buy a new plug), now there is just a couple of items.

Gas anatomy - What do I have here, exactly?

Here is what I think I know:

A thermocouple
B start the gas flow
C ??
D is the piezo
E ??
F & G control flame/regulator?
H and I fit together
J ??

Of a mystery to me is exactly where A,C,E and J connect on my machine. Given that this kit came from another Z9 I suppose I could be missing some male/female parts on my Z9. I've checked all the diagrams, photos and manuals from Rancilio. However, my gas burner and kit are different from what I've seen.


Second issues..

X is for water in??
Y is this over pressure valve that dumps to the drip tray?



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#97: Post by SAS »

My two cents:

'E' or 'J' goes to the pressurestat. Which ever doesn't, goes to the gas line. I vote for 'J to Pstat.

'A' could be your thermal protection and shuts down the whole system if overheated with 'B' being your adjust for what temperature 'A' controlls the system.

'C' might go to 'E' with the end of the stainless flex pipe connected to your gas source.

Good luck!

I edited the above based on Clint's post.
LMWDP #280
Running on fumes.

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Clint Orchuk

#98: Post by Clint Orchuk »

C connects to E. J connects to an elbow on the bottom of the sight glass. It regulates the height of the flames. None of it connects to the pressurestat because the pressurestat isn't used on a gas system. F and G are used to set the limits of the flames, much like a pressurestat. There are some photos in my old thread about rebuilding the two group Astoria that might help.


#99: Post by zubinpatrick »

"None of it connects to the pressurestat because the pressurestat isn't used on a gas system."
just a little clarification for those just getting up to speed, the electrical pressure stat does not gets used on the gas system. If Clint has I.d.ed them correctly (and I believe he has) F and G are the pressure stat for the gas system.

phillip canuck

#100: Post by phillip canuck »

Thanks for the help Clint, SAS and zubinpatrick.

First, to answer one of my own questions - Y is for water and X goes to a "hidden" pipe that I just failed miserably to see until I wasn't looking for it.

As for the gas... funny the things you find on HB...Propane Conversion Astoria 2 Group Lever

Though it still doesn't help me with...
Clint Orchuk wrote:C connects to E. J connects to an elbow on the bottom of the sight glass.
There is no elbow on the bottom of my sight glass. I don't know if I'm just missing the elbow or there is a different set-up for different machines, like mine.

Does anyone agree with me that it seems A (thermocouple?) sits in the flames?