Elektra Microcasa a Leva with scary boiler pressure issue

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nile13
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#1: Post by nile13 »

First, let me say that I'm a complete newbie when it comes to lever machines. I've used a Silvia for the last 2 years and have somewhat decent shot but decided to try a lever. Bought a used 1983 Elektra and tried for the first time today. The seller assured me that seals were changed recently by a professional shop in NYC and that machine has worked very well for them.

Issues:

When machine started warming up water was dripping significantly from the bottom of the grouphead and from the seal between grouphead and boiler. The dripping subsided somewhat, but it kept dripping.

After 3-4 minutes the pressure started rising from 0 and continued to go up until it pegged out beyond 3 bars. At this point I got scared and turned the machine off.

Pressure dropped in about a minute. I turned the machine back on and bled the rest of the pressure slowly through steam wand until it showed 0.

Turned steam wand off. The pressure rose within a couple of minutes or less to 2+ Bar and kept rising.

At this point I've turned the machine off in sheer terror. I have a nasty feeling that pstat might be stuck and this thing can simply blow up. What am I missing here? I'm beginning to think that as much as I like this machine it might not be for me. Help the newbie, please!

The pressurestat under the machine looks like this:


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HB
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#2: Post by HB »

For those following this thread, Mike cross-posted the same question on CoffeeGeek here.

Back to the OP, it sounds like the pressurestat is stuck. Given its age, it would not be surprising if the pressurestat contacts have welded themselves together. Stefano's EspressCare sells replacements: MATER pressurestat (note the model has changed over the years but they're compatible).

It's also possible that the tube leading the pressurestat is clogged with scale, preventing it from getting an accurate reading. Again, given its age, it's likely overdue for a descaling. You may find these threads helpful: How to adjust Elektra Microcasa a Leva pressurestat? and Descaling an Elektra Microcasa a Leva.
Dan Kehn

nile13 (original poster)
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#3: Post by nile13 (original poster) »

Dan, thank you very much!

I've crossposted because I've read that first thread you've suggested (p-stat adjustment) here and thought that I could get more help with this particular issue on HB. Hope it's not a problem as I don't want to break the decorum with my very first post.

The thread was extremely helpful to me and I'm thinking i'll be taking the p-stat apart to see what's going on. Unfortunately i don't have any tools with me in Florida (home is Boston) and I'm here for the next two months so... replacing a p-stat with a newer one might be the right solution for me. Stefano is out of town, it seems, for the next week and a half so i wanted to line up the list of parts I need to get from him.

It was also suggested that my heater element might be cracked. Is there a quick way to check the p-stat operation? Perhaps disconnect it and see if pressure doesn't rise at all? Any ideas on simple troubleshooting steps here would be great!

Again, thanks in advance, any and all help is greatly appreciated.

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uscfroadie
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#4: Post by uscfroadie »

Mike,

Orphanespresso.com has NUMEROUS troubleshooting tips/guides on their site. Though they may not have your particular model in their tutorials, the same principles will most likely apply. Add to that their stocking of many parts for just about ever lever currently being used, and they are a place you have to visit. When it comes to levers, no one is better than Doug and Barb at OE.
Merle

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HB
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#5: Post by HB »

nile13 wrote:It was also suggested that my heater element might be cracked.
That makes no sense. A pressurestat is simply an on/off switch controlled by a diaphragm. Pressure in the steam boiler rises until it pushes hard enough on the pressurestat's diaphragm to force the switch open (see this explanation for more details). If there were an issue with the heating element, the boiler would be stone cold.

While we're covering espresso 101 topics, the reason your boiler didn't explode was the pressure safety release valve. It's basically a spring-loaded valve that cracks open if the steam boiler's pressure exceeds its setpoint. It's good that your safety release valve works, but you really shouldn't use the machine until the pressurestat issue is resolved.

See Elektra Espresso Machine Explodes in Sainsbury's for more details.
Dan Kehn

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cannonfodder
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#6: Post by cannonfodder »

Dan, it sounds like his safety valve is stuck which is what scares me. Those open at about 1.7 bar. If you really had 3 bar in the boiler it should have been venting huge amounts of steam everywhere. What you have is bomb waiting to go boom. I would unplug it for the sake of safety.

