Join Date: Jan 2008
Location: Bangalore, India
The Solenoid commonly used is normally closed. That is when there is no power it will not allow CO2 to pass. The solenoid is attached to the regulator that gives an output pressure between 20 and 40 PSI. So if a solenoid fails due to over heating of the coil, ideally CO2 stops. if it remains open there is not much pressure to cause the cylinder to become a rocket motor.
If there is a short circuit and causes sparks, it is a fire hazard.
The solenoid cannot fail and cause the cylinder to go flying. This is only possible when of if there is catastrophic damage caused to the Regulator. This means you dropped the CO2 cylinder breaking the regulator, or hit it with a hammer or something similar. Just ensure there is ventilation to keep the temperatures down.
I have had solenoids fail multiple times in the last 10 years of using them.I never had a problem. They just shut down.
Assume the solenoid stays open after failing.
If the solenoid fails and you use a "needle valve", The fish are still safe as it will not allow lots of co2 into the tank.
If you use a "flow control" instead of a needle valve, then there could be a large dump of co2 into the tank.
Both the Needle valve and Flow control look very similar externally. So its easy to mistake one for the other.