Solenoid Stuck Open??????

chunter

I'm curious how many divers have experienced a solenoid failing in the open position. I have had it twice on two different units and am feeling like the guy who got struck by lightning twice. Neither pushed my PO2 above 1.8 or 1.9, but it is pretty worrying. Both times I was at about 110 feet and am glad I wasn't deeper.

So, I have created this poll. If you have had solenoid issues, feel free to list the type of unit and circumstances. Possible cause would also be of interest.

Aloha,
Charlie

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Gilles

Failed closed as a result of corrosion caused by insufficient drying out of Swagelock QC when connecting O2 feed.

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mempilot

While the solenoid itself didn't fail, the battery providing voltage to it took a dive during the dive, leaving the solenoid quiet. The predive no-load and load voltage were within spec. This had the same effect as a failed closed solenoid. I now use a higher baseline voltage to determine whether a cell pack gets tossed.

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cys

Solenoid failed closed during a dive when I was at about 50'. Unit was a HH-Kiss, and the failure was due to corrosion. My suspicion is that corrosion on the outside did it in. While there was plenty of corrosion to be seen on the outside to support this interpretation, I can't rule out subtle corrosion on the inside leading to the observed result. Remedies I have pursued are adding a swagelok filter (to protect the inside) and changing environmental sealing methods for the solenoid (to try to protect the outside more).

dave t

I have had solenoid stuck open twice on my inspiration but I was playing with running very low IP on the o2 first stage which would probably be the cause.
I also had an orifice fall apart on my KISS which gives the same end result.

best

Dave

Pelagian

Failed closed due to a low battery on my Meg

Displays still worked, but not enough juice to fire the solenoid.

Changed the battery and no problems since.

I have also witnessed a stuck open solenoid on a another team's Meg. Solution for that, was to disconnect the feed from the head.

Cheers

Seb

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Drmike

Stuck open on mk15.5, rust due to water getting in qc when connection.

1st problem in a series of problems that saw me knowingly breathing 8bar ppo2 .

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lancsman

I was lucky as when My Meg went for service, including the addition of a filter, there was dirt in the pipe which could easily have jammed the solenoid.

I am not sure why they added the filter but !

Mark

sddiverrob

Solenoid stuck open at 70' on my old eCCR with aftermarket electronics. I heard the solenoid open and not close and the HUD started flashing red. Sent the electronics back to be inspected and one of the solder joints had broken free in the handset. Looks like it wasn't protected very well and got banged around while traveling. At some point between the entry and descent it must have broken free and made enough of a connection to open the solenoid and keep it open. It didn't stick open until I had started swimming along the wreck.

Electronics passed all tests on the boat including maintaining the setpoint while pre-breathing. After a not so cheap repair, worked flawlessly. Protect your handsets!

Rob

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Abbo

I've had that too. My first reaction to your comment was that that's hardly a failure of the solenoid - any more than failing to put gasoline in your car is an engine failure. But I must admit I'm not very happy with the battery situation on the Meg. It forces you to choose between 3 rather unattractive options: paying exorbitant rates to send purpose-built battery packs Around The World In 80 Days from Seattle, soldering a pack myself, or using off-the-shelf batteries that have dramatic falloffs in voltage at the end of their pitifully short lives. I do think that a re-design of the battery compartment is merited, to help you to connect several cells in series in a battery holder, without your having to solder them together. With some off-the-shelf batteries, the voltage drop-off by the time you get to 6.5v can drop to a level that it can't run the solenoid within one dive - and it does that without tripping the low-voltage warning. Not a major problem, but a little disappointing in what is otherwise an unrivalled piece of kit.