Heating element? Rancilio Silvia makes GFCI outlet trip with power switch flipped on

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

#1: Post by blacktshirt »

Hi All -

I'm brand new to the forum but have been reading up on others experiencing GFCI tripping issues with their Rancilio Silvia. I have a PID installed. At first I am suspecting heating element, but after running some tests, I am not sure. Can you help me troubleshoot?

Here's what I experienced on my machine (V3 boiler):
This morning I made a milk drink, and flipped back to coffee mode, but forgot to fill the boiler. I left it in this state for about ~7 hours at 215 degrees. When I returned, I pulled a shot with no H2O in the boiler, the pump filled the boiler (I cursed a bit because i realized I had forgotten to fill the boiler), and shot was extracted. While cleaning the portafilter using water switch and the pump going, the GFCI outlet tripped and the unit shut off (big kicking-myself moment).

Replicating the issue
The unit now trips the GFCI outlet as soon as I flip the power switch on. I have run a hair dryer on the GFCI outlet I normally use and runs fine. I have plugged in 3x different GFCI outlets with same result.

Tests I've Run
  • I disconnected both heating element positive and negative terminals from the power switch, and success - there is no trip of the GFCI outlet. Lights go on, PID goes on and stays on.
  • With my voltmeter, there is no continuity from either element terminal to the boiler casing which tells me there isn't a fault there
  • There is continuity between plus and minus terminals on heating element
  • The Ohms reading is 16.9 between element terminals, which I have been reading is normal
  • I have not seen any obvious burnt out wiring or rubbing on wiring that some may have experienced causing a grounding
So in closing, the fact that the GFCI outlet is not immediately tripped after the heating element terminals disconnected points me to the fact that the element is the issue. That said, with the tests I've run specifically on the element, I'm not certain.

Thanks so much for your help in advance!

-Alex

User avatar
Jake_G
Team HB

#2: Post by Jake_G »

blacktshirt wrote:With my voltmeter, there is no continuity from either element terminal to the boiler casing which tells me there isn't a fault there
Hey Alex,

Welcome to HB.

This statement is not necessarily foolproof unless you are using a megger or hi pot machine to do the test. While getting continuity between a element terminal and the boiler is a sure fire test to prove the element is bad, it is unfortunately not a sure fire statement that you do not have a short to ground just because you can't measure it with a multimeter.

GFCI outlets only need a few mA of imbalance between the line and neutral to trip them. It is assumed that whatever imbalance is leakage to ground, which is why the GFCI trips. Better to shut it down than risk the stray current passing through the machine operator. While it is a bummer, I strongly suggest you refrain from plugging in the machine until you replace the heating element. The GFCI should protect you from electrical shock, but I would not risk it.

Cheers!

- Jake

Nunas
Supporter ♡

#3: Post by Nunas »

You could pull the element or use a borescope to give it a physical inspection. What usually happens in situations like yours is the outer sheath of the element ruptures due to overheating. This does not always result in the element burning out. Then when you put water in, it enters the fissure and saturates the insulating material, providing a high impedance path to ground (as noted you can't easily measure this). Usually, you can see this damage as a swelling on the element.

There is an old-fashioned way to test these. This is not safe for those who are not familiar with electricity. You make up an electrical box with a socket (e.g., standard duplex receptacle.) Inside, you break the little jumpers between the two sockets. You wire the two sockets in series, with an extension cord leading out with a standard plug on it. Now, no current will flow unless you have something plugged into both sockets.

Empty your boiler, plug the Silvia into one socket. Plug another resistive device with similar power requirements into the other socket. For a typical espresso machine, an electric iron would do. Now turn on both devices and leave them on. Plug the series-box into a non-GFCI outlet. Don't touch any metal surface and do not leave this unattended! After several hours, unplug the device and then plug the Silvia into a GFCI outlet and switch it on briefly. Fill with water then turn it on again. An element with a broken shell will work when dry but then will trip the GFCI when wet (the water goes back into the heater). You now know exactly, if anything, is wrong with the heater.

How this works: You can't just plug in the Silvia and let it dry out on full mains power, as that's what caused the problem in the first place. By placing two devices with similar load requirements, the voltage across each will be roughly half of the mains voltage. Both devices will heat up very slowly and usually not to their maximum extent. The heat in the Silvia will dry out the insulation inside the heater.

This is an old-fashioned appliance repairman's test, it's not a cure!. Years ago, they would have tried to repair an element like this and put it back in service. These days, it isn't worth the time and they just replace. All this said, odds are your element is shot and you might take a chance and simply replace it if you wish to keep your Silvia. That's what I'd do.

User avatar
civ

#4: Post by civ »

Hello:
Nunas wrote: ... odds are your element is shot ...
+1
Unfortunately for our new member, you're right on the dot.

A boiler's element tripping a GFCI protected circuit once it starts to heat up is quite common and not only due to overheating (eg: empty boiler) as deposits can also take their toll on the outer sheath of the element, as this photo of the one I replaced in one of my 1970 Pavonis can attest:

Image

Unless the problem is due to cracked terminal insulation, which could be fixed, there's not much to be done.
You'd have to pull the element to clean it up and inspect thoroughly and if nothing is evident, bake, seal the terminals with a glyptal based resin and then reassemble to test, hoping that was the problem.

