Potterton Netaheat 10/16 controller burnt?

[Mike Tomlinson]

En el artículo , Roger Mills escribió:

Some cheap relays and wound components (inductors, transformers) come out of the factory with pins that aren't tinned. Those will appear to solder ok but actually have made a poor joint where solder surrounds the pin but doesn't properly bond to it. I'll give you one guess where the relay at fault in the OP's board was made.

Sometimes it's necessary to take the component off the board, rub the pins/legs down, tin then re-fit them, to ensure a decent joint.

I'm pretty sure that was the cause of the original fault causing the arcing around the relay pin and subsequent charring of the OP's original board.

[T i m]

I'd just like to say a 'big thanks' to all those who offered feedback, advice and info on this issue.

Before re-connecting the controller I measured about 79 ohms across the fan so not far off Chris K's 68. ;-)

Running the fan directly from the mains showed about 275 mA so well inside the 1A main fuse limit.

When re-connecting the gas valve I found one of the threads stripped on the connector so I had to take the one from the original board . Thank goodness for my little 'iroda Solderpro 50k' gas iron. ;-)

Powered it all up whilst monitoring the current on the main fuse and saw it ramp up to just over ~300mA.

Fan > igniter + gas valve pilot > pilot > igniter off > main burner on and away we went. ;-)

I ran it with the cover off the controller till the CH + water were up to temp and the boiler shut off. Powered down and made sure none of the components were running hot then boxed it all back up and was then given full access to the biscuit tin. ;-)

So, thanks again to all from one warm old dear and I.

Cheers, T i m

(It may well be that she's just outside the eligibility for the Warmfront deal but we will still check it out).

[meow2222]

solder oxidises easily from excess heat. Lead oxide's good for nowt.

NT

[Tim Streater]

That should be " ... one warm old dear and me."

Now, before getting me coat:

1) WTF is ??

2) Kudos to you for persisting with this - looking after an old dear - that's a good thing you have done there laddie.

[T i m]

Hey, I was talking about grandma, not grammar. ;-)

;-)

Why thanks. She's a good old salt, forever thanking us for the slightest things and it's really / actually nice to be able to make her life easier / more comfortable, any way possible.

She is suffering (and has to take morphine regularly) with bad ulcers on both legs to the point where she may have to have both amputated.

In spite of that, no sooner are you in the door then she's trying to get up offering tea and food.

Whilst she always seems to have someone (friends and family) ringing or texting her, she really enjoys real company and my Mrs tries to go over there as often as possible, especially if she believes she hasn't had any other visitors that day.

It's no hardship to either of us to help whatever way we can because it's easy to help nice people. ;-)

Tonight we were talking to her about the idea of getting more use out of her mobility scooter. It's kept at the bottom of the garden with a fairy tricky access to the outside world (not such an issue where her husband was still alive and would bring it round the front for her). I asked her if there was any reason and / or if she would like the buggy out the front in one of these secure stores so she could get at it easier and her reply was 'Oh yes dear, that would be so nice if I could have some mobility back ...'.

How great would it be to be part of giving that to someone ... ;-)

(Anyone any experience of these secure scooter stores that have a lift up lid (I think they may be raised electrically), again, might be something she could get financial help with)?

This sort of things possibly?

Cheers, T i m

[Vir Campestris]

I'm not going to read the entire thread but has anyone mentioned cetltd.com?

Andy

[Roger Mills]

I don't think so, but: a) The OP obtained a (more or less) working second-hand PCB from somewhere else b) I doubt whether Geoff would have accepted the old board because it probably wasn't repairable

[T i m]

'More or less working' ... I like it. ;-)

I wondered if Geoff would chime in (I've seen him doing his wizardry in person ) so I'm guessing, if he saw the thread that it probably wasn't worth his time under the circumstances.

And with a 'more or less working' replacement for 1/4 of the cost of the cheapest new one is was worth trying, even if it too went up in smoke (especially so in fact).

Had a replacement not been available I may have repaired the old board (I've repaired worse) if only as a test and could have completely re-populated anything that may have failed for very little.

Anyway, it still seems to be working ok. ;-)

Cheers, T i m

[Roger Mills]

I was referring to the fact that you had to replace one of the connectors which had a stripped thread.

[T i m]

And a fuse missing, yes, I know, and I liked the description. ;-)

Cheers, T i m