You have several problems. Your grouphead to boiler is leaking. Someone probably removed it for cleaning and either did not put a new gasket back in or did not tighten up the bolts. Dripping from the grouphead is bad seals in the piston, you pressurestat is stuck closed so it will heat until it explodes and your boiler safety valve to prevent such an explosion is not working. The pressure safety valve is usually in the boiler cap. If you take the boiler cap off and look at the underside there is probably a pencil sized disk recessed in it. That is attached to a spring and gasket. The pressure gets too high, the piston is pushed up against the weight of the spring opening the gasket and venting the excess pressure. They do stick now and then from age. You need some work.
Dave Stephens

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HB
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#7: Post by HB »

Thanks for the correction Dave, you're right. The safety release valve isn't working. Given this and the OP's opening comment...
nile13 wrote:First, let me say that I'm a complete newbie when it comes to lever machines.
I think it prudent to let a qualified repair technician take over.
Dan Kehn

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rpavlis
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#8: Post by rpavlis »

When I acquired a 1999 brass La Pavoni Europiccola it was packed with Calcium carbonate from the former owner's use of hard water. Espresso machine manufacturers will not honour guarantees when people use hard water in them. You should look inside the boiler and check that it is not a mass of calcium carbonate. The tube leading to the pressurestat on mine was clogged. Many suggest the use of citric acid to remove calcium carbonate deposits. There is a serious problem with using it to try to remove deposits from passageways such as the tubes leading to pressurestats and sight glasses. Citric acid has three acidic protons. When all three are removed you form the triply charged citrate ion. Calcium citrate is insoluble. When the citric acid has to diffuse into tight spaces it does so slowly so that it can form citrate and replace the solid calcium carbonate with solid calcium citrate. A better acid is white vinegar. It is about 1M in acetic acid. The disadvantage is that if you fail to get it all washed out you can get espresso that tastes like a salad! However it will be sour if you do not get the citric acid out also.

The filling cap on the MCAL is small. Someone made the suggestion that one could use the special LED lamps used to look down fire arm bores to light up the interior of the boiler. (That seems to me to be an awful thing to do!) However, you can buy these at gun shops inexpensively. I followed the suggestion, it works great on the MCAL.

I only use distilled water in both the MCAL and Europiccola. Most people seem to be unaware that Ca, Mg, K, and Na that some think important in espresso is always present in the coffee. I personally do not want to have the tastes that are in most tap water. There are absolutely no calcium carbonate deposits in my machines, and I never need to treat them with anything.

The top of the MCAL piston is not exposed to steam, there is a small hole on the back of the group to let in air. If there be bad seals, water will come out of this small hole.

As mentioned by others, both a bad pressurestat and bad safety relief valve on a machine create a bomb!

nile13 (original poster)
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#9: Post by nile13 (original poster) »

As a (former) engineer I understand pretty well the concept of rising pressure with no venting. That's why I vented through the steam wand and after realizing the pressure was going up again shut the machine down.

I will try to address one thing at a time. First is fixing the p-stat. If I understand correctly, it's possible to replace the diaphragm on the one I have. As an option I can get a new p-stat and see what it does. I also think I need to de-scale the machine, but is it safe to attempt with a dead p-stat?

Secondly, the pressure relief valve. I'll look at the cap. Should the pressure valve be movable by hand if pushed hard? Should the fill cap be soaked in something to see if it starts working? I take it that I should see steam coming out of top of the machine at anything above 1.7 bar?

The gasket between the boiler and grouphead is there, I can see it. It's possible that it's old and brittle from not being used for a while. Replacing it should be fairly easy.

The other gasket that causes a leak through the grouphead is trickier. How hard is it to replace? I've sent an email to orphan espresso but hot no response in a week. They are busy and I can respect that, I will try again.

Having said that, are there any repair shop around Miami that could be recommended to look at this Elektra?

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HB
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#10: Post by HB »

nile13 wrote:I also think I need to de-scale the machine, but is it safe to attempt with a dead p-stat?
I don't see why not, there's no need to plug it in since you can mix descaler (hot water + citric acid) and pour it in. If you need to heat the boiler, turning it on for a few minutes should suffice.
Should the pressure valve be movable by hand if pushed hard? Should the fill cap be soaked in something to see if it starts working? I take it that I should see steam coming out of top of the machine at anything above 1.7 bar?
Never tried. Could work. Yes.
The other gasket that causes a leak through the grouphead is trickier. How hard is it to replace?
It's a surface mount O-ring, so replacement is straightforward if you're modestly handy. Given the age of this machine, I'd replace all the gaskets. See Piston gasket replacement on Elektra Microcasa a Leva and Replacing grouphead gasket on the Elektra Microcasa a Leva.
Dan Kehn

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