Fortunately a replacement element for a Rancilio Silvia is easy to come by and not too expensive to replace.

CIV

JRising

#5: Post by JRising »

blacktshirt wrote:Hi All -
So in closing, the fact that the GFCI outlet is not immediately tripped after the heating element terminals disconnected points me to the fact that the element is the issue. That said, with the tests I've run specifically on the element, I'm not certain.
-Alex
Agreed that you can't be "Certain", but based on what you've done so far, yes. The filament inside the heating element is no longer safely insulated from the copper pipe that holds the filament and insulation inside. It can't heat without shorting to the wall.

Depending on the age of your Silvia, you may be able to replace just the element,
https://www.espressoplanet.com/Rancilio ... asket.html
or the whole upper boiler (If your Silvia is older and has a different element) with the new upper boiler with the element included.
https://www.espressoplanet.com/Rancilio ... 5636).html

blacktshirt

#6: Post by blacktshirt »

Thanks to all for your replies!
civ wrote: Unless the problem is due to cracked terminal insulation, which could be fixed, there's not much to be done.
You'd have to pull the element to clean it up and inspect thoroughly and if nothing is evident, bake, seal the terminals with a glyptal based resin and then reassemble to test, hoping that was the problem.
What's interesting is I DO see cracked terminal insulation - but I think this is pre-existing, as the insulation pieces are baked into the resin that's visible in the photos below. When I first opened the unit I immediately saw the cracked insulation, but since the pieces are immovable/glued into the resin and the unit had been functioning fine up until yesterday I assumed it was fine. I'm guessing this occurred when my machine was modded (it's a 2006 year with a V3 boiler).
Image
Image

Terminal insulation could be a red herring, since I know the exact events that lead up to the failure. But maybe the previous resin-job finally failed? In either case - thanks for another insight. It could really be worth a shot to try the resin baking instructions first before replacing the element.

If it IS the element - and all signs are pointing that way, would anyone share a good HOW-TO on replacing the V3 version? I think it's supposed to be a lot easier than some of the earlier versions. Thanks to @jrising for the helpful ordering link.


Again, appreciate the help with another project while quarantined at home. Thanks for the warm welcome and hope all stay safe & well.


Cheers,
-Alex

JRising

#7: Post by JRising »

That little bit of cracked ceramic outside the boiler isn't much of an issue. Might have happened when something major blew inside the boiler, but that external bit is nothing.

And good news. You have the V3 boiler so the fix is easy.
In addition to the new element, buy a new boiler seal o-ring as well. Might as well replace it since you have top open a boiler.
https://www.espressoplanet.com/Rancilio ... asket.html
https://www.espressoplanet.com/Rancilio ... asket.html

Step by step as if I were doing it.
Take out the 4 screws from the top. Remove the reservoir and remove the top. (I think you already did for the picture).

Loosen the 2 philips screws that hold the back(Stainless) To the frame (Black) near the top-middle of the machine, you'll see them looking from in front of the machine, near the top of the black frame in the middle of the machine.
Look down the inside of the back of the machine where the reservoir usually sits, see the notch cut out at the bottom middle of the back? There's a screw in that notch that you can get with a long philips screwdriver, loosen it.

With all those screws loose, you can pull the stainless back panel to widen it and have it clear the frame as you pull it back and out at the bottom then lift it.

Take another picture or 2 that captures all of the wiring connections well. Just in case, ya know.
Mark each of the wires with a Sharpie that goes to a component on the upper boiler. Use whatever markings you like.
(I use E for Element, H for High (Steam Thermostat), L for Low (Brew Thermostat), and B for Break (Safety Thermostat).
Pull all wires off of the thermostats and element.
Use a crescent wrench (I believe it's a 17mm) or a small adjustable wrench to loosen each end, just a little turn each, of that copper tube between boiler and steam valve. Once both ends are loose and you're sure you're not torquing up and twisting the copper tube, unscrew both ends and take the copper tube out.
Now, at the bottom back of the machine, you'll want to use a small adjustable wrench to hold the elbow at the pump outlet and (I think 12mm) crescent wrench to unscrew the braided hose's fitting from that elbow.
Now you'll need an allen key, I believe 4mm, for the 6 screws around the middle of the boiler. If you have a nice, long, T-Handled Allen key you'll want it.
Loosen each of the 6 screws just a little, then back them all out about 4 full rotations. The boiler probably won't start leaking yet, the 2 halves will be stuck together by the o-ring and any scale that's built up in there.
Now, take all loose items away from the machine, grill, drip tray, etc. Empty the kitchen sink.
Coil the cord up to keep it tidy, carry the machine to the sink and turn it upside down over the sink. If the boiler pops itself open, then air will rush in around the middle and the water will drain out through the hole where the copper pipe used to connect. So long as the calcium isn't bad it should drain in about 15-20 seconds. If the boiler doesn't pop open around the middle where you loosened the 6 bolts, reach in and give the boiler a jiggle. In the worst case scenario, one person can hold the machine upside down over the sink while another person gives the boiler a smack with a little hammer.
The small amount of water that splashes on the outside of the side-thermostat isn't a problem, once you stand the machine back upright, wipe up the splashes with a paper towel or dish rag.
Take the 6 bolts the rest of the way out. Lift the upper boiler off of the lower boiler. Inspect both.

