Pressure stat for Oscar Nuova Simonelli

[poddypod Junior Member Find all posts View Profile Close poddypod]

Hi All, descaling my Oscar with Cafetto vanish & then pulatte, (because it was "skunked" i.e. milk was sucked up into the boiler) I reckon I have done a mischief to the snap action switch or the Pressurestat because now the machine will not switch off heating and therefore pressuring. I have been googling all evening and in desperation, I am turning to anyone for help. I want to source the switch first and see if that does the trick. Anyone give me any hints on where to go/ask?? I am Sydney. I took a photo of the little beggar. I'll see if I can upload. Much obliged.

[noidle22 Senior Member Find all posts View Profile Close noidle22]

The Cherry D45 series are the standard on Mater pressurestats, not sure what brand that one is. They're all the same size anyway.

You can buy them from RS Components, part number 159-4534. $4.67 with free next day delivery.

[poddypod Junior Member Find all posts View Profile Close poddypod]

Thanks Noidle, I am amazed...and very grateful.

[noidle22 Senior Member Find all posts View Profile Close noidle22]

No problem.

If the switch doesn't fix it, another thing to check particularly as the fault happened after descaling, is that some scale or other debris has gotten stuck in the pressurestat tube or diaphragm of the pressurestat itself.
You would need to remove the pressurestat from it's fitting and checked in them for any signs of scale.

If this happened, the pressurestat won't be getting a correct boiler pressure reading and may not turn off when it should causing it to keep heating.

[poddypod Junior Member Find all posts View Profile Close poddypod]

No problem.

If the switch doesn't fix it, another thing to check particularly as the fault happened after descaling, is that some scale or other debris has gotten stuck in the pressurestat tube or diaphragm of the pressurestat itself.
You would need to remove the pressurestat from it's fitting and checked in them for any signs of scale.

If this happened, the pressurestat won't be getting a correct boiler pressure reading and may not turn off when it should causing it to keep heating.

I reckon it was shorted with moisture because it was just as I filled the boiler (over-filled) and water came through the valve, and the circuit breaker was tripped. But thanks for that tip - as they say in medicine "you are allowed 2 problems"

[poddypod Junior Member Find all posts View Profile Close poddypod]

Just a post script. I put my order in this morning and got home to find the switch delivered. Under $5 & problem solved! Just put it in - works a treat!

[poddypod Junior Member Find all posts View Profile Close poddypod]

Hey Noodle, just a post script....you were dead right about needing to replace the pressure stat. After replacing the switch, the machine began running hot fairly regularly. The pressure valve would occasionally blow and my poor little terrier was seriously developing an anxiety disorder (machine must have been emitting a supersonic "dog whistle" because whenever th machine was on he would be at my heels and SHIVERING ) . Eventually the parts I'd ordered came in and I changed the pressure stat and all was remedied. ALSO for quite some time, I had been not satisfied with espresso I was producing and I was mucking with the grind and the tamp to no avail. Now I am back on top !!! Happy wife - happy life. Thanks for your advice. Without it I probably would be spending a fortune on a pet psych and worse putting up with mediocrity. Pod

[poddypod Junior Member Find all posts View Profile Close poddypod]

Sorry Noidle22, I need laser surgery for myopia I have only just realised my mistake reading your member name. Sincere apologies. Pod