Flame failure device very ‘lazy’

[starman]

Just started using our lpg hob after being out of use for three plus years during refit. 
The gas works fine but we have to hold any hot plate control knob down for 30+ seconds or the FFD cuts in and the gas goes out. Hold long enough and all’s fine. 
Anyone got any clues - fast running out of matches and patience. 

[Tracy D'arth]

Are they all doing it?  If it has been damp, the thermocouples can get damp in the magnesium oxide powder insulation in the coaxial copper "wire". This reduces the current available to hold in the solenoid in the gas taps.

They can be dried in an oven@200 d degrees. but they will have to be removed to do it.

[Jen-in-Wellies]

5 minutes ago, Tracy D'arth said:

They can be dried in an oven@200 d degrees. but they will have to be removed to do it.

If you remove them, can you light the oven? 😆

[starman]

9 minutes ago, Tracy D'arth said:

Are they all doing it?  If it has been damp, the thermocouples can get damp in the magnesium oxide powder insulation in the coaxial copper "wire". This reduces the current available to hold in the solenoid in the gas taps.

They can be dried in an oven@200 d degrees. but they will have to be removed to do it.

Yes all doing it - but can I light the oven good question!

[Tracy D'arth]

5 minutes ago, Jen-in-Wellies said:

If you remove them, can you light the oven? 😆

Yes, having first checked if its a combined oven/hob that the gas taps are not passing gas where the thermocouples screw in.   Good question though, do the oven and grill work normally or have they the same problem?.

 

As I read the first post its a separate hob unit

[TheBiscuits]

2 hours ago, starman said:

The gas works fine but we have to hold any hot plate control knob down for 30+ seconds or the FFD cuts in and the gas goes out. Hold long enough and all’s fine. 

 

That's what I'd call working too hard, not being lazy!