Vokera Excell 80 SP - hot water not firing - (London N4)

[rossyl]

Hi,

I've got a Vokera Excell 80SP, it's had a few faults over the years, from blocked venturis, to failed fans and pressure switches.

The latest problem is that the hot water is not firing. This is a problem that over the past couple of months has got progressively worse.

The tap nearest the boiler always fired the hot water.
In the bathroom (one floor below) the tap would fire the hot water after some time, but the shower sometimes wouldn't (simple mixer taps).
It's now got to the stage where nothing will fire the hot water.

I'm guessing its the diverter valve or the flow?

The central heating seems to be working fine.

Does anyone know a competent boiler engineer who knows these boilers well? I'm in London N4.

Thanks,
Ross

 

[APHSLTD]

Hi,

I've got a Vokera Excell 80SP, it's had a few faults over the years, from blocked venturis, to failed fans and pressure switches.

The latest problem is that the hot water is not firing. This is a problem that over the past couple of months has got progressively worse.

The tap nearest the boiler always fired the hot water.
In the bathroom (one floor below) the tap would fire the hot water after some time, but the shower sometimes wouldn't (simple mixer taps).
It's now got to the stage where nothing will fire the hot water.

I'm guessing its the diverter valve or the flow?

The central heating seems to be working fine.

Does anyone know a competent boiler engineer who knows these boilers well? I'm in London N4.

Thanks,
Ross

New diaphragm required by the sounds of it. Why not get in touch with the last engineer that repaired it?

 

[rossyl]

The plumber I've originally used is now on commercial projects and is busy for weeks. Nice bloke, completely honest, and very sorry about it.

Spoken to someone else. He thinks it's the heat exchanger, and his plan is to clean it.

That sound like the possible issue?

If you wouldn't mind explaining more about the diaphagm.

Thanks

 

[nickso]

forget him. it's odds on to be the diaphragm.

 

[fanboy]

The domestic diaphragm is sat inside the domestic manifold, it's a brass section that's held with 6 screws. It's 9/10 the likely issue for tap turned on and not activating the boiler. The chances are its slightly ripped round the seems or bellied, either way replacing it wood be a cheap and probable start.

To understand it via picture : http://vokera.co.uk/wp-content/uplo...p_installation_and_servicing_instructions.pdf

Page 35, labelled : domestic diaphragm.

Hope this helps thanks.

 

[Agile]

Thats the most likely cause but there are also failed switches, seized glands and blocked venturis.

Until its been inspected nobody knows!

Tony

 

[rossyl]

Here's an UPDATE:

Having called out two people - the central heating stopped working and the hot water randomly started working! Both heating engineers had differing opinions as to the fault, (one said diverter and small heat exchange, the other the PCB), I wasn't convinced by either of their abilities, so I turned to VOKERA. One of their guys came out and had a look at it.

He said it was the main heat exchanger at the top of the boiler. He said that this was very badly scaled up, and was stopping the central heating bobin from working correctly and was also the cause of the hot water intermittantly working. He said that the temperature of the boiler was as a result getting way too high, it hit 90C.

He needs to order to the part but isn't 100% sure if Vokera still stock this.

Fingers crossed eh!

 

[Agile]

I will be very surprised if the cause is the main heat exchanger. I take it that its is not whining.

But then I have not been there!

I hope this is a fixed price repair as thats a more expensive part.

If it really was that then I would chemically clean it in situ and probably charge about £180. But I can do all that on one visit.

Tony

 

[DP]

Tony I am surprised you have not offered to diagnose and fix this boiler for £85.00 standard charge. I thought N4 would be in your neck of the woods. Easy diaphragm change no hassel.

 

[Agile]

Danny, to include repair of the hydraulic unit the £84 diagnostic fee is increased to £106.

In this case several people have now been fiddling and altered the apparent fault symptoms and its not clear from whats been said exactly what is now the cause(s).

I would be very surprised if this Vokera engineer has correctly diagnosed the primary heat exchanger as the problem. But then he has been there and we have not.

It will be interesting to see what it really turns out to be.

Tony

 

[rossyl]

Danny, to include repair of the hydraulic unit the £84 diagnostic fee is increased to £106.

In this case several people have now been fiddling and altered the apparent fault symptoms and its not clear from whats been said exactly what is now the cause(s).

I would be very surprised if this Vokera engineer has correctly diagnosed the primary heat exchanger as the problem. But then he has been there and we have not.

It will be interesting to see what it really turns out to be.

Tony

Hi,

The new part (main heat exchanger) was ordered this morning.

The new part is arriving next week, so hopefully will be fitted shortly after - I'll be sure to update.

 

[rossyl]

So the main burner was replaced last week, along with a Vokera Service Kit (that includes heating and water diaphragms)

- The hot water (which was working intermittantly) now fires faster.
- The still CH DOES NOT work.

It turns out that the second guy who came to fix it snapped the flow valve - so hot water to the CH system is shut off. He didn't tell me about this. A new valve has been ordered, but I'm starting to get worried about my pipes as it's now getting very cold.

The second guy was recommended, which is the basis on which i called him over. But I guess you never know.

 

[DP]

Rossyl, did you not get Vokera to carry out the repair?

It turns out that the second guy who came to fix it snapped the flow valve

Easy done- valve are c*ap

 

[rossyl]

Rossyl, did you not get Vokera to carry out the repair?

It turns out that the second guy who came to fix it snapped the flow valve

Easy done- valve are c*ap

Hey Danny,

Fair enough - would've been nice if he'd of told me.

Yep - luckily I did get Vokera in to fix - I paid £200, which covers all faults up to £450 in parts. So both the main burner, service kit, and this valve are included.

If I'd of gone with British Gas, they only deal with one fault and faults directly associated with that fault. So the flow would've been a different fault to the diaphragm - or whatever the fault was.

Fingers crossed the part arrives soon and it's above freezing.

 

[rossyl]

All fixed.

The new flow vale has sorted the heating issue.

Here's what i think - the first two guys were rubbish. The first guy was too young to know how my boiler works, and too scared to touch. The second guy, didn't know the boiler well and had a fiddle where a fiddle wasn't needed - and ended up breaking the flow valve.

Both I took on recommendations.

The Vokera chap replaced the main burner, a full service kit and the flow valve.