Very loud steam boiler release

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TCStuckey3

Very loud steam boiler release

Post by TCStuckey3 »

Hey everyone,

Question for the people on this board wiser than I. I've had my VII for about 4 or 5 years now and have never had a problem. The other day something happened for the first time. I found that the steam boiler was off, and I never turn it off. I don't know if my wife turned it off by accident or if it went off on its own. So I turned it on and a few minutes later there was a VERY loud pop with a steam release. I assume this is a pressure release valve on the boiler. A few days later the power went out so the VII went off. I turned it back on when I got home and the same pop and hiss happened again about 30 mins later. Scared the hell out of everyone in the house. So it's never happened before and now twice in one week. Is this a sign of impending doom? Any help would be much appreciated. Thanks!

Tommy
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slo
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Re: Very loud steam boiler release

Post by slo »

Just a completely useless quick note to let you know that it is nor because you did not get a response that we do not care... It is just that I do not seem to be wiser than you!
Can you give more details? I just cannot understand the scenario. We are not talking about the vacuum breaker here, right?
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster

I have a serious problem ... Can you guess what?
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chas
Vivaldi Dreamer
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Re: Very loud steam boiler release

Post by chas »

I saw your note while I was on the road but it's not easy to pound out a sufficient response on a cell phone.

You'll need to do more experiments and provide some additional information in order to be able to narrow down exactly what is going on and what the probable cause is.

1) Have you removed the top cover so that the top of the steam boiler is exposed and verified whether the Over Pressure Valve on top of the boiler is popping open or whether it is something else?
2) Does the steam boiler pressure go no higher than the top of the green or does it go well up into the red; i.e. significantly above 1.3bar
3) If the pressure does go up into the red, does the boiler lamp stop blinking indicating that the controller board thinks it has shut off the boiler or does the boiler lamp continue to blink?
4) If the pressure goes into the red but the boiler lamp stops blinking, this indicates that the controller board has attempted to turn off the triac board which should shut off power to the steam boiler. If you have an AC voltmeter test the two power leads on top of the boiler to see if they still have ~120V applied when the boiler lamp is NOT blinking. If this is the case you probably need a new triac board.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
TCStuckey3

Re: Very loud steam boiler release

Post by TCStuckey3 »

Guys,

Thanks for the responses. I'll see what additional info I can give. I'm just not familiar with the detailed anatomy of the machine so I don't know about the valves and such that are in play. I'm actually very good with mechanical work, I'm just not educated about boiler/pressure systems.

I haven't removed the top so I don't know about the over pressure valve. This seems to fit the scenario, though. To recap: this has only happened twice, both times it was about 30 minutes or so after the steam boiler was turned on from an off state. This is unusual because I keep the machine and boiler on 24/7. The two times this happened were the only two times the steam boiler has been off in a long time. About 30 or so minutes after turning the steam boiler on there was a loud noise and steam release. I was looking at the machine when it happened once and steam came out of the top of the machine during the noise. Seemed like a valve release for being over-pressurized, but again I just don't know the anatomy and if that is indicative of a problem. It never happens during the on/off cycling of the boiler while always on. Only when turned on from off.

The steam boiler pressure sits just in the red. I would say around 1.4 bar. But this is during normal cycling. I wasn't looking at the gauge when the release occurred. Cycling seems to proceed normally without problems in the constantly on state.

Is this just something that happens sometimes and it's just normal safety measures? Seems unlikely since if this happened every time it was turned on in a household that turned it off every day those people would be frazzled waiting for the startlingly loud pop to occur every morning! Or is the steam boiler pressure set a little high and it's overshooting when turned on from off, causing a safety release? Can I/should I lower the pressure setting on the steam boiler? Is that do-able? Thanks for the help!
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chas
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Re: Very loud steam boiler release

Post by chas »

Since it is intermittent as you have described, it is probably NOT the controller or the triac board. The fact that the "normal" pressure is about 1.4bar, which is a little up into the red, is the only thing that is suspicious. This is NOT adjustable on the S1 or V2. All you can do is replace the temperature sensor which is what I would recommend.

The other thing you might want to do - just for general maintenance - is to pull out the water level sensor. By now it may have some mineral build-up on the last inch or so of the sensor probe. Soak that in vinegar for a while, scrape off the minerals, then reinsert the sensor. If there is a build-up, the water level may be a bit higher than it should be. The boiler should be filling up just to the point where the water level touches the end of the sensor probe tip. If there is a lot of mineral build-up, the boiler may be filling until it reaches the non-mineral encrusted part of the probe.

I doubt only doing the latter will fix the issue, but you might as well try that first since it is free; whereas a new temperature probe is probably $25 or $30.

There is also one more possibility which could happen if the boiler is overfilling due the reasons I mentioned above. When the steam boiler nears boiling, the steam pressure inside pushes the vacuum breaker valve closed. If the water level is too high, you could get a momentary gush of steam/hot water out of that valve. If that is the case, then the steam boiler pressure may not actually be getting too high. Without you being able to visually tell which valve is releasing the pressure or whether the pressure is going way up into the red on the gauge before the pressure releases, we can't really narrow it down to which is the culprit.

So I guess the bottom line is to demineralize and reinstall the water level sensor first to see if that fixes the issue. Even if that does fix the issue, should your normal steam boiler pressure still run at 1.4bar, you may want to replace the temp sensor anyway as most S1s run 1.2 - 1.3.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
TCStuckey3

Re: Very loud steam boiler release

Post by TCStuckey3 »

Thanks. I'll give it a shot!
gene

Re: Very loud steam boiler release

Post by gene »

Tommy:

I'm really curious.

Would appreciate your posting a follow-up so we can all learn from this.

Did you soak it in vinegar, clean it and reinstall and this took care of it or?

Has the steam valve popped any more?
Thanks
gene
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