Air inlet problem with Trianco Eurostar 110 STD balanced flu

[JUB1L]

My Trianco Eurostar 110 STD oil boiler is about 10 years old and has worked without problems all that time. It is fitted with a Stirling 50 burner and has a balanced flue which goes straight out through the wall behind it. Oil is supplied via a Tiger Loop.

Earlier this year it started locking out. Our original engineer has retired so an alternative engineer (recommended by a neighbour) was called. He allegedly did all the usual tests and reported that he could not locate the basic source of the problem. If the air inlet hose is removed from the balanced flue box, it runs reliably. He left it running without the hose until his next visit whereupon he started converting the boiler to a 'conventional flue type' by drilling a 110mm hole through the 20 inch barn wall. Even this extreme measure failed because if the air inlet hose is extended by a further 6 inches, the burner pulsates for a second or so and then locks out. We have been left with a hefty bill for the hole (not yet paid) and he seems to have given up trying further.

The inside of the boiler is relatively soot free, the exhaust gas looks clean. The air damper is set to 14. I have tried adjusting it between 19 and 12 but it does not make any difference to the locking-out point if any additional restriction is added to the air inlet hose.

The engineer is supposed to have checked the oil filters but I am wondering if he has done the job properly. The oil pipe length and suction height are within specs for the Tiger loop and nozzle but has not a lot of capacity in hand. Can anyone advise if the above symptoms are consistent with a restriction in the oil supply please.

 

[Terrywookfit]

Did he check the snorkel tube for Co2 when connected to the B/F terminal?

 

[JUB1L]

I assume he did but I was not there at the time. He assured me that he had checked everything

 

[Terrywookfit]

If he did, there will be a small hole pierced into the snorkel tube.
Your problem is most probably vitiated combustion air, or poor combustion. Both will cause this problem.

 

[JUB1L]

Thanks, I shall have a look but is it not likely to have been tested before at anytime over the last 10 years or so?

 

[Tipper]

If it runs reliably with the air tube disconnected and dies when reconnected it is pretty clear that it is an air inlet problem.

Perhaps the tube has laminated and this is partially blocking the air flow?

If it is now 'conventional flue', is there an extract fan or tumble drier in the same room? These can rob the combustion air from the burner.

 

[JUB1L]

Thanks Tipper, The air tube is clear, no extractor fans or other devices to cause problems. Just laying the end of the inlet tube inside a short length of wider bore tube is enough to cause the lock-out.

 

[wilhelm]

I would change oil pump. errrr after checking the ebi transformer aint got a bump in it.

and if the fekkin oil pump dont cure it I put the old one back on etc

 

[lozinthevilla]

My Trianco Eurostar 110 STD oil boiler is about 10 years old and has worked without problems all that time. It is fitted with a Stirling 50 burner and has a balanced flue which goes straight out through the wall behind it. Oil is supplied via a Tiger Loop.

Earlier this year it started locking out.

Hello JUB1L

Did you get a successful resolution to you problem with the boiler?

I have the exact same model AND problem...

My engineer has told me to cut back bushes and trees around the flue. I have done this but its still locking out.

He also has taken the inlet pipe off too. But our boiler still locks out.

If you have an update, I'd love to hear it!

Thanks in advance...

loz

 

[JUB1L]

Hi lozinthevilla,

It must have been leakage between the inlet and outlet within the balanced flue itself. It has worked without problems since a separate air inlet to the outside was installed. Still do not understand why extending the inlet a little within the room caused lock-out but did not when extended through the wall though! Hope this helps.

 

[Boilerman2]

The flue seals on B/F Eurostars is a very common fault, the joints are taped and the tape dries out with years of heat and falls off causing recirculation of flue gasses, it only takes about an Hour to strip out the inner flue duct and re-seal it which enables the snorkel tube to be reconnected and the boiler restorted to "Room Sealed",

The diffrence between men & boys I suppose, but a good service engineer realises he can't pick & choose and has to get down & dirty sometimes I would find yourself another boiler engineer

 

[lozinthevilla]

Hey JU1L and Boilerman2,

Many thanks for the replies. I have phoned the engineer to come out tomorrow and shall share this with him.

Having already changed something with the ignition, hopefully this forum may give him some leads.

Many thanks again and I shall keep you posted!

loz

 

[tonyt48]

I also have the same boiler with exactly the same problems and have paid £200 to have parts replaced so far. Can I replace the seals myself? Do I need access to the top of the boiler? It has a back entry balanced flue but there is a work unit just over the top of the boiler. Thanks for your help.

 

[gassafeengineer]

is it wall mounted?

 

[tonyt48]

Yes it is mounted to the outside wall. When i disconnect the air inlet hose and tape it up with Gaffa tape the boiler works all day. As soon as i connect the flexible hose the boiler will only fire up for 20 to 30 seconds max. Is it a question of replacing seals? or stripping the flue down and cleaning? Thanks for your help