Gas controls questions

[spanners1967]

I failed my Level 3 gas assessments on gas controls. Working as a new installer I have been told that this can be a common pit fall for first assessment candidates. I am resitting on 6 August .Anyway, I will put some of the questions I had up here , with some answers i think are right and would appreciate any comments or feedback... thanks in advance

1 Liquid expansion FSD- what is likely fault if gas flame remains on low?........
FSD faulty?

2 Liquid expansion thermostat- what is likely fault if gas flame remains on high when required temp is reached?..... Phial not located correctly

3 Multifunction valve- what's most imporatant safety function of these? .... The FSD?

4 likely fault when cooker tap is turned to simmer and burner goes out? ..... small drilled hole in gas tap blocked

5 Thermo electric valve- likely fault if thermo electric valve does not close withgin 90 seconds?... valve jammed?

6 electro thermo - likely result of thermostat phial/probe not correctly positioned ? burner remains on high?

I have most of the other fairly sussed but would greatly appreciate any comments.

Thanks

:nopity:

 

[chris watkins]

1 Liquid expansion FSD- what is likely fault if gas flame remains on low?........
FSD faulty?

Page 336 L3 JTL book = thermostat not working / bellows or phial / capillary tube broken.

2 Liquid expansion thermostat- what is likely fault if gas flame remains on high when required temp is reached?..... Phial not located correctly or valve / spring stuck open.

3 Multifunction valve- what's most imporatant safety function of these? .... The FSD (thermocouple) Page 338

4 likely fault when cooker tap is turned to simmer and burner goes out? ..... small gas ways in burner blocked with food / grease (hob) or blocked bypass in oven.

5 Thermo electric valve- likely fault if thermo electric valve does not close withgin 90 seconds?... valve jammed open / spring

6 electro thermo - likely result of thermostat phial/probe not correctly positioned = Pilot will not remain alight when button is released. P334.

Hope this helps & hope I am right, sure the guys will correct anything but have a look in your Level 3 book (not got one ? then get one).

 

[spanners1967]

thanks for the effort Chris, I'll buy one on ebay... my main book has been the orange domestic gas safety book, there's not a lot in that... cheers...