They dont make those.

[Kayos]

I know this is is a very common failure mode & suspect it is caused by the back EMF when the valve closes. Also observed it on the bridge rectifier feeding the gas solenoid valve, but being technicians with limited service time board change is the order of the day
RonA

I'm sorry but appliances with an on/off solenoid valve do not have this as a very common problem or indeed bridge rectifiers, they use AC solenoids

A modulating boiler has a very different mode of operation, back emf doesn't interfere with the boards.
Boards do fail, it is a consequence of more complicated appliances. Time limited is often correct, a good engineer will diagnose a PCB quickly but is unlikely to have the skills or equipment to repair it.

Modern boards also have to be designed so component failure external to the board doesn't damage the board, in theory makes diagnostic easier and less costly, but further adds to the complexity

 

[lotus_esprit_s1]

I bought a new set of 5m oxyacetylene hoses from one major online supplier last year. They sent a pair of Esab hoses, one of which had been cut down to 5m from a longer hose and the cut end crimped with a double ear crimp, which leaked profusely. I was absolutely jumping and complained only to be told they don’t sell Esab hoses so must’ve come from somewhere else, despite producing receipts. I recrimped it myself properly in the end

Stupidly I forgot this and last week ordered a machine from them online and yet again they are a nightmare to deal with punting me between departments and have yet to return any phone call.

 

[RonA]

I'm sorry but appliances with an on/off solenoid valve do not have this as a very common problem or indeed bridge rectifiers, they use AC solenoids

A modulating boiler has a very different mode of operation, back emf doesn't interfere with the boards.
Boards do fail, it is a consequence of more complicated appliances. Time limited is often correct, a good engineer will diagnose a PCB quickly but is unlikely to have the skills or equipment to repair it.

Modern boards also have to be designed so component failure external to the board doesn't damage the board, in theory makes diagnostic easier and less costly, but further adds to the complexity

The boards on the very latest boilers may use AC solenoids but previous generations like the Vaillant + others utilised a 240 to 36v transformer & then through a bridge rectifier to end up with 24V DC (half wave rectified) to operate the gas valve. I’ve seen quite a number of boards with the soldering around the connections of the bridge rectifier displaying a black ring round the connection where its failed. Most don’t seem to employ snubbing capacitors so most likely cause to my mind would be emf generated when the gas valve solenoid is closed.
RonA

 

[Seadog]

I would suspect that the failure is more likely due to mechanical stress. Now that lead-free solder is universally used you have a joint that is less forgiving.

 

[Kayos]

The boards on the very latest boilers may use AC solenoids but previous generations like the Bosch Worcester range + others utilised a 240 to 36v transformer & then through a bridge rectifier to end up with 24V DC (half wave rectified) to operate the gas valve. I’ve seen quite a number of boards with the soldering around the connections of the bridge rectifier displaying a black ring round the connection where its failed. Most don’t seem to employ snubbing capacitors so most likely cause to my mind would be emf generated when the gas valve solenoid is closed.
RonA

So you are talking about the ones that use a modureg, essentially a 2 stage solenoid to give different gas rates. A capacitor would store electricity and prevent the solenoid from switching high/low or worse case switching off

You need a full understanding of how the appliance works before you can say the design is wrong

 

[droopsnoot]

I was absolutely jumping and complained only to be told they don’t sell Esab hoses so must’ve come from somewhere else, despite producing receipts.

I bought some carbon brushes to repair a lawn mower from a brush seller on eBay, they weren't the size he'd said they were so I emailed him to ask if he'd put the wrong ones in the envelope. I didn't imagine he'd start off with "send me a photo and I'll try to work out where you bought them from" and go downhill from there, including "I've never sold brushes that size", the implication being that I was trying it on. I raised an eBay ticket and he refunded me, the first time I've had to do that. After that, I read his feedback and found that he's got form for that kind of thing.

I have a little sympathy for some of these people, when they say "they don't make those" what they mean is "we don't sell them" and perhaps don't have the freedom to be able to spend time looking around for a product that they're not going to make any money on. They don't spend time (or perhaps aren't allowed to spend time) helping you find a supplier and don't take into account the possible loss of future business. I've avoided places for years based on that kind of "can't help" attitude, or other minor slights. I avoided B&Q for years because in my first job the boss was making a counter / worktop and wanted to stick down the top, sent me to B&Q to get a tin of glue and they wouldn't sell it to me in case I sniffed it all on the way back.

