Hi, all. My Lelit Elizabeth v3 is around 3 months old now, and has started to behave a little strangely with regard to pressure. If I put in the blind basket, then engage the pump (no preinfusion, and it's been an hour or so since last use), the pressure spikes up to around 11 bar, then drops quickly to around 10 and holds. If I then do this again very soon after the first time, the pressure will only go to maybe 9.5 bars and hold. Then on the third such run, and all subsequent runs in this sequence, it will just go to 9 and hold there. Something very similar happens with coffee in the portafilter, though the pressures there decline during the shot as expected. I have found on other message boards that a few others have also had this problem, but I haven't really found any solution. One person suggested adjusting the OPV, which I had already done long before this issue arose to set it to 9 from the factory default of 10. I did adjust it again just to see, and it did not seem to help. In fact, when I adjusted it I set it to around 8.5 bars (as the pressure it gives after several runs in a row with the blind basket at least), but the next day it was back to its previous level and behavior, as if the OPV adjustment had undone itself. Is this a case of a bad OPV? How difficult is it to change out the OPV entirely?

> @"Pygmalion"#p1227 Is this a case of a bad OPV? How difficult is it to change out the OPV entirely? it's not difficult, but it's very unlikely that the expansion valve (OPV) has gone bad. If it had you would probably be getting other sumptoms. For the OPV to cause the behaviour you're describing, it would have to be stiffer and open later for the first shot, then open a bit further when the pressure drops to 10 bar. Then as you do more shots…it is loosening up. That' not really normal behaviour for that type of valve. If it was sticky, then usually it would jam up on other shots, possibly randomly…it's also very hard for it to stick. As you can see, the only bit that moves is the pad, held by the spring against the port. There is not much to stick or jam. The only par that could is the relatively loose fitting metal bit with a pad. [URL=https://i.imgur.com/fX9CLwu.png][IMG]https://i.imgur.com/fX9CLwu.png[/IMG] From your description, the behaviour seems to follow a consistent pattern, which would indicate another cause. I'm just not sure what at the moment?

@"DavecUK"#p1229 Thanks for the detailed reply DavecUK (BTW, I'm using your advanced parameters for the Elizabeth; thanks!). I wonder what could cause an issue like this, then? Could it be a temperature thing? That is, the first shot might be hotter (if I haven't done a purge, which I often don't), then subsequent ones in somewhat rapid succession are a little cooler, etc. Would this make the pressure behave in this way? My understanding of the OPV is that it sets an upper limit on the pressure, and that it should never rise above this if the OPV is working correctly. Of course, that's only the pressure at the OPV itself, which is not directly what the pressure gauge is reading (pump pressure?). So, if the OPV is not the problem, then it could be the gauge I guess, or it could be that somehow the pressure in the system where the gauge is reading is higher than the OPV in some strange, consistent-ish way. Anyone else having similar behavior?

@"Pygmalion"#p1238 In a rotary pumped machine, odd things can happen because the water goes into a sealed system through a 1 way valve. The expansion valve in that sealed system is set to 12 to 14 bar. In your system it's the expansion valve as you correctly say controlling the pressure, so there is an upper limit….not really sure…am cogitatingt. I even though perhaps air in the capillary tube, but that wouldn't case the problem you're getting.

Morning all, I noticed this morning that I have the exact same thing happen! Preheated for about 40 mins, purged for 3-5 seconds out of the hot water tap, waited a minute or 2, puled a shot with a 10 second preinfusion at 2 bar, after the 10 seconds it shot up to 10-10.5 bar before dropping back to 8.5. Subsequent shots only reached 8.5 bar after PI (I did another 2, one for my wife, the other for 'science', aka my second double before 0700 what could go wrong). The strange thing is, the timings were all exaclty the same, 16g in, 33 out in 33 seconds. I'm wondering if it's more of an issue with the display then with the valve? I've possibly got some friends coming over tomorrow for a pre/post run brew so if I do more then 3 shots I'll pay close attention to the needle and report back...

I've thought about what might be happening by imagineering how I this could be created if one wanted to do so. and looking at the way the Elizabeths were made (factory photos of first production run…I can't see how it can happen, or be made to happen, unless i'm missing something. The repositioning of the expansion valve is still within the sealed brew area, and they changed it for a much better and reachable/adjustable valve. The V2 I had which I modified to a V3 still; has the old valve, as you can see from my review photos, and hydraulically is in essentially the same position (if not physically) https://coffeeequipmentreviews.wordpress.com/2020/05/08/lelit-elizabeth/ So here is the image, just to orient people 1. Expansion valve controlling brew pressure max 2. Manometer take-off for pressure gauge 3. Autofill solenoid for steam boiler, opens to fill steam boiler 4. Exit port from ring group to vent solenoid 5. Vent solenoid, opens at end of shot. As you can see 1, 2 and 4 , all form part of the sealed brew circuit. The expansion valve is directly connected to the boiler, whatever pressure is experienced by the coffee, the same pressure is seen by 1, 2 and 4. The other numbered components take no part in this. The component under the autofill solenoid (3) is what does the steam preinfusion and incidently takes part in the clever way the machine does hot water. This component can't have any impact as it still only feeds into the same sealed brew circuit controlled by the expansion valve. This means any thermal expansion of water would be controlled ultimately by the expansion valve. My only possible conclusion is perhaps a shock wave caused by any slight airspace and water hammer due to closing of valves? **Perhaps someone could try switching of bloom phase and steam preinfusion, just have a straight shot…then see if it happens** [upl-image-preview url=//i.imgur.com/B9miMjc.jpeg]

Do you mean turn off the steam boiler or just not have any preinfusion? If so I got it just now with just a stright shot, no 10 second bloom, just 8.5 bars. It still spiked up to about 10 bars and the second shot rose to 8.5 and stopped.

