Hey folks,

I have a Rancilio Silvia V3 with an Auber PID. I noticed over the past 3 weeks that steam is bubbling through the overflow tube/return line in the water reservoir when I have the steam function turned on. This does not happen while pulling regular shots. For what it's worth, the machine is 2 years and 1 month old so warranty is out of the question.

I clean my machine thoroughly once a month and recently rebuilt the steam wand with the new gasket/o-rings. There are no leaks of any sort. I'm getting good shots as usual. I have NOT yet made adjustments to the over pressure valve. The 3-way valve works as usual (or at least I think so anyway.) Long shot here but any possibility my pump is going bad?

Please see the following Youtube video below. I apologize for the poor quality but you can see the steam bubbling/gurgling through the overflow tube. You may need to turn up your volume. Any comments / suggestions appreciated. Thank you!

Mike

Most likely your OPV gasket is cooked,

I've seen quite a bit of them recently in for repairs and most of them had PID installed,

I do not say is the PID fault but I'm saying I noticing it happening more on machine send in for repairs that have pid,
perhaps because of the PID customers keeps them on more then customers without?

Thanks Stefano. You're right about keeping the machine on. I leave it on a timer 8 hours a day and is used at least 4 to 6 times a day.

Do you have any suggestions on further troubleshooting? Or is it safe to say the OPV gasket is cooked and the whole OPV needs to be replaced?

well opening it up will be the way to know for sure but
the adjustment factor comes to play once you open it

no need to replace the complete OPV we (has most likely other vendors has well)
have the part for the rebuild
just note the type of OPV you have

Stefano,

So I used a pressure gauge and it looks like I'm getting 8.5-9.5/10 bars of pump pressure while pulling a shot. I think I'm good on that part so I won't need to adjust the OPV.

But the problem still persists when using the steam function. I notice that the steam is erratic: Strong flow of steam then erratic small puffs then strong again. Also, the steam is hotter and much more violent than usual.

Perhaps a thermostat?

What temperature does the PID display while steaming? If over around 310F at any time then you might have a temperature control problem.

Jim

Jim,

The highest temperature I've ever seen is 140c/285F. I have never seen it go above that ever since I installed the PID well over 1.5 years ago. Over the past few weeks and when this problem started, the PID is usually sitting at around 135c/275F with the steam function turn on and has not gone beyond that.

The bubbling through the over flow tube starts at around 115c/239F. It will continue to bubble until maybe after 5-10 seconds into the milk frothing process. Even then, it's too difficult to control as the steam pressure is just so violent now.

Edit: Come to think of it - my shots of espresso are hotter than usual. Uh oh.

Mike -

Based on those temperatures, I would not suspect the problem is related to thermostats or PID temperature control. Your temperatures are in line with normal operating temperatures.

My guess is you'll find Stefano's diagnosis of a problem with the OPV will be the correct one. Either you have some scale in the valve that is preventing a good seal, or the rubber is disintegrated. Not too difficult to fix, but you'll need your plumber pants

Jim

Jim & Stefano,

Thanks for the help. Much appreciated. I'll pick up the OPV locally. My understanding is the OPV is brass itself with 4 washers - http://www.espressotec.com/index.php/pa ... -5014.html

Not sure how scale would build up in there. I live in Vancouver, BC so the water here is pretty soft. And where is there rubber in the valve?

Is this the correct part? I hope it's not a royal pain in the *** to remove.

Edit: If this OPV solves the problem, Jim & Stefano, you saved me from buying a new Bezzera Magica E61.

Here is a pic of a Silvia OPV - a few years past the original. The original did not have the stainless steel shims/washers you see. Yours is SIMILAR except, of course, it has a threaded adjustment for the spring.



The part all the way on the left is the valve and, as you can see, the "rubber" valve face is sorta held in place by a small machine screw. The rubber is the part you need to replace. Replacing the "rubber" alone is normally easy but accidents do happen and therefore some shops tend to sell the entire valve (the part on the left). This should be understandable.

The copper crush washers (not shown in my pic) come into play only when one replaces the entire assembly because it needs to be oriented properly to meet with the hose from the pump.