Help please: cloudy water, then blocking alarm on mini V2

[bernie]

I heard a 'ting' sound, a bit like dropping a coin into a glass, and then cloudy water started coming out of the brew boiler of my Mini Vivaldi II. The water soon cleared, but now I get the blocking 20/21 red light alarm. If I unplug the machine and turn it back on to clear the alarm, the alarm clears, but the brew water never appears to get to temperature. I have the bolier set at 93c, but it never reaches that temperature acccording to the panel. If I run the brew boiler the water is warm, but not properly hot.

I have replaced the brew boiler triac and the temperature probe in the brew boiler and it has made no difference, the blocking alarm remains.

Any ideas or help would be appreciated. My Mini is three years old and so out of guarantee.

[chas]

The noise sounds like something popped loose inside the group boiler and temporarily stirred up the mineral layer. It sounds like you are in for opening up the back of the group boiler and at least descaling it. You may also need a new group heater element.

If you have a Volt Ohmmeter there are a few readings you should take first. 1) With the S1 power on and the boiler heating, use the VOM in AC volts mode to ensure that you have 220V (assuming you are in the UK!) across the element leads. 2) With the power disconnected and the group boiler leads pulled off, ohm between the heater elements power leads. This should be approx 40 ohms. Then ohm individually between each lead and the group boiler housing to ensure that both these readings are infinity; i.e. no leakage to ground on either side of the power leads.

If the voltage is off, then there is still something not right with the triac circuit. If any of the ohm readings are off, you probably need to replace the heater element. Otherwise, it might just need a descaling. If you open the back of the boiler, you will need to have a replacement gasket on hand in advance. If your finances allow and you want to minimize down time, you might also order a new boiler element just in case.

[bernie]

Thanks for the reply.

For what it's worth the Mini has only ever had Volvic water in it, never tap water, so I am not expecting a scale issue. I'll get out my meter and perform the tests you suggest.

Many thanks.

[chas]

Maybe Volvic sources a different product in the US than you have available. All I see from Volvic in the US is still mineral water which appears to be loaded with minerals.

[coffeejn]

I would not assume that there is no scaling happening... All bottled water have minerals and it does build up either way. So descaling might be worth a shot. 1 teaspoon of citric acid (it's cheap, can be found at a wine store) in 1L is all it takes (mine likes to drink <2L at a time just, a heads up if you do the group and boiler). You just drain all the water possible and feed the mixture, then heat it up then turn it off. Let sit for ~20 minutes then drain. For the group head, remove the screen to have a direct flush when you empty it. Just keep it away from chrome...... Here are the general instructions I followed:

http://www.frcndigital.com/coffee/HowToDescale.html

I though the same way as you on bottled water, but I had build up either way. So regular flush helps quite a bit.... The water that came out of my group head was blue after 20 minutes of soak and I never descaled the machine in ~7 years. Always used bottled water too.... So, ok, descaling every 7 years is a bit lazy for me, but I plan to do it every 6 months or yearly from now on.

Just my two cents.

[bernie]

Thanks for your replies.

I think it is the Group element and I now have a replacement element. I am going to have a go at replacing it this weekend and I'll post how I get on.

For those who have opened the Group boiler, what do you do to stop water going everywhere? Am I best placing the machine on its side when opening up the boiler?

[Endo]

For those who have opened the Group boiler, what do you do to stop water going everywhere? Am I best placing the machine on its side when opening up the boiler?

Lean it all the way forward when you remove the brass nut and the water won't spill.

[bernie]

I tried opening up the group boiler by undoing the brass nut holding on the element. No matter what tools I use, and I have a 'c' spanner, it doesn't want to turn at all. Obviously there is little space in the machine and I don't want to break anything, so how much force should I be using? Is it normal to need lots of force to remove?

[Endo]

It takes a bit of force to remove. Also, there can be some rust around the threads if has never been removed for some time.

I loosened it by tapping on one the lugs of the castled nut with a piece of wood and hammer (see the picture in my blog). I've also seen people wrap the nut with a rag and use a pipe wrench. You may also use a bit of heat on the nut.

Although, I take no responsbility for what may happen if you try any of these methods. The castled nut is a brittle cast material and the lugs can break off rather easily. Your spanner is definitely the safest method since it loads 2 logs rather than only 1. Still, everything can be replaced if needed.

[bernie]

First the really good news, I have replaced the element and the Mini is working again

I used your method Endo, of a hammer and piece of wood to remove the 'castle nut'. The element had to be prised off, fortunately as it started to come away, water came out in a relatively controlled way straight into the mug I placed below. When the water stopped I pulled out the element and was surprised what a state it was in. The metal sheaf had split in more than one place and the whole element was 'swollen' and deformed. There was little scale on it, but the white stuff inside the element had started to come out and that's what caused the water to become cloudy. I attach a photo of the element.

I couldn't remove the temperature probe tube even with the correct allen key and a hammer. The harder I tried, the more bits came out the element and the tube remained fixed. In the end I had to use a new tube which I screwed in to the new element having covered the thread with PTFE tape. I thoroughly cleaned the boiler out (it was free of scale) and then a new 'O' ring and Molykote 111 lubricant and sealant (European name for Dow 111 food safe valve lubricant and sealant) to seal the new element in place.

I didn't want the new element to start heating in an empty boiler, so I kept the element disconnected, turned the machine on, and let the group boiler fill up. Once full I connected the element up, and as if by magic the Mini came back to life!

Thanks so much for all your help and that of La Spaziale UK who have given me (as a novice in repairing coffee machines), so much help, encouragement, support and prompt arrival of spare parts.

[Endo]

Glad to hear all is fixed. Seems like a busted element. The white stuff inside is MgO. It surrounds the inner heating coil and seperates it from the outer shell (the part that split).

You can read about the side effects of MgO here. (Don't worry, it's well tolerated).

http://www.drugs.com/sfx/magnesium-oxid ... fects.html