 

[ukracer]

Not allowed to repair PCBs, it's classed as a modification.
Yes, I know but BG got seriously shafted for repairing a design flaw on a PCB that was well known to fail and produced a better version. The manufacturer took them to court and won.

Diabolical. The world's gone mad.

 

[RonA]

So you are talking about the ones that use a modureg, essentially a 2 stage solenoid to give different gas rates. A capacitor would store electricity and prevent the solenoid from switching high/low or worse case switching off

You need a full understanding of how the appliance works before you can say the design is wrong

I say as I see, having seen numerous boards all with a common fault it would suggest something wrong with the circuit design. Engineering design errors occur everyday, check out the millennium bridge saga.
Snubbing capacitors are small value & only designed to absorb the sudden back emf & if properly sized would not prevent the solenoid closing.
RonA

 

[Kayos]

Diabolical. The world's gone mad.

I kind of see the manufacturers point.

"Faulty boiler kills family" full front page spread
"Boiler PCB repaired by engineer" tiny text, 3 pages in
Way of the world, sadly. Also the fact they issued an updated PCB that did not fix the underlying issue but BG did probably ****** them off

 

[Kayos]

I say as I see, having seen numerous boards all with a common fault it would suggest something wrong with the circuit design. Engineering design errors occur everyday, check out the millennium bridge saga.
Snubbing capacitors are small value & only designed to absorb the sudden back emf & if properly sized would not prevent the solenoid closing.
RonA

I guess my industry knowledge and yours must differ at this point, so respectfully I suggest we agree to disagree

 

[Blobber]

I bought a new set of 5m oxyacetylene hoses from one major online supplier last year. They sent a pair of Esab hoses, one of which had been cut down to 5m from a longer hose and the cut end crimped with a double ear crimp, which leaked profusely. I was absolutely jumping and complained only to be told they don’t sell Esab hoses so must’ve come from somewhere else, despite producing receipts. I recrimped it myself properly in the end

Stupidly I forgot this and last week ordered a machine from them online and yet again they are a nightmare to deal with punting me between departments and have yet to return any phone call.

Name and shame so the rest of us dont get stung!

 

[bricol]

Name and shame so the rest of us dont get stung!

No! If its a big company with a legal dept, or resources to find a legal person . . . the bloke who runs this website probably wants to keep his house rather than pay out damages . . .

 

[chunkolini]

I had been using a well known Welsh steel supplier for years.
I went to order some black finish hot rolled 8mm mild steel bar. Stuff I had been using for years and bought through them.
'No sir we have never stocked that, cant get it' Bloody hopeless

 

[julianthegypsy]

I had been using a well known Welsh steel supplier for years.
I went to order some black finish hot rolled 8mm mild steel bar. Stuff I had been using for years and bought through them.
'No sir we have never stocked that, cant get it' Bloody hopeless

I've had the exact same experience. Stuff I've bought regularly. Pain in the .....

 

[graffian]

I had been using a well known Welsh steel supplier for years.
I went to order some black finish hot rolled 8mm mild steel bar. Stuff I had been using for years and bought through them.
'No sir we have never stocked that, cant get it' Bloody hopeless

I had forgotten about the steel.
Parkers used to do the 'we have never stocked that' for 80x5 flat bar.
I was invariably palmed off with some free lengths of 100x6 and had to go back the next day for my 80x5!
But as it happened regularly I wasn't at all bothered.

 

[Farside]

If there is one thing that boils my wee its the statement by suppliers & shops, "Cant get those, they dont make them anymore".

Or another favourite, "No demand for them any more. Funnily enough, you're the third person this week to ask for them."

Regarding "We've never stocked that" storemen; a local electrical wholesaler I've been dealing with for years and knew the staff well, I went in and asked for some flexy conduit. The bloke who served me was a new face, who trotted out the infamous line.
I pointed out I'd stood at that same counter two years before and bought ten metres of it, but that was from someone who had a clue.
I went up the road to the other wholesaler in town and got it no bother. Since then I've not set foot in the first one.