Group Boiler Temp Probe Alarm

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coffeeowl

Group Boiler Temp Probe Alarm

Post by coffeeowl »

Hi!

I got the 20/21 lights alarm today, non-blinking.
Before I consulted the manual I switched the machine off and back on and the alarm disappeared. Then I went out, when I got back home the alarm was again on. I again switched it off and on and the alarm is gone, but the group boiler is not hot and if set to any temp the diods show like it was up to temp.

Is there any chance it will be back to normal by itself? It's possible I was drinking to little coffee last days (while the machine is on).
Or do I need a repair?
Endo

Re: Group Boiler Temp Probe Alarm

Post by Endo »

You need to repair it. The probe is covered in a copper tube which likely cracked and let in water due to stress corrosion cracking at a manufacturing weak spot near the base (or possibly the tip). At least that would be my guess.
Group Temp Sensor
Group Temp Sensor
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chas
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Re: Group Boiler Temp Probe Alarm

Post by chas »

What happens if you unplug the machine and then plug it back in, rather than just turning it Off and On again? If the manual is correct this is supposed to be a blocking alarm which is only supposed to be clearable by unplugging.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
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coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Yes, that is precisely right: I unplugged it and plugged it back, both times.
So unfortunately you're right, I let the machine cool off completely and still the brew boiler does think it's up to temp.
There was a short moment the temp diod blinked and then shortly afterwards again for a moment, but otherwise it keeps showing it's up to (any) temp.
The boiler gets warm though, I wonder how. (I still use the steam boiler). The alarm doesn't come back.

I will have to call service, I think. The one time I wanted to open the machine,I was unable to unscrew the screw under the cup warmer tray. So I gave up.
Must say, I am probably the only owner who didn't open the machine for so many years. :smile:
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Ok, so I have the alarm again: today afternoon when I turned the machine on again I noticed the brew boiler is getting warmer and warmer. I drew some water from it but the led indicating reheating didn't blink. Then I noticed the alarm was back on after a few minutes. And the boiler was hot.
Now I understand better what's going on.
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

So after I let it cool off a bit and plugged back on again, after a short while I got again the alarm, and then also the blinking one.
So now the machine is off till I repair it.
Anybody has any idea should I get to it myself or call the service? There is service in Poland fortunately.
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chas
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Re: Group Boiler Temp Probe Alarm

Post by chas »

If you have a Volt-Ohmmeter you can do a couple of quick measurements on the temperature probe that will give you a good idea if it is the culprit. Unplug the S1 and let it completely cool first.

A couple of inches along the probe wire from the back of the boiler are orange sleeves around each wire which are held in place by nylon cable ties. Cut those cable ties and slide the orange sleeves along the wire until you expose the connectors on each wire. Disconnect both wires.

Ohm across the wires going to the probe and be sure the probe is neither open nor shorted. Then place one ohmmeter probe on one of the temp probe wires and touch the other ohmmeter probe to the boiler casing. This should be open. Do the same thing to the other temp probe wire. If you get a short or any ohm reading other than an open circuit (infinite resistance), you have leakage between the probe and the chassis ground.

If any of these things prove to be the case, you should replace both the probe itself and the tube that the probe is inserted into. The tube actually screws into the boiler and then the probe is just pushed to the bottom of the tube and then sealed in place with a small dollop of silicon sealer at the top of the tube.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
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coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Chas,
thank you so much for the thoughtful reply!
If you had also advice on how to loosen the under-cup-warmer screw, I'd be even more thankful.

However, I have update.
When I plugged the machine today morning, there was no alarm and the brew boiler thought itself to be up to temp. I wanted to use the hot water tap so I left the machine on. The brew boiler was warming slowly. I figured, I'll switch my machine off to not let it overheat and not set the alarm off. So I did. Then at noon, after another switch-on I noticed the brew boiler diod was blinking since the beginning. I was surprised, though the diod occasionally for a short moment was blinking (I had it set to 91C). But then the boiler was rather not hot and the water was probably 60C warm.

I also tried a backflush and it didn't work (no pressure, which is no surprise the water temp was off).

But then I drew some water from the group. The boiler temp diod was steady.

But then after another switch-on, the diod was again blinking since the beginning and when it stopped, the boiler was hot and the water from the group was hot too. It was up to temp.
Then I started drawing water from the group to see how it behaves and it did somewhat normal. Also it did backflush.
Then the alarm (steady mode) poped. I unplugged and plugged back, raised brew boiler temp and drew a lot of water, it behaves normally... and it is the state of it now. It cycles normally and is up to temp.

I think it must be my water. RO mineralised, after sitting in the boiler for too long, fooled the sensor?
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chas
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Re: Group Boiler Temp Probe Alarm

Post by chas »

coffeeowl wrote:Chas,
thank you so much for the thoughtful reply!
If you had also advice on how to loosen the under-cup-warmer screw, I'd be even more thankful.
I think what you will need to do it find a hook or something hook-like - bent piece of wire or coat hanger perhaps - and use that to pull up on the cup warmer tray while you undo the screw.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Thanks!

