Solenoid stuck open, Has it ever happened?

[Millssy]

Hi all,

I started my Mod 1 yesterday and one of the subjects that we have covered is solenoid stuck open.

Has anyone ever experienced this as i am interested to hear what caused it, to me it seemed there is a lot going on that should stop it form happening.

[Nitnab Nhoj]

Yes. For me it was a low battery during an intensive week's diving. I still got the display but had to drive it manually, turning the O2 on and off as I went.

[BTS]

Other than power outage, see the bit numbered 7, this is an iron core if you get a drop of water in there, say through the bit on the head where the O2 hose connects when discounecting the hose from a wet post dive RB, it will rust over time, if it rusts or otherwise gets gunked it will jam.

[Mark Chase]

Common problem on Megs in the 2004 -2005 modle.

Hapened a few times to a couple of Meg divers on our boat They even put a QD on the solinoid feed to avoid the issue.

I had hand set failure on a Hammer Head which resulted in much the same thing. Solinoid just kept fireing in 02 which was a problem at 70 odd M

ATB

Mark

[DiverMike]

Yes. On my mod 1. It was a bit of crap in the solenoid. When I sent my head in for a service my solenoid was sticking - I was unaware of it but it failed checks and was replaced. It had started to corrode inside.
There is a lot you can do to prevent it happening (like blowing gas through your o2 hose before connecting it to the solenoid, and regular servicing but it can happen, it does happen and its worth being able to resolve it in water.

[bottle maker]

It happened to my mate on his JJ

Graham.

[David]

ccr are just waiting for an excuse to kill you. That said the driver still seems to be the bigest problem :-)

[Hot Totty]

Not yet, but I understand its generally crap or corrosion that's likely to stick it open.

[Mark Chase]

ccr are just waiting for an excuse to kill you. That said the driver still seems to be the bigest problem :-)

But to be fair a stuck open solinoid is hardly any drama. Just isolate and flush.

You could bailout to OC or just run the unit by cracking open the 02 feed every now and again to get the PP02 back up.

I had the equivelent of a half dozon solinoid failures on my HH on one dive to 70 odd m.

It spiked the PP02 big time every time it failed but i just flushed it isolated and swam back to the shot with the 02 switched off.

I did 2.5hours deco on that dive with the solinoid jamed and it wasent realy a problem just cracking the 02 open when the PP02 droped a bit. One of the big advantages of inverted CCR tanks.

[Bobanderson]

I had it on a Inspo.

TBF it was my fault. If you don't turn the O2 off before you disconnect the O2 feed to the head, the pressure can dislodge the gauze filter in the fitting. Fluff got it and stopped the valve shutting.

To stop it happening

Always shut and purge O2 before removing connector to head
Check you have a gauze inline
Blow through O2 line before connecting
Don't bit a muppet.

Having implemented all of the above, things are going just fine. The bit of fluff that held the solenoid open was tiny.