Hello everybody,new to the form. I've been lurking and learning in back ground for the last year and what an education it has been...Thank you all.

Well I just got a cremina off eBay and when I plugged it in it blew the GFCI outlet.
I traced it down the heating element,and then found an old thread on the subject.
That took me to OE's tech tips. I tested the element as shown and here is what I
got.

Resistance from contact to contact is 12.3 but will waver to 12.2 a couple of times
over a 20 sec period.
OE says that contact to contact resistance should be steady. Would that be considered steady???

Resistance from contact to base reads 0. That is GOOD.

I did send an email to OE, but since it's a weekend I thought I'd see what others think.

Wavering of 1/10 ohm is meaningless. Zero ohms to ground is a ground or a great connection, if that is what is wanted. Or did you mean infinite ohms? It should be a high number to indicate proper insulation. Your GFI detected current to ground so opened the circuit.
KDM

I wouldn't worry about a slight variation in the resistance reading.

However, it takes only a tiny leak to earth (ground) to trip a typical RCD/GFI. On the 230v supply we use in Europe, they are generally set at 30 milliamps, I don't know what is typical where you live. Whether you actually have a tiny short depends on how sensitive you set the meter when taking that reading. If you took it at a low sensitivity, it may show infinite, but is not detecting a small leak. At a very high sensitivity - say 200k ohms scale, it should still read infinite. If it doesn't, there is a problem, but it may be fixable.

Quite often, elements that have not been used for some time can absorb moisture - just enough to cause problems. In the (bad ?) old days, the solution was to plug it into a non-protected outlet and let it heat up. The heating will normally expel the moisture and fix it. I'm NOT recommending you do that, but it is often the case that if you can get the element heated up in some way, it will cure the problem. Removing it, gentle heating over a low gas flame etc. might do the trick.

I had a small radiant heater from a cona machine which had this problem. Placing it face down on an identical heater, and switching that one on until they both got red hot (with a few spits and pops happening) fixed it.

Unless you paid a few thousand for your ammeter and it reads to the /100th ohm, the flicker in the final digit is normal.

12.3 ohms is roughly 975 watts nominal (at 110V), so your element is good.

About 2/3 of the metal cased machines I've ever owned regularly blew the GFCI, since these things are designed to make sure any stray gnats in the machine are safe. You need to make sure no wires are touching the case, even where insulated, and the connectors are all ultra-tight. Mostly, it's loud cursing and using a hairdryer to make sure everything is Sahara dry that does the trick.

As duke-one noted, but may not have made it clear enough, zero ohms from element to ground indicates a SHORT CIRCUIT.

However it is entirely possible you meant infinite ohms, which would be expected from a working machine (no circuit between element and case)

Which is it? If it is indeed zero, then you need to figure out where the short is.

Say All: Lets get some terms down:
A short circuit is when power goes from hot to hot or hot to neutral without a load in-between.
A ground or ground fault is when any line or neutral (other then where proper) goes to ground.
An overload is when more power then desired or expected is taken from a circuit or part of one.
An arcing fault is when an arc is drawn and maintained anywhere it is not wanted. These are very destructive because without special protective devices they can keep going and really tear up equipment, not to mention burn down buildings. They don't draw enough current to trip a breaker or blow a fuse.
So a heating element that is leaking to ground is a grounded element, not a short.
KDM

Fair enough.
However you slice it, there appears to be an undesired connection between the heating element and the case, which will not necessarily lead to a short circuit, depending on how the unit is grounded and/or wired, but which may lead to an unsafe situation.

It is good that the unit was plugged into a ground-fault-circuit interruptor because otherwise you might not have noticed the problem until you plugged it into a mis-wired outle (hot and neutral reversed) or if the unit has an ungrounded and unpolarized plug, if you plugged it in backwards (assuming a 120VAC circuit - on 240VAC, things get different)

But you're right, I should be more careful with terminology.

Hey everyone,thanks for the reply's. It was just the encouragement I needed to keep looking. it's been a while since I've really had to use a multimeter for much more then checking an electrical socket to see if it was working or not. Here's what did and found out.
1. Took ground connection apart and cleaned off corrosion. Checked with meter and get .4 ohms from gourd prong on plug to ground on boiler base plate. That seems good to me. But as Duke-one & allon pointed out,
0 ohms from element to ground indicates a short circuit. If I did this right? I went from ground on boiler to
element connection and got 0 ohms. Bad???

2. Inspected all connections for signs of chafing and wrapped with electrical tape. I have the case off and no wires are touching any part of machine and all connections are tight.

3. Bypassed heating element with multimeter and got 120V and switch light & pilot light all worked. GFI
didn't pop.

I keep thinking heating element???

Thanks for the help everyone.

Unplug machine.
Disconnect heating element wires.
Measure resistance between each heating element terminal and a nice copper bit of boiler or fitting on boiler.

If you get anything less than infinite, you've got a problem with the element.

Measure resistance between element terminals. Apply ohms law to calculate what you expect the wattage to be. Make sure it jibes.

While the resistance wire in the heating element may be good, a tiny pinhole in the outer surface of the heating element can allow water in to the element which will easily trigger a ground fault that would not show up on your meter. And has been stated (which I did not know) the element could have absorbed moisture causing the same outcome. So if it doesn't trip the GFCI when the element is disconnected, and it does trip when it is, it pretty much narrows it down...