Vokera cutting out after 15 minutes

[Nikita Norman]

I have an old vokera combi and since last night, it's only working for around 15 minutes at a time.

It works normally in that time - no odd noises, all smooth, and the house heats up normally. But then it just stops. Red light, no flashing.

When I first had it installed, it needed a new siphon each winter for the first three years. Could this be the same thing? It's old (about 14 years) so I can't remember what it was doing back then to know if it is!

 

[CBW]

Stating which model Vokera usually helps

 

[muggles]

If you tell us what model you've got @vulcancontinental might be good enough to offer some advice

 

[jeff the gasman]

Old vokeras Venturi issue. Gas engineer required.

 

[vulcancontinental]

If there's a siphon makes me think it's a condensing boiler, has it been serviced properly. But yes, model would help.

 

[Nikita Norman]

Sorry, it's a Compact HE.

Yes, condensing boiler. I've just had a closer look and the water pressure was a little low so I've upped that a bit.

 

[CBW]

I've just had a closer look and the water pressure was a little low so I've upped that a bit.

Does it now work as expected?

 

[vulcancontinental]

If the water pressure is low ignition will stop for 15 minutes to allow the user time to top up. If no increase after 15 minutes, red light lockout. We'll see if that's it because firing should have stopped so not convinced yet.

 

[ianmcd]

it needed a new siphon each winter for the first three years

Why would it ever need a new syphon ? I have literally hundreds of these on my books and never changed a syphon on one, sounds like yours needs cleaning, it is literally a lump of plastic, why would you replace it ?

 

[vulcancontinental]

Why would it ever need a new syphon ? I have literally hundreds of these on my books and never changed a syphon on one, sounds like yours needs cleaning, it is literally a lump of plastic, why would you replace it ?

I'm wondering whether it has the condensate sensor linked to the pressure switch or the probe in the recuperator.

 

[ianmcd]

I'm wondering whether it has the condensate sensor linked to the pressure switch or the probe in the recuperator.

Yes it does mate, thats why I think the condensate is backing up and switching the boiler off then gradually draining away, boiler can then come back on, then repeat, dont know why but the condensate trap on them collects so much more than Full steamers, an absolute must that they are cleaned on anuall service, but as said have never replaced one yet OP has had 3 ?

 

[vulcancontinental]

With the HE Ian, some of the early ones had a screw into the recuperator to shut off if the outlet backed up rather than the link to the pressure switch, might be that, rarely is the recuperator cleaned.