So I have the alarm (steady) back on. :-(
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chas
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Re: Group Boiler Temp Probe Alarm

Post by chas »

If you need to end up ordering a temp probe and probe tube and if you haven't opened the group boiler in 6 years, I would recommend also buying a new boiler gasket, removing the back and descaling while you are going through this effort. I think there are a couple of how-to threads you can find here from folks that have done that in the past.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Thanks again! It's not six years, but four and a half. :smile:

However, an update:
the steady alarm was on display all time I tried to plug my machine back yesterday, also after it cooled completely, but then in the evening it started disappearing for a moment after plugging back. Today morning was the same thing, then I got the blinking for a while, then it started like normally warming for a minute and again the steady alarm.
I concluded it's impossible for the Vivaldi to be damaged and behaving like it was.
Also, giving it all a little thought, I realized that the brew boiler probably wasn't overheating but just the alarm was coming. Just like today morning on the cool boiler.
I also understood that there's no time-out after the alarm comes, nor cooling fixes it.

So thinking about I concluded that maybe there is like a static dust inside (I haven't vacuumed my Vivaldi all that time :oops: ) and so I plugged in my vacuum cleaner and blew into under the cup warmer (well... have to get to that screw anyway, but I wanted first to know what's up). Guess what? After the cleaning my S1 is back up and going!

So I definitely need to open her and look inside, but thank goodness I don't need repair!!
Endo

Re: Group Boiler Temp Probe Alarm

Post by Endo »

Don't kid yourself. Something is not right if you are getting alarms, even if they are intermittent. They are warning signs tha you should listen to.

Doing the resistance check is simple. Opening the boiler is necessary every few years if you want to prevent more serious damage later on. It's easy to do in a workhop with a few simple tools. If you are not handy, find a espresso tech who will do it.
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Yes sure, you're right. I will.
And yes, I think I rather will start myself, for the service in quite far away and I'd rather see it all and learn.
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Ok, so I got the alarms back (they'er changing though).
Now please somebody seriously tell me how do I unscrew the under-cup-warmer screw? t has soft head and now it is no longer catching any screwdriver.
Endo

Re: Group Boiler Temp Probe Alarm

Post by Endo »

6 years and you never removed the cup warmer tray ?? :roll: OK then. The cup warmer cover has only one single fine thread philips head screw, centered right in the front. It may be seized if you never opened it in 6 years. If it doesn't turn, try going to the harware store and get a bit of pentrating fluid (Release-All or whatever). Put a couple of drops on the screw and try again the next morning with a new, unworn screwdriver and a good downward pressure.
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Actually 4 and a half.

Ok, I used WDT-40 on that damn screw and nothing happens yet. Except that I bent the cup warmer tray up to have access from the bottom to the screw. So I will remove it and then bend the tray back.

But, I must say: I remeber there were posts on removing the covers from the machine but I can't find them by search. Also there were posts on removing and reattaching the side panels. I remeber an instruction step-by-step on what screws to unscrew, but I can't find it all. If anybody remembers them please point me to that or put info on how to do here.

I removed the screws holding the right side panel and I don't know how to remove the panel?
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

SHE GAVE IN!!! :grin:
Only after another amount of WD-40. Yeah!

So I found another screws that were holding the side panels in place. Now my machine is all stripped off!

It's late here so another things I leave for tomorrow and so on.
Though was curious about the boiler temp probe and wanted to look at it but have hard time locating where it is. :shock:

p.s.
the piece that bent in order to bend the cup warmer tray up-away, is already back to normal. :smile:
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

I didn't do any measurements yet, because:
1. The alarms are gone, only the boiler being cold thinks himself up to temp;
2. Now also Vivaldi forgot the programmed volumes on both single cup and double cup buttons. Delivers just a tiny bit of water through the group and cuts off.

Any idea what is going on? I think this should be logically deductible now?

P.S.
Ok. Yes I zeroed it myself accidentally of course. It works fine. So the point 2 is non-existent.

I found a strange looking loose black double wire at the back of the brew boiler. It comes out and then there is resistance, so it seems to be attached inside the boiler, but there is normally a hole in the back of the boiler through which it comes out. There is also some like build up on the wire, or maybe it is some kind of sealing? Anyhow, water doesn't flow there.
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

So the wires I talked about, they're the wires going from the temperature probe. How do I know? Well, because moving the wires in and out sounded like something was going through a hole, in and out. So while I tried to move the wires a little, then they loosened and all the temperature probe went out from the boiler from behind. The state of the machine is with no change - displays brew boiler is up to temp.

So there's something screwed onto the boiler from behind and from that the wires of the heating element and the probe go out, right? It looks like a collar.

Also, from what Endo wrote, the probe goes into a metal tube that sits in the boiler. So that's why I don't have a hole in the brew boiler?

So what do I need to do from here?
Thanks,
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

I don't want to bore you all here or have a monologue :smile:

The probe, I noticed, is a bit wet when I remove it from the boiler. So Endo was right, there's a leakage.

