Vaillant Ecotec Exclusive 838 advice please on problem

[MrB123]

I know this is a year old, but I have almost the identical problem, sitting here on Xmas day in front of an electric fire!
Did this ever get solved?
I fear an ever increasing bill and no resolution.
The main PCB seems to be part of the pump, is this right, they cost £300 plus Vat.
Manufactured in 2009.
Happy Xmas one and all

 

[GuessMan]

If you still have the plastic grey pump, it's time for a Vaillant fixed price repair, or instant cover as they call it. Both the pump and PCB should be changed. They are different parts but the pump damages the PCB.

F20 is overheat btw and means the pump seized mid operation.

 

[MrB123]

Thanks very much for the info. It had the original 2009 pump which has a grey cover. After the original f20 I restarted it and it worked for about a day, sounded fine to me, then stopped again. Restarted and got ' water deficiency' message. Another restart and ok for another day. Then does self test and sticks on NTC. T turned it off in the morning it was leaking from the robber hose so I turned off the cold feed and drained it.
All sounds bad 👎.

 

[hugo60]

"I have a 6 year old vaillant Ecotec Exclusive 838 that regularly shuts off. This has started since a month ago. When I turn the hot water on. There is a very loud whooshing noise like a kettle boiling dry and then the boiler shuts off. with S.54 -waiting time, water deficiency (but there is plenty of water in the system)."

Anyone experienced this problem and knows what the issue is and how to rectify the problem

 

[muggles]

Does it happen in CH mode as well?

 

[GuessMan]

Hi Hugo, it could be one of three, or possibly all three things.

The cheapest first, the rubber hoses will be blocking up. They do this every 6 years or so.
Second, do you have the Laing plastic pump? It is easy to see it is grey plastic and awful. If so the pump could be failing. Normally noisy.
Thirdly, if the answer to the pump is yes, they can take out the relay on the PCB and cause intermittent failures.

If you have the Grunfos pump, metal with black label, it's not usually the pump.

The second and third points make it better value to get Vaillant out on a fixed cost repair - the pump alone is over £300 and get them to change the hoses and PCB.

Ps start your own thread next time

 

[Agile]

But Hugo should not be opening the room sealing front cover of the boiler to look at the type of pump.

Its odd the original poster had what they described as this whooshing noise and none of the Vaillant engineers attending seemed able to identify the cause or to fix it for very long.

My advice would also be to get Vaillant in for a fixed price repair ( after checking that they do indeed give a full one year warranty on their repair ).

Its difficult to describe noises but these descriptions imply air in the boiler which is difficult to imagine based on the suggestions made by others here and what the Vaillant engineers did on the original boiler.

Tony

 

[Agile]

The 838 is 32KW not 38

It's obvious you know far more than I do, so don't think I can help further.

He is actually correct, Dan!

The maximum power on the 838 combi into the heating is 30.9 kW when well condensing.

Its only on DHW that it gives 38 kW.

The difference is probably caused by the pump not being powerful enough.

Tony

 

[hugo60]

Thanks all,
I did have an engineer attend, he has cleaned the rubber hoses and was no blockages.
I do have the grey plastic pump which is what I suspect as when after the last service (oct 2014), the pump would make a noise for a short time and the noise would stop.
The engineer has ordered the pump (0020028056) and pcb(20049194)
I will await the outcome and update you all

 

[Agile]

Is that Vaillant fixed price repair?

 

[hugo60]

No it is not, It is with the engineer i called from the internet

vaillantservice.co.uk

 

[Agile]

Do you know how much its going to cost you?

Tony

 

[hugo60]

£450,(pump & PCB) but i have to go with this, had i known about Vaillant fixed cost repair, i would have gone with Vaillant.

 

[Agile]

Plus his fee!

That's a pity as Beerlover did tell you about the fixed fee at 0952 on Tuesday!

He also mentioned it in this thread on the 26th December last year!

We do try!

Tony

 

[hugo60]

Pump: 0020028056 (new modified part number 0020131637)
PCB: 0020049194 replaced and boiler now working.

In future will go to Vaillant for "Fixed price repair", hope i don not have to go that path