Vokera Linea 28 - Fires Up at Night

[Marc Edwards]

Hi,

I have a Vokera Linea 28 which fires up at night between 2am and 5pm.
This happens when the boiler is in either in HW or CH/HW mode.

I have had a corgi registered engineer out who turned off the pre-heat under instruction from the Vokera Tech dept.

However the noise keeps occurring since the pre heat has been turned off. No taps are being turned on when the noise is made. Also, the boiler does not make the noise when the wall thermostat is turned down to its minimum temp.

There is no timer clock on the boiler either, but I am assuming this shouldn't mater in the case of the CH not being turned on i.e. no clock needed - I could be wrong on this though.

Does anyone have any ideas on how to stop this problem?

Thanks in advance,

Marc

 

[Chilly67]

sounds as though it could be a problem with your frost sat (if fitted) when the temp drops below a pre-set temp then the boiler will fire up to protect pipework and boiler etc, only a suggestion

 

[Marc Edwards]

Thanks chilly67, not too sure what a 'frost sat' is - how would I know if one is fitted? Is a 'frost sat' something that a corgi reg'd engineer would know about or is that Vokera specific knowledge?

 

[Alfredo]

There is also a pump exercise programme on the Vokeras which spins the pump to stop it sticking, but I'm not sure how often..even though I've got a Vokera Linea upstairs!

If its not the HW preheat I'm a bit stuck. Its too regular to be a fault..must be some 'secret' feature none of us understand. I think mine does the same come to think of it, but I only notice on those occasional sleep disturbing visits to the bathroom

If it does not do it when the room stat is off..it may be a dodgy room stat. Stick a basic Honeywell room stat on or treat yourself to a nice little programmable stat, then you don't need a time clock. I have a Danfos TP5 programmable stat..which is nought special, but does a brilliant job.

Did you really mean 2am to 5 pm?..thats a hell of a long run

Alfredo

 

[ChrisR]

Pump exercise wouldn't make it fire up, are you sure it fires?

Are you sure the water preheat really is off?

 

[Trance Nation]

Odd one that.

Once i did see a fault where the primary sensor was gubbed and it fired up itself thinking it was cold, although this happened maybe once an hr rather than the specific times u have mentioned.

I assume ur corgi has succesfully turned off the preheat function. It's only a little jumper on the pcb on that model im sure. A 2 min job sir !

More than likely has to be a clock fault if its firing up and staying on for that time, or as mentioned already it may not be firing up and only coming on at around the same times each night as a pump checking excercise.

Maybe when u come back in from the pub over the weekend u can check if it definetly does fire up.

 

[Agile]

Most pump exercise times are calculated as about 27 hours from the last time it operated. Daily use of the boiler would inhibit that function.

Perhaps more likely to be a frost protection malfunction. Is the boiler fitted in a cold place like a kitchen?

My solution would be to check the NTCs carefuly at the same temperature against the correct values.

Tony

 

[Marc Edwards]

All,

Many thanks for all your responses. Alfredo, I did mean 2am to 5am - fair play for pointing it out.

The guy who came to fix it (corgi registered) did turn the pre heat off by tweaking the jumpers on the pcb (I think that's what it's called). It only took him a couple of minutes so it sounded like he was doing the right thing but it didn't stop the issue.

I've ended up contacting a company who services the North London area. I'll pass on everyones thoughts to him and if it the issue is resolved I'll feed back the solution to the forum.

Thanks,

Marc

 

[Agile]

I really do not like a customer telling me what his friends in the pub have told him they think is wrong.

As someone who repairs boilers daily I expect to have a better idea of what the problem is myself.

I once had quite an argument with a lady who asked me to come and replace the pump in her boiler because another repairer had said that was the faulty part. I knew it was not at fault from the symptoms quoted.

She finally reluctantly agreed that I could diagnose the fault myself. She apologized later when I showed her that her PCB had failed.

Tony

 

[Marc Edwards]

Thanks Tony.

 

[niggle]

The Linea 28 will activate every 19 hours to stop the pump and diverter valve sticking. This behaviour is independent of the DHW preheat.

See "Installation and Servicing Instructions", page 32.