This is the point where you decide if you want to give the upper boiler an immersion descaling, just do a mild descale of the whole machine or if it doesn't need descaling at all. If it needs it, clean what you easily can now while it's all open to the world.
Now, take the big nut (Outside top of boiler)off of the old element, put the new element in and tighten it with the big nut. Throw away the old red o-ring if you bought the replacement. Reassemble in reverse order of everything here.
Note: When reconnecting the copper pipe from boiler to steam valve, hold the pipe so that the fitting is nicely centered in it's seat, then tighten the threading with just your fingers to keep it positioned. Then the same for the other end. Lastly, tighten these two ends gently. They are compression fittings, they seal just by having the soft copper pressed together at that angle, they're not threaded steel pipes that need to be torqued together by a gorilla. After finger-tight, less than 60 degrees (One face of the hexagonal nut) should be more than enough.

REMEMBER: Your machine now has no water in the boiler. It is best to leave 1 of the element connections disconnected after connecting all of the other wires. Then, before putting the top back on the machine, open the steam tap plug the machine in, turn it on, put a mug under the steam wand, turn on the pump switch and let it fill the boiler until the water runs out the steam wand. Shut off the pump switch, close the steam wand, UNPLUG THE MACHINE again before touching the element wire to connect the second electrical connection, then plug it in again and flip on the pump switch to run the machine at maximum pressure. You should see water flowing back to reservoir through the second hose because there's nowhere else for it to go with all the valves closed. So long as you don't see water leaking anywhere, you've done a good job. You deserve a nice espresso.

User avatar
civ

#8: Post by civ »

Hello:
blacktshirt wrote: ... see cracked terminal insulation ...
What you are seeing is a cracked ceramic insulator.
What I have referred to is the red glyptal stuff around it that, if cracked far enough, would leave an open route for dampness to seep into the heating element. Looked at from here, it does not seem to be the case.
blacktshirt wrote: ... the previous resin-job finally failed?
Doubt it, this looks like a well done OEM heating element job.
blacktshirt wrote: ... worth a shot to try the resin baking instructions first before replacing the element.
The boiler has to be unmounted, cracked and the heating element has to be taken out anyway.
Once out, you will be able to clean it up and thoroughly inspect the coils for damage.

My money is on this being the cause of the problem:
... flipped back to coffee mode, but forgot to fill the boiler. I left it in this state for about ~7 hours ...
This model is different as the two element posts are inside one nut/hole/assembly vis-a-vis the earlier models that have one nut/hole per post.
In terms of difficulty, I see it as the same.
blacktshirt wrote: ... a good HOW-TO on replacing the V3 version?
Now comes the important question: how technically inclined and how comfortable are you taking apart electrical appliances?
Because,i ndependently of the specifics of the problem at hand, it is important that you understand some basics.

The main one is taking into account that electricity and water do not mix well.

Any maintenance should be done with the machine unplugged and any electrical repairs/mods should be done by/looked at/supervised by someone who understands how these machines work and knows about how to work with electrical appliances.

If you do not have some basic electrical experience ie: you are not an engineer but you know how to repair a toaster or a vacuum cleaner, you may be better off getting a home appliance tech/electrician/knowledgeable friend to help you sort this out while at it.

That way you will also learn a few things along the way.

That said, check the web and HB for a schematic of how the Silvia is wired and take lotsa photos of everything before you start taking things apart.
HB is a treasure trove of information and the Silvia has had a huge amount of owners among its members.

The Resources section and the search function will be of great help.

Above all, don't rush things: Prudence and Patience will be you best of friends. =-)

Cheers,

CIV

blacktshirt

#9: Post by blacktshirt »

JRising wrote:And good news. You have the V3 boiler so the fix is easy.
Thank you for the incredibly detailed and thorough instructions - I'll be ordering a new element and boiler o-ring today.
civ wrote: Above all, don't rush things: Prudence and Patience will be you best of friends. =-)
This is definitely my plan. :D I'll try and keep a steady head. Thanks for the support.


I will keep you posted on how it all went!

Cheers
-Alex

Nunas
Supporter ♡

#10: Post by Nunas »

Alex,
When you replace the heater, pay close attention to the two terminals. I was looking again at the photos you posted and just noticed the terminal on the brown wire shows signs of overheating (the melted plastic). This is not usually caused by leaving the boiler run dry. It is usually caused by a bad terminal connection or corrosion. When you put the new heater in, you must make sure that the terminals are clean and tight. If they are not, a small resistance happens. This resistance is like having another heater (formed by the terminal connection). The melted plastic is no biggie, but if the female connector inside looks damaged (discoloured, corroded or sprung open), then you need to replace it. Don't just squeeze it shut with pliers and hope it will make good contact.
Maurice