Is my Vaillant PCB dying?

[Roddy Young]

My Vaillant ecoTEC plus 618 display is always illuminated - previously it would go dark until I turned one of the temperature setting knobs.

Not only that but now the temperature shown is flickering irregularly around the preset temperature (70°) and also flashing back to the outgoing temperature eg:

69, 70, 69, 70, 44, 45, 69, 70, 44, 70, ...... and so on.

Should I be anticipating a huge bill for a new PCB....or just a new temperature sensor somewhere?

Any ideas?

Thanks for any suggestions.

Roddy

 

[ianmcd]

usually PCB

 

[Roddy Young]

Oh dear...... time to get the bank account in order!

 

[ianmcd]

They are not overly expensive compared to some

 

[Roddy Young]

As a born miser, I suppose I just hope everything will run happily forever without maintenance.
But it is 9 years old so that's not too bad.
Thanks for your help though.

 

[ianmcd]

have a look at Vaillant Fixed price repair, you are just about at the limit, they cover boilers up to ten years old, the one off cost covers labour and parts and comes with a warranty

 

[Roddy Young]

Many thanks, Ian.
I'll look into that.
Roddy

 

[mattylad]

Probably a dry joint because they used lead free solder.

 

[ScottishGasMan]

Yea, sounds like PCB on its way, +1 for fixed price repair, probably a little more expensive than getting a local gas engineer to replace it, but they also will probably find some other issues and if so will deal with them at the same time.

 

[Roddy Young]

Thanks for your replies. Luckily it hasn't stopped yet.....maybe tomorrow!

 

[Roddy Young]

I arranged for Vaillant's fixed price repair. Yes, it's not cheap at £285 but that's the first repair in 9 years and a PCB alone is the best part of £180.

The chappie diagnosed within seconds exactly what you'd said - dry joint on PCB and promptly replaced it.

I was very impressed with him - not only a van full of parts, but he had some really interesting tools such as a gas leak checker and a battery powered pre-set air pump to refill the expansion vessel.

Wearing his mask, friendly and very competent. Happy to chat as he worked, explaining what he was doing.

He showed me that there are 2 memories and changing just one of either PCB or display unit maintains the settings.

In ours, d0 and d19 were reduced to suit the underfloor heating's low flow demand.

Thanks to everyone for your advice.

Roddy

 

[winston1]

The chappie diagnosed within seconds exactly what you'd said - dry joint on PCB and promptly replaced it.

Why on earth did he not resolder it. Worked on TVs for years and never replaced a PCB for a dry joint. Most TV guys can resolder a dry joint so it won't fail again.

As for £180 for a PCB that probably costs a fiver to make!

 

[Gasguru]

I would be very surprised if a modern Vaillant pcb had a dry joint. I've removed various components on these boards and the leaded components are a very tight fit (almost a press fit) and the holes are plated through.
Broken joints are very rare nowdays. Pcb manufacturers of the past like Enertec almost designed the boards to fail with undersized solder pads/single sided boards/over heated components/uncompliant wiring.

 

[denso13]

Why on earth did he not resolder it.

Because it would still cost £285 for the fixed price repair. I know what I'd want as a paying customer.

 

[Gasguru]

Compared to other manufacturers Vaillant pcbs are pretty flakey with some poor design areas..