I also talked to a technician from the service and he confirmed me and suggested that I could do the repair myself.

I'm enthusiastic about it,however I'd like to confirm there's nothing more. For I have no alarm, just the cold boiler reading itself up to temp, and even if I remove the probe there's no change. Anybody has any insight on that?
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chas
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Re: Group Boiler Temp Probe Alarm

Post by chas »

If there is some leakage inside the group boiler's probe tube such that the probe housing is wet, that won't necessarily cause a problem. The problem comes if the moisture gets inside the probe itself. If that happens, the problem will persist whether the probe is inside or outside the tube. There is a pretty easy way to narrow down if this is the problem.

A couple of inches along the wires from the probe, each wire is covered by a fibrous orange tube. These two tubes are then held in place by a nylon cable tie. If you cut this tie, you should be able to slide the orange tubes along the wire to expose the connectors on each wire. By pulling these two connectors apart you can disconnect the probe from the wire that goes to the control board. Now, plug the S1 back in and turn it on. This time you should get the 20-21 alarm again due the the controller boiler detecting that the probe is in an open circuit condition.

Someone else is having the exact same problem which is being discussed in another thread. Chris Coffee recommended to them to try to connect the wires going to the controller board from the group temperature probe to the steam boiler temperature probe. This will make the controller board think that the temp probe in the steam boiler is actually in the group boiler. The group boiler should them start to heat up normally. However, since the probe is actually in the steam boiler, and the steam boiler does not start to heat until the group boiler is up to temperature, the water temperature will not exceed 60C within 5 minutes so at the 5 minute mark you will again get the 20-21 alarm. However, if the group boiler is heating normally during this 5 minute period, that will definitely indicate that the group temp sensor is bad.

Here is the other thread if you haven't been following it: 20-21 Alarm Issue
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Thanks!

I did disconnect the wires and what I get is the Vivaldi in normal mode, that is the diod indicating the brew boiler temp blinking.

I saw that thread where Chris suggested swapping the cables. Thanks for the other link. (edit: Oh I saw it earlier too)
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

So I ohmed the thing.
Reading from the probe to the boiler case is open circuit, but also reading from the probe to the wires is open circuit.

By the way, I let the machine heat (only steam boiler heated) and - guess what - I'm getting the 'steam boiler doesn't refill' issue (I was talking about it here). This is clearly related to the length of time the water is sitting in the boiler.
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Re: Group Boiler Temp Probe Alarm

Post by chas »

Have you ever removed the steam boiler water level sensor? If it is too encrusted with minerals it might not properly detect when it is no longer submerged. It is pretty easy to slightly loosen the nut and then pull the sensor up and out for inspection.

The way this sensor works is that, when submerged, there is a resistance through the water from the sensor to the grounded boiler container. When detected by the controller board, this resistance shuts off the pump and de-energizes the solenoid. If the water level sensor is out of the water, or insulated from contact with the water by too much mineral build-up, or you have distilled water in the boiler, it will not work correctly.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

No Chas, I haven't, I am not sure which one it is.

But if the boiler empties too much, then cooling it off completely and plugging the machine back heals that (just like it happened to another person in the beforementioned thread).

How about the open circuit on the probe to the wires? What does it mean?

Still the machine sometimes recognizes brew boiler is cold and then tries to heat, but then usually it thinks too early it's up to temp.

Isn't the reason for both issues connected or somewhat the same?
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chas
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Re: Group Boiler Temp Probe Alarm

Post by chas »

Loosen the smaller top brass nut pointed to by the red arrow and also disconnect the wire. The probe should come right out when you pull unless it has such a large build up of minerals that it won't fit through the hole. In that case you may have to loosen the nut all the way and remove the whole thing. You might also check the condition of the wire where it connects to the crimp connector at the water level probe to ensure that the heat and humidity have not corroded it. That's another thing that could cause the problem.
Steam Boiler Water Level Sensor
Steam Boiler Water Level Sensor
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Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
coffeeowl

Re: Group Boiler Temp Probe Alarm

Post by coffeeowl »

Hi Chas. Thanks for the explanation. I had a bit busy time and couldn't respond earlier.

There's no build up on the probe, I use very soft water it seems. The cable on the probe seems intact.
After I unplugged and cooled off, Vivaldi refilled once and then, well - didn't. I drained the boiler and it's empty, still does not refill.
Probably, if I was using the machine, the issue would disappear like it did the other time.

By the way, the reason or circumstance of this problem is water in the steam boiler sitting for too long - what does that mean? The water gets distilled in the boiler (due to being soft) and then something happens? If I put distilled water in the boiler what would happen? And how to undo that?

I have no more the alarm, I did try to let the machine heat the brew boiler, it does detect it up to temp too quickly. I understand the issue with the probe is clear - damaged probe if the Ohm reading from cables to the probe is open circuit?

Opposite to what you said is that when the probe is disconnected, my machine doesn't display alarm.
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