Urgent: Regulator question

[Shane Phelan]

I was just carbing a keg and my regulator has started going up to max pressure and then the safety vent blows, then back up to max pressure and safety valve again. I cant seem to stop it no matter what direction I turn the regulator itself!  I have the taps turned off and its just hissing away at 50psi. 

WTF!   

[Ciderhead]

reg valve may be stuck open, was it frozen after a lot of gas?
remove disconnect so that co2 can vent fully
turn off pressure at your tank fully. turn reg valve fully one way, open main tank valve, vent off, close tank.
fully turn reg other way, open tank again should be nothing coming out until you start to twist reg.

I thought they were a black art until I saw Craig take one apart

http://www.youtube.com/watch?v=5TckoNE1Uro

[Shane Phelan]

Don't know what happened, there wasn't even gas flowing, I put gas into the keg at around 20PSI and then turned off the little red tap. Then I sat down and was pissing around in the forums here. Next thing I know I hear gas hissing out of the relief valve on the regulator which pops the second I touch it.

I cant turn off the pressure from the tank as its a soda stream bottle so the only way is to remove it completely which I have just done but I think I just lost most of the gas. I tried reconnecting it and the pressure guage just flies up to the maximum. I think it is stuck as there is no resistance to the knob when I turn it until it is nearly all the way in (i.e. to the max pressure).

[Ciderhead]

have you ever had beer blow back into it from a pressurised keg that could be keeping the valve stuck open?

[Rossa]

Threads gone?

[Shane Phelan]

Nothing blew back into it and I opened it up and its all dry inside too. I gave everything a wipe down and closed it again but its not any different, the second I give it gas the gauge flies up to 50PSI and then vents.

Threads seem ok everywhere, the regulator is brand new and as never actually dispensed beer before so it should be in perfect condition. I have used it to purge kegs before, so it wasn't (at least not initially) a dud.

[Metattron]

Is your gas bottle upside down?  Forcing liquid CO2 into the reg would freeze it...

[Shane Phelan]

That could potentially be it although I have always had it on its side and there was never a huge amount of gas flowing. Here it is in action:

http://www.youtube.com/watch?v=nYqrBF_RH7M

[Metattron]

It should be upright, unless it has a dip tube but I doubt it on those bottles.  I'd say that's why you have dry ice in the reg.  Clear it out and try it upright.  You may need to defrost it fully first.

[Shane Phelan]

Tried this again with my new 5kg tank, still venting like in video. Even though I have done it twice or three times already, I again took it apart and put it back together again and now it works grand! Don't really know wtf the problem was.

[Ciderhead]

Cold c02 freezing diaphragm?
If it happens again spend €35 with Alex

[Shane Phelan]

That could potentially have been the issue with the Soda Stream bottle but this one was upright.