20/21 blocking alarm

[MichaelS]

Well, I'll be dealing w/ the 20/21 alarm issue today it looks like. Glad I've only a couple things on my plate today. Shame it's the weekend though as I'll have to wait until Mon. to call CCS for parts.

My machine was purchased less than 2 years ago though so it is in warranty fortunately. Just inconvenient to take it apart and troubleshoot. time to find that multi-meter, lol.

Stay tuned....

[chas]

Is it the alarm where 20/21 stay on or the alarm where they blink?

[MichaelS]

When I first discovered it this morning they were solid (5am - I leave it on 24/7), so I unplugged the machine for 15 minutes and then plugged it back in to see and they blinked for 5-6 times at which point I unplugged it again. I've not plugged it back in since that attempt though, so the answer to your question is both I guess

michael

[chas]

As you've no doubt read from the User's Manual, since you have seen the lights be on steady and also blink, it could either be a bad temperature sensor or a bad triac board (unless you have one of the newer S1's with the SSR rather than the triac.

I think the way that the S1 thinks the triac/SSR is stuck on is when the temperature sensor indcates that the temperature in the boiler is >140C. However, a shorted temperature sensor also indicates that the boiler temp is >140C. Frankly, before you got to that point I think the OPV would be opening up and flooding water into the drip tray and I'm sure you would have mentioned it had that happened. So it is probably a false positive indication. The first thing I would do is ohm the temperature sensor and see if it is shorted (0 ohms). The temperature sensor also bad if it is open and reads infinity ohms but the other symptoms you mention don't match this failure mode.

If the temperature probe checks out and you have an older triac S1 version, the other test you can do is to completely swap the wire connections on both triac boards. If you do that and the group triac board is bad, the group boiler will heat up just fine after the swap but you will eventually get lights 19-20-21 coming on indicating a steam boiler error. In this case you can press the Boiler button to turn off the steam boiler. This may prevent the problem. If not you can pull the wires off the bad triac board and still get espresso but no steam until you can get replacement parts from Chris.

Good luck. Let us know how things turn out.

[MichaelS]

Superb insight Chas, thank you. I'll give that a shot, but a new twist is that after letting it sit 8 hours, I've just plugged it back in and it's coming up to temp normally - group head already hit 93 and the boiler is heating up now (I don't leave the boiler on, only turned on when necessary).

I'm going to let the boiler come up of the way up and see if I get another error or not. I've no doubt that there is an issue, but whether it's intermittent or not may make things a bit more interesting. Either way, I'll be talking to CCS on Monday and see what they say. I'll also do the probe test as suggested to have that data in hand, as I'd wager the techs there may ask also.

Thanks again!

michael

[MichaelS]

Well, back to this morning - solid 20/21. I have disassembled the machine, but now I need to look up the pictures and ensure I know which wires to test etc. First time I've been inside the V, want to both learn and avoid damage :)

michael

[chas]

It may be a pain but it's a good thing to pop the covers off once or twice a year to clean and inspect the innards. You'll want to pay close attention to the wires - are the connectors tight, is the insulation especially on the steam boiler leads where they connect to the boiler elements not burned nor the wire corroded? Are the plastic insulators over the connection in good shape and not getting brittle?

Also, check the internal plumbing for signs of slow drippage. If you have the measuring tools, this is also the time to check the adjustment of the group pressure and the group expansion valve. Adjustment is covered near the end of the User's Manual.

[MichaelS]

It's okay, I do believe in a good maintenance routine. I've got it apart now and the wires, connectors, and fittings all look immaculate. No cracking, great flexibility where appropriate,and tight connections. There are a couple of leak location possibilities, but given that there is residue, I'm wondering if that's even from my water (the reason I mention this is that literally there is no film / residue in 9 years in my shop sink in the garage... we have unbelievably clean water as far as residue / build up is concerned).

That said, I'll check the triacs a bit later and see - though I suspect I'm going to find the boiler group temp sensor is good and the group head has gone bad. I'll post my findings.

stay tuned..

[MichaelS]

spoke with service today, simple test by moving the probe leads from boiler to group allowed group to heat up. They are sending me a new group temp sensor which should fix the issue I hope.

Easy repair too from what I can tell.
Thanks again for helping Chas - will post conclusion if it does indeed fix it.

michael