vokera compact 25 he boiler fault-please help.

[freecall]

We have a vokera 25he around 4 years old with a fault which is driving me nuts!! the boiler keep locking out showing a solid red light.if you reset,it fires up ok then runs for a few minutes and does the same.also locks out after drawing off hot water to solid red light.first boiler cycle seems ok,fires up then shuts down when return up to temp,lights all green,when it tries to re-ignite it will fire up,ignite then shut down after about 5 seconds with solid red light.removed and looped through room stat but behaves the same.gas pressure ok.so far an rgi has changed thermiser,spark electrode and ignition pcb,but no different.any suggestions as to the problem as i have now spent a few quid and are debating weather to just cut my loses and replace with new boiler.would really appreciate any advise,many thanks


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[Mbear]

Hw flow switch may be sticking on, next time it happens remove one of the flow switch wires and see what it does. Ive had this a few times recently

 

[freecall]

many thanks for that,will give that one a go.is locking out though when on heating only seem to go through first boiler cycle,shuts down when return up to temp.when i comes to fire up when calling for heat,it will fire for around 5 seconds then lock out with solid red light.

 

[Mbear]

Ah right, u might have choked flow/return flexi hoses from h/e to l/h manifold. The fact it doesn't Do it on hw points towards circulation issues. Either that or faulty pump. I'd clear the hoses 1st of all, no parts to pay for that way.

 

[freecall]

thanks for that imfo,will give that a go later today ,pump seems to be operating ok as downstairs rads red hot when working.would addind some x400 for a few days help with shifting any rebris from the boiler.have access to powerflusher,is that work a shot do you think if i find and blockages in pipes.will report back later with results.once again many thanks for your advise

 

[Mbear]

Scratch that actually mate, I'm thinking about the SE compact. I'm sure the HE doesn't have flexi pipes. Sorry

 

[freecall]

thank again for your reply.just about to drop some x800 into system,guess i cant do any harm.think i,ll be looking at cutting my loses and just getting a new combi and fitting it end of next week.cant blow any more cash on this one:knife:will leave cleaner in for a few days and then drain down and flush outand see if that helps at all.would have to do this anyway if i end up fitting a new one.im not the first to get this issue according to google but cant find a post with a solution anywhere.

 

[GQuigley67]

post your location and someone local may be able to offer you a quote on installing a new boiler

 

[fixter1]

think solid red led is primary ntc has that been checked ????

 

[freecall]

think solid red led is primary ntc has that been checked ????

yes m8,he changed that first off,this boiler is doing my head in:death:.would you think a blockage somewhere in the boiler is a possible cause ?? have added some x800 this afternoon to the system,would need to clean system anyways if we end up installing a new boiler:yesnod:

 

[fixter1]

Could be a circulation problem try checking flow return temp