Capillary Fire Valve - technical query

[Rollerball]

The coiled part of the capillary fire valve on my oil boiler runs alongside the cladded part, therefore it's sandwiched between that and a side panel.

While looking into a problem I removed that side panel and the coil was briefly snagged in the process - I'm pretty sure that I didn't break it but would I know about it if I did?

What happens if the coiled part is broken? Does it automatically shut off the oil feed to the boiler
or does it just not work in the event of a fire?

The boiler still works okay.

 

[Terrywookfit]

Test it with a kettle and thermometer / pyrometer!

 

[Rollerball]

How exactly do I do that?

 

[Terrywookfit]

Fill kettle.
Put sensing phial in kettle.
Put thermostat / Pyrometer probe in kettle
Check cut off design temp of valve.
Turn on kettle and check valve trips at design temperature.
Hope that valve resets when cooled. Occasionally they don't !!!

 

[Rollerball]

Thanks

 

[oilhead]

If you had broken the capillary, it would trip the valve. They are designed to fail safe.

 

[Rollerball]

I see, thanks. So as the boiler is still working all is good.