Piezo igniters and HT leads
Situation is we have an old ornamental gas fire basket in the front room where the piezo igniter has packed up and no direct replacements are available due to it being discontinued.
Currently lighting it with a cigarette lighter which is a bit of a faff.
so my choices are
A: buy a new fireplace - not going to happen.
B: buy one of those gas hob igniter things, although access to the point that needs lit is fiddly due to odd angles and ornamental coal in the way
C: what I really want, fit my own piezzo igniter
What I don't understand is how they work with the HT cables. I really want to spark in quite specific place near the underside of the fire basket, but the button near the front. So I'm looking at something like THIS What I don't understand is what do I need to fit on the end of the HT lead, if anything to create the spark at the end furthest away from the button?
Re: Piezo igniters and HT leads
Nothing, just asmall air gap for the spark to jump across the gas outlet.
Depending on the age of the gas fire, there may be a flame failure device, so the igniter lights a pilot light which heats up a thermocouple that holds the main gas supply on.
You need to look at where the existing igniter ht lead ends and position the replacement in the same place. You need to make sure the body of the replacement unit is connected to chassis of the fire as that provides the return part of the spark gap.
Re: Piezo igniters and HT leads
Thanks. To be clear, on the ebay one above, the spark will jump out of the 1/8" spade socket? Would I need to put a male spade in there to have a male type bit at the end?
Had the gas engineer round to have a look at it and the basic gas / thermocouple works fine but is just a bit sensitive, so there is a bit of a knack with timing flicking over from pilot only to fully ignited. Should be fairly easy to position as the old igniter is one of the style that looks like a spark plug
Re: Piezo igniters and HT leads
I know what you mean about the old ignitere - there is a ceramic insulator and the HT lead goes to a spike and the spark jumps to earth through the gas stream for the pilot light. Personally I'd be inclines to cut the existing HT lead to the ignitor head and the lead on the new piezo device and solder them together using some silicone sleeving (or heat shrink) to insulate the join.
The ceramic bit will be perfectly placed (and the tip may have a sharp point to encourage the spark to form there). That way you are preseving as much of the original as you can.
Its hard to give advice without looking at the two ends of the job, but provided any joint is well insulated so the spark doesn't happen in the wrong place, you should be OK.
Sorry for the delay in replying, been away for a couple of days.
Re: Piezo igniters and HT leads
Thanks - wasn't sure if the 'spark plug thing' was the piezo itself or just ceramic. That clears it up. Bit of wire snipping and a use for my heatshrink butt connectors I reckon.
Re: Piezo igniters and HT leads
Looks OK! Let us know how you get on!