If it's any interest, I too have a boiler with an SIT gas valve, pic below, also got some plastic on it. One of the solenoids failed a couple of years back, but it went open circuit, didn't short. It failed safe, the boiler wouldn't fire.If a gas valve does not fail-safe its a concern & should be reported to the manufacturer. I remember various bulletins were put out within the UK Defence organisation when a particular model of Honeywell gas valve did not fail safe.
Last edited: