Calibrating Rancilio Nancy

Need help with equipment usage or want to share your latest discovery?
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Postby theCoffer » Wed Mar 11, 2009 3:28 am

Hello everyone, this is my first post in this amazing forum.
I have recently bought an old Rancilio Nancy (probably from the 90's). The machine seem to work fine, but nonetheless I have not been able to get 1 decent shot out of it.
My grinder is a Rancilio Rocky that matches the colours of the Nancy (was bought together with the machine), and seems to be grinding ok.


Here is the pump:


Here is the Boiler - Watlow - OPV:


And here is the detailer view of the OPV:


And here the thermostats:


Ok, so what I would love is if someone that knows this machine could help calibrating the thermostat and the brew pressure (through the OPV). But, to tell the truth I don't know exactly how to do it. The water seems to be coming out too hot because too much water vapor comes out of the shower when I turn on the switch. And the pressure seems to be too high (but I don't know how to verify it because I don't know what pump it is to check the flow in 30 seconds). Well, any help at all will be treasured.

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Postby HB » Wed Mar 11, 2009 3:41 am

theCoffer wrote:Ok, so what I would love is if someone that knows this machine could help calibrating the thermostat and the brew pressure (through the OPV).

It looks like the same over-pressure valve as an older Rancilio Silvia; if so, see this thread. Unfortunately the old OPVs were not adjustable unless you shimmed it. As for brew temperature, well, there is no calibration, there's only the time-honored kludge referred to as temperature surfing. Mark demonstrates his flush-n-go technique in this video:

Assuming your machine and its more popular sister Silvia share components, you will find gigabytes of discussions online. The FAQs and Favorites lists a sample under 'Silvia and Rocky' as well as recommended reading. And I'm sure that if Randy G. reads your post, he'll point you to his site, including the guide whose name is remarkably similar to one published on this site. To save him time, here you go:

Espresso! My Espresso! wrote:12 - HOME BARISTA'S GUIDE TO MAKING QUALITY ESPRESSO - If you are beginning to make espresso, this guide will be invaluable in helping to avoid many pitfalls and will help build good habits right from the start. If you are having problems with your espresso, the solution is probably in this very complete guide to making espresso.
Dan Kehn

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Postby caffeina » Mon Jan 18, 2010 9:34 am

HI, i've a nancy too and the problem of vapor during shot is created by bad boiler water refill.
When it manifest the problem is impossible to have a good shot. Check eventually filters and play shot button until boiler is empty and recharged. Prefer make this operation with boiler cold.

Nancy can made fantastic espressos!

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Postby denniskeating » Mon Jan 18, 2010 3:58 pm

Machines produced before year 2000, or 2001 were useing a 105 C brew thermostat. You can buy a 100 C replacement. About $15 US.

Your brew pressure is probably 11 to 13 bars. You have to shim the OPV, or install the new adjustable model.
It is $45 US. The bad news is the cover won't fit back on the machine unless you modify it. They sell extra washers for shims, too.


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Postby sweaner » Mon Jan 18, 2010 4:56 pm

If you haven't done so, replace the burrs on the grinder as well.
LMWDP #248

Man does not live by coffee alone...we need beer too.