Explosive Ignition question/help

[StevenJames]

Hi everyone, great website. Glad I discovered it.
I am a gas trainee and as part of my homework I have been asked to find out and list as many possible causes of explosive ignition as possible. I have the following, but can't think of any others, that I may have missed. Is there any more I have missed off my list:

DIRTY PILOT BURNER/ASSEMBLY

INCORRECTLY POSITIONED PILOT ASSEMBLY

FAULTY ELECTRODE/HT LEAD (INSULATION LOST/BROKEN DOWN)

INCORRECTLY POSITIONED ELECTRODE LEAD

DIRTY BURNER

DIRTY/PART BLOCKED INJECTOR(S)

GAS VALVE PASSING WHEN SOLENOID SHUT/CLOSED
(too much gas through and when boiler "ignites"/re-ginites: Bang)



If I have missed any I'd be greatful for any help

Steve J

 

[transam]

Leaking burner bar on suprima E.g internal gas leak , Neta heat that misse's out pilot stage in ign sequence that a go BANG !! faulty ign sequence !!

 

[StevenJames]

Thanks for your input and help.

By faulty ignition sequence you mean the intermittent pilot is misse dout (fault board)? and hence straight to main/full gas?...

 

[transam]

Yes , it will or can buckle the casing ect , & remember some boiler's neta heat are positive flue boiler's meaning the fan is sucking air in as opposed to , most boiler's , which are negative pressure meaning the fan is sucking the fume's out !!! explosive ign on these boiler's can mean the casing seal leak's with all the resultant consequence's !!!

Suprima burner bar leak , mean.'s internal gas leak in comb chamber , which will than ignite during ignition = explosive ignition !!!

Had the same prob ounce on an open flued gloworm hideaway / halstead buckingham as neta heat , blew terminal off chimney !!!

 

[StevenJames]

Thanks a lot for all your help I really appreciate it.
I know them positive pressure fanned boilers are dangerous, under normal/correct operation if the seals go then POC will enter the room and cause a real problem.

EVen neg pressure fanned boilers will cause incomplete combustuion if the case seals fail as air from the room will be drawn in and interfere with the combustion process.

Need checking with a taper/smoke pen during service and case seals visually examined

 

[ChrisR]

Steve - as soon as you have a GSR number get yourself into the Combustion Chamber (see the sticky post) and find stuff that isn't in the manual!

Low supply pressure, undersized pipework, sticky regulator, faulty pcb not recognising ignition, and on and on.

 

[transam]

You will find that quite a few negative pressure , boiler's are not completely air tight !!! positive pressure boiler's , can be checked with smoke taper , or if it is the front casing seal leak detector will show up a leak when boiler is running another method posted on here was to turn gas off to boiler , run boiler & place smoke pellet near air intake out side , assuming it can be reached .
One of the few boiler's (neg fan) that will not light if the casing is removed or if there is a significant leak on the casing is the Raven heat CSI primary A boiler , as the aps is pressured open by the fan as opposed to most boiler's that use the fan to suck the aps open , casing leak ect & not enogh preeure exist's !!! gone off topic a bit

 

[StevenJames]

Thanks for all your help. I'll look forward to being in the CC when I am GSR!

 

[nickso]

Thanks for all your help. I'll look forward to being in the CC when I am GSR!

don't do it. all the cool kids shun the CC for the gay, backslapping, todger sucking, hawaiian shirt wearing fest that it is.

you will have to listen to lots more of glaziers nonsense for a start, thats probably the biggest reason to not join.