Vaillant VCW-sine 18

[S700JCB]

Hi, my sister has one of these boilers and Vaillant have now stopped supporting it. It has just developed a fault where it will not fire up reliably. When CH or HW is requested the main burner doesn't always light. When I looked yesterday it took 2 attempts ie the main burner lit then went out and then lit on the second attempt. She says sometimes it tries several times but doesn't ignite at all. If she then resets the boiler, it lights.

My guess would be the gas valve - not something I would attempt myself. Does anybody have any other thoughts about the cause and can anybody recommend a Vaillant service engineer in the Manchester area.

Thanks

 

[Agile]

One of my favourite boilers!

But I dont go further north than Brum!

Nor do we give advice on gas related problems on this forum.

It could be flow related and there is a black unit with two small tubes going off to the right. On the back of that is a pin which extends to enable the gas valve.

Perhaps someone on here can suggest an engineer for you.

Tony

 

[compheat]

As the system been worked on recently? if theres air in the system it may stop it firing.
this boiler must be at least 25+ years old, and is one of the best combi's ever made and the first one I ever installed.

 

[S700JCB]

There was a new fan fitted around January but afaik it has worked perfectly since then until last week. I think it is around 23 years old but it would be a shame to replace it because of a £20 part.

 

[Agile]

I have never seen a Sine 18 with a fan!

Maybe it needs a £20 part but it also needs an engineer to diagnose and repair which will be closer to £100.

Tony

 

[compheat]

I have never seen a Sine 18 with a fan!

Maybe it needs a £20 part but it also needs an engineer to diagnose and repair which will be closer to £100.

Tony

Like Tony as said Sine 18 is balanced flue only so it must be 242

 

[Agile]

I doubt the OP could come up with a trig value by accident!

More likely it is a Sine 18 but it was not a fan!

 

[S700JCB]

Update. The installation manual left with the system was for the VCW-Sine 18 however old service invoices etc show the model as VCW-242. Apologies for the misinformation. My sister has found a local engineer who didn't turn on his heels when she mentioned it was a Vaillant and he is going to have a look.

Thanks for the responses

 

[Agile]

BG will not take on any more Sine 18s and only do few repairs citing a lack of spare parts.

I think they might still do repairs on the 242s.

Tony

 

[spraggo]

Tell your engineer to suspect the air pressure switch. Part No 05-0518