> @"Del_UK"#p1323 Do you mean turn off the steam boiler or just not have any preinfusion? If so I got it just now with just a stright shot, no 10 second bloom, just 8.5 bars. It still spiked up to about 10 bars and the second shot rose to 8.5 and stopped. Everything off, probably even steam boiler (even though it shouldn't matter)…but certainly both preinfusion functions (one is referred to as bloom phase). Effectively turning it into a dumb machine. If it still does it, more evidence for a water hammer effect due to air…well that's the theory. ***P.S. If you turn off steam boiler…wait until it's below 100C***

Thanks for all the continued feedback and interesting information, everyone. Also glad (sort of) to hear I'm not alone. DavecUK, this happens even when using no preinfusion of any kind, and also with steam boiler off and cool.

I will keep an eye on mine. I never noticed this. But then again, I only have one coffee in the morning, and one in the afternoon. If there’s any testing I could do, please just let me know. 👍

@"Pygmalion"#p1333 If that is the case, I can only assume it must be a transient water hammer effect type of thing due to air? I would expect it to have no impact on the shot. Any chance of video of it doing it?

Lelit Elizabeth pressure spiking/inconsistent

MediumRoastSteam

Ando all you need is a torx 20 for the screws of the top lid of the machine.

Shower screen uses an hex 3.

JahLaza

MediumRoastSteam cheers, I never did get around to detailing exactly which were which but careful not to wreck the threads😌

MediumRoastSteam

Pygmalion

JahLaza

Good work! If you have removed any hoses from any of the fittings, do make sure you secure them with a cable tie. I had previously done so before at the X connector and the hoses would just disconnect quickly after starting up.

Pygmalion

Ok, everyone, as promised, here are my results.
(edit: couldn’t quite figure out posting the images directly, so here is a link to the online album)
https://photos.app.goo.gl/gbTxcjyZBs81vKEK8

When I unscrewed the cap, I could hear the spring inside making spring-y noises. Not so important but I will contrast this later.

As the images show, the plunger looks to have quite a bit of some kind of corrosion on it. Covered in white stuff and quite discolored in general. All except for one part that looks to me like copper, which I believe is where the spring was resting. I can’t say that the material looks nickel coated, but it is a little hard to say given the state it is in. Personally it looks more like copper (given this exposed spot) coated in brass, if that makes sense, but I’ll let you judge from the pics.

The spring is also coated with a lot of white stuff, as you can see in one of the photos. Not sure what the spring is made of. I guess I would have hoped stainless steel, but since it was coated with white crud I’m guessing not.

Anyway, I cleaned them off the best I could, lubed the plunger metal (and top o-ring) with Molykote 111, then put it all back together. I screwed in to right where it was previously (had made a mark with permanent marker on a thread just outside of the screw-in area); no spring-y noises as I rescrewed.

Upon heating and engaging the pump into a blind basket for the first time, the pressure did NOT spike, but only went to around 7.5 bars! But, upon a second run, it went to basically the same number, so that was promising. I had to screw the top of the OPV in significantly more than it was previously to get pressures up to more reasonable numbers, and now it seems to be at around 9.5 bars with the blind basket and current screw-in point. So far, it seems much more consistent shot-to-shot; I’ll report back on this specific point tomorrow morning after my first shots of the day.

Fingers crossed that this has at least temporarily fixed the issue. I would love to not have to do this again, though, as re-assembling the OPV was a little tricky, since you have to keep some pressure on the end while trying to engage the threads without cross-threading. I guess if it’s once every few years, I can live with that, if there is no more permanent solution available.

JahLaza

Pygmalion sounds like you’ve had the same experience/result as me, great. I’m on the hunt for molykote now, it’s scarce stuff!

@MediumRoastSteam thanks for that, I remember you had said that before (somewhere!) I will do that in the morning

DavecUK

That’s cool, looks like my guess as to the cause might well be right. We just need 1 more person to “fix” their pressure problems and then I believe we can call it “confirmed”

@ Giphy -

Pygmalion

Thanks for the tip about the zip-tie, @MediumRoastSteam. My one concern with this is that, if I need to remove the tube again, it might be tricky to cut the zip-tie so that I can do so without damaging the tube. Do you have any recommendation with regard to this?

@DavecUK, will you be informing us as to the details of your guess at some point, if it is confirmed? I’d love to know, being the geek I am. In any event, thanks again for your help with this.

