Another Rancilio Epoca Rebuild

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
wolfpv

#1: Post by wolfpv »

I just overpaid for a Rancilio Epoca single group machine, and have torn it apart. Lots of issues. Mostly I think I can get everything back to operational, but I broke the capillary on the "Bipoler Thermostat", aka "Save Heating Element". I've bought a replacement, but I have a few questions about it:
  • The previous thread referred to a description on "Espresso Parts, saying specifically
    "When installing, it is important to make sure the capillary does not come in contact with the heating element after the high limit is installed. It should be positioned so that the capillary tube is about 8" down from the boiler top." (https://www.espressoparts.com/parts/com ... thermostat
  • However, my machine has the capillary intentionally wrapped along the bottom ring of the element - exactly the opposite of the directions on "Espresso Parts"
  • Does anyone have any idea why this discrepancy exists? It would seem to me that if it cuts out at 165C (329F) it would be pretty useless sitting out away from the element
  • Any suggestions as to where I can obtain a replacement for the Teflon or Delrin seal?

In addition to the issues with this temperature device, I'm also wondering if anybody knows the Part number and a source for the little washer which goes between the boiler and the group casting:

Thanks for your help!

JRising
Team HB

#2: Post by JRising »

Your pics puzzle me. I've never seen anything "clipped" to the element like that. The well in which the capillary and tip reside shouldn't be touching the element. It should be as close to vertical as possible without contacting anything except where it screws into the cap. Everyone I've seen is a little bent, but nearly vertical, like in the diagram.


Rancilio calls that o-ring 36402001


You could contact https://support.ranciliogroup.com/en-us/ for parts.

I don't see anything about the silicone seal around the capillary for the hi-Limit, sorry. I've replaced 2 or 3 thermostats over the years and always just re-used the existing one. It doesn't really seal anything other than keeping the thermal paste in place.

wolfpv (original poster)

#3: Post by wolfpv (original poster) »

JRising - thanks for the thoughtful reply. I notice that your drawing is of the newer over-temp device, which is in a tube. What I can't figure out is why a device with a trigger temperature of 165C (329F) would be sitting out in the water well away from the element. It would simply never trigger, regardless of whether the boiler was a "runaway". It makes more sense that it would be close to the element - as it was in my machine. Nevertheless, yours is the same answer I got from Espresso Parts, and they seem to have put some effort into coming up with an answer...though they admitted it didn't make any sense!

JRising
Team HB

#4: Post by JRising »

wolfpv wrote:It makes more sense that it would be close to the element - as it was in my machine. Nevertheless, yours is the same answer I got from Espresso Parts, and they seem to have put some effort into coming up with an answer...though they admitted it didn't make any sense!
It's not supposed to ever trigger. It's for when things go horribly wrong and the shorted out element is still heating the water faster than the safety valve is blowing it out. It's like airbags in a car. You hope it works but never has to.

The element is getting up WAY higher than 165C when it's on, the filament inside is probably white hot, the casing glows a little bit orange if you test an element in the sink to see if it is heating evenly or has "hot spots". If you only get one extreme spot of heat on an element, it's about to burn out at that spot. In order to glow dull-orange while submerged, it's hotter than 165C.

Sorry about my dumb answer for the wrong era of Epoca... I didn't know there was a different, older sort. Good luck with the search, you may want to ask RanciliogroupNA Support, maybe they'll have someone older than me that knows.

sketcher88

#5: Post by sketcher88 »

In your first photo, you ask "is this really neccesary" and I think that's a breaker, so I'd keep it, assuming the red part is a reset. I had an old S-20 Midi and I recognize plenty of similarities. That teflon plug you're seeking, I had the same question, and for the same reasons (I broke this fragile little probe during my rebuild) but I bit the bullet and just bought a new one, and set it into the thermowell without a plug.

Also, about those copper bands, I had those in my old heating element too and I wouldn't use that to tie to the thermowell at all, so just keep them separated. It's not like there's going to be a ton of turbulence or flow through the boiler so this was maybe always a bit overkill. If only they'd put more robustness into the thermowell/temperature probe assembly...