Rancilio Silvia intermittently not heating

[Roberto]

I have a Silvia about 4 years old. Recently it has developed an intermittent problem. The heating light doesn't come on and it doesn't heat. However, it does have power through the switch.

Jostling it and banging it is somewhat effective in restoring the heat.

To add a potential red flag. I only descale it about 1x per year. This is probably my red herring issue so I don't need a lot of advice regarding descaling it more often.

What do you think it is?

My guesses are.

A. Defective thermostat

B. Defective switch.

C. Loose connection (Note I did check that one out and the spade connections all appeared to be as tight as a frog's behind).

Any advice is appreciated.

Thanks,

Roberto

[HB]

Assuming you are electrically inclined (and evidently you are), it would be easy to bypass A or B the next time it happens.

[Randy G.]

4 years old? original brew thermostat? That's probably it.
If you have the failure occur again, flip on the steam switch. if it heats then, it is 99.9% most likely the brew thermostat.

[JimG]

Randy's suggestion to try the steam switch should confirm or eliminate the brew stat as the culprit.

If the question still isn't answered, though, I'd add the following to the list of suspects:

D. Failing heating element

I think you can eliminate the safety thermostat as the bad actor. When this is tripped, the heater light still comes on, even though there is no current through the heater.

Finally, since it is relatively common for a bad heater coil to short to the boiler, I'd recommend operating the machine on a GFCI-protected outlet. This is always a good idea, but especially important when you are seeing odd behavior that could be related to the heater circuit.

Jim

[Roberto]

It was the Brew Thermostat. Thank you for your suggestions.