Help it's freezing !!! - Ignition (Spark) Generator failed??

[cardob00]

Hey Folks,

I have a Potterton Netaheat 16-22 MKIIF Boiler that failed a number of times in prev years - all cases was the spark generator which were replaced by Boiler engineers. Have a feeling they were reconditioned which caused them to fail almost every yr!

Boiler is not igniting today and I am 99% is the same. There is a loud click as usual but no constant clicking sounds - am I correct its the Spark gen?

Ignition generator is VERNITRON LTD - part number : 407/1/72637/010.

1) Are these readily available from any good high street type heating suppliers in NW London area?

2) How do I know its a brand new one and not reconditioned ?

3) If I could buy it - is it pretty simple to replace?

As ever your help is greatly appreciated and my very cold 2 small kids too!

 

[gas4you]

These are dangerous boilers for a diyer to work on.

Fan and aps needs checking first.

 

[corgigazza]

for spares try http://www.curzoncare.co.uk/ or http://www.partscenter.co.uk/ but the gas valves fail on these also the sparking bracket corrodes giving a poor spark.Can u see the pilot allight through the window

 

[pannierstan]

I would suggest that the main reason for the generator failing so often is that the spark wire has broken down and although the pilot and boiler continue to work fine the generator is continually sparking!
The leads become high resistance due to break or more likely rust at the connection on the spark probe and the spark will jump the gap but the DC current used to stop the generator sparking will not pass the other way

If the lead is replaced you might find the generator will last another 15 years like the first one did and that boiler is probably good for another 15 anyway.
I always carry one aswell as the genny and only did one the other week.

Stan

 

[cardob00]

CorgiGazza and Stan, thanks for the replies.

There is no pilot light on but I think it only lights when you turn on heating with the initial loud click (what is that by the way)? Or am I wrong ??? Should the pilot light be only all the time with a Netaheat 16-22 regardless of the spark generator working or not?

Also, yes when the boiler is working, you can continually hear the spark generator going - not sure if it ever stops - perhaps after 5 mins...

I'm happy to buy a new Spark Gen as there seem to be online suppliers & deliver next day or so. BUT HOW do I change it? eg simple as put of electricity, unscrew bolts, unplug the 3(?) clips and replace with new spark gen? I dont mess with boilers really so not sure if this is a safe option....

 

[cardob00]

Ok some progress, I took the plunge! I flicked the isolating electric switch next to the HW/CH control panel which went off. I'm hoping this was for the boiler too! Anyhow, I unscrewed 2 screws holding the the spark generator and pulled out the 3 connecting leads , so simple enough to replace.

Decided to unscrew the actual casing to look inside out of curiosity. Saw 2 wires I think from the coiled (solenoid?) - One thickish red and the other EXTREMELY thin black one - not sure if its even a wire - couldn't see a flex round it even. I barely touched the black one which just disintegrated - so now not sure if this was simply extremely delicate or worn completely.

Well going to pick up a new one £50 thought it's worth a try as I couldn't hear it clicking at all. May be wrong but if I can replace it then it's just the part wasted.

 

[bengasman]

Netaheat is a positive pressure boiler, if you do not know how to test the combustion chamber, you are taking a serious risk. Get an rgi to look at it

 

[cardob00]

Hey just to say that I bought a new Spark Gen for the netaheat 16-22 from a local heating supplier and hey presto it works. So yet again it was the Spark Gen - this is now the 4th I think in about 8 years. As I suspected it was easy to remove - 2 screws holding it in place and 3 push/pull clips to the PCB. I replaced it in 5 mins and now works.

However.....can someone tell me whether this Spark Generator (or others in general) are supposed to carry on clicking/sparking whilst the boiler is on? Clicks (Sparks I assume) stop after the boiler auto stops and starts again the clicking when boiler firesup. Is this normal - I would think that it should stop clicking once "full burn" has started? Perhaps this is the issue and why the Spark Gen is wearing out.

Whats the avg life cycle of a spark gen for a NetaHeat 16-22?

 

[cardob00]

Just wondered if anyone could help re my question above re my Netaheat 16-22 bolier

1) Should the spark generator by "clicking" the entire duration when the boiler is on "full burn" ie on. It goes off when boiler auto stops - then starts again when boiler refires up..is this normal?

2) How long do these spark gen's work normally?

Thanks.

 

[sooey]

Read pannierstan's post.

 

[Agile]

I dont expect it to carry on sparking!

I expect the generator to last well beyond my guarantee period of one year!

In fact I expect it to last about 10 years!

Tony

 

[ChrisR]

No it shouldn't keep sparking - that's why yours are so short lived. Mine's 23 years old.

 

[cardob00]

Great thanks for the replies...as I suspected it shouldn't carry on sparking then- seemed weird.

So I'm assuming to check why this is happening is a lid off the boiler by Corgi Eng rather than the pull out cover below only to get to the spark gen and PCB etc which I'm capable off? Wondering if it could be the PCB perhaps that is not telling the Spark to "stop"...

 

[Agile]

I would expect an electrode lead or PCB fault.

Tony