MediumRoastSteam

Pygmalion cut the zip-tie so that I can do so without damaging the tube.

You can buy a bag with 50 ties for about £1.50 or something. If you need to undo it again in the future, you carefully cut the zip tie with a wire cutter or cutting pliers. There’s no need to damage the tube in the process what so ever.

JahLaza

Just to follow up- Shot was exactly as should be this morning as after fix yesterday - up to 9.75/10 bar and settled around 9.5 bar for the shot duration

DavecUK

Having seen the second fixes set of photos, I can clearly see the valve pad is brass. Now the bad news ish….I am also of the mind that the pad should be lubricated as well as the sides of the pad holder and possibly a thin smear in the area of the bore where it moves.. We are talking a thin smear on the pad. In all probability the cleaning alone cures “pad stick”…but lubricateion is going to reduce the possibility of return, if “pad stick” is a thing?

This will help prevent any build up of deposits and also help ensure any possibility of “pad stick”, doesn’t allow the pad to lift unevenly then try and jam…this is a guess, but on reflection I would do this. I know you guys still need to get some Molykote III, so when you do, you can do the job with that…it has hugely better washout resistance.

Then the best water you can with the lowest amount of dry residue and something that won’t leave deposits, or varnishes on the valve. The valve is actually of good quality, so it’s odd that this can happen…but clearly with good water it doesn’t seem to be an issue @MediumRoastSteam.

My current view is the fix will last a very long time …years and the more often the valve opens and closes as it does in daily use, the more it’s going to move freely anyway..

Pygmalion

Thanks for the updated advice, @DavecUK. I will indeed disassemble again and lubricate more fully, as you suggest. When you say “a thin smear in the area of the bore where it moves”, are you talking about the inside of the valve body? Just want to make sure.

Also, I think that in order to lubricate the inside of the body, I might need to completely remove the valve. Should I expect the threads to be stuck on with some kind of loctite that I might need to contend with, or will standard hand tools and procedures suffice to remove the valve? Also, upon re-installing, should I use any such product, teflon tape, etc?

Finally, I just want to clarify that I think I am already using very high quality water in the machine, which is simply distilled water with trace minerals added back in according to the 70/30 water recipe. Is it your opinion that this recipe is not good? If the recipe is alright, then this issue can still crop up even if the water is good.

DavecUK

Pygmalion very, very, thin smear of Molykote, hardly any as you don’t want lumps of grease entering the pump. The idea is to get it clean, non stiky and scale free. By the bore I means dry it throroughtly inside and with a finger or a cotton bud, just a thin thin smear around the bottom area where the pad thing moves…it only moves 5 mm. Do not remove it from the machine.

When using Molykote, everything must be bone dry….don’t do the pring or high up in the bore, just the o ring at the top where the plunger assembly moves in and out, as that o ring seals from leaks.

P.S. really really thin thin coat (did I already mention this)

Ando

Is this the bit I’m interested in? Detach the plastic tube then unscrew? Just wanting to double check before I get started later on.

And that bit I’m screwing is the bit that adjusts the pressure?

Thanks in advance

DavecUK

Ando Yup that’s correct….don’t get it wrong, or you might be screwed. 😉

Ando

Think I’m sorted - all seemed fine with blind basket but had to pause as the plastic tube flew off the OPV as @MediumRoastSteam warned.

So cable ties tomorrow and should be fine.

I have photos if required but doubt it will add anything - similar to others there was white stuff on spring and small part with green pad on it. That bit had clear corrosion on it with pinky bits exposed once white stuff off.

Is water def the culprit here?

Thanks very much for all the help - really appreciate it! I should add - having extremely large hands did not make this easy! Haha!

MediumRoastSteam

Ando plastic tube flew off the OPV

Silicone sir, silicone! 😂😂😂😂😂👍👍👍👍👍

DavecUK

Ando The very thin layer of Molykote will significantly reduce future deposits.

JahLaza

@DavecUK my molykote should arrive in about 2 weeks I’ll redo then. Just while it’s hot here, can you please confirm where I should apply the molykote? O- ring, yes, sides of pad holder (I’m guessing the metal circumference of the brass pad holder which glides over and back inside the housing)- yes, the area of the valve housing where the pad/piston head will move-yes fine. You said above to apply it to the pad also, what did you mean? Apologies if it’s obvious but I just wanted to be crystal clear as don’t want to be doing it too often. I’ve noted it’s a THIN LAYER!

DavecUK

JahLaza The sealing pad so deposits won’t form and it can’t stick..

Very thin layer…on totally dry components.

Pygmalion

Hi, all. I wanted to give a quick update on this for those interested. I performed the extended lubrication, including pad (very thin layer) as advised, with Molykote. All seemed well right at first, but the behavior has now returned, with initial pressure spikes even higher than before.

Anyway, I’m in contact with my retailer, and they have assured me they’ll get it sorted.

I hope the fix continues to work for others, and I’ll keep monitoring this thread to see if anything more develops.

Ando

Pygmalion Not good news. Where did you buy it from? Sounds like a promising response from them.

What water do you use with machine? Someone mentioned Osmio, was that yourself?

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