oil burner - very smokey

[funcrusher]

Do oil pumps wear with age and produce lower pressure in the oil delivery to the burner nozzle? We live in a remote place. Our oil-fired boiler has turned very smokey recently. I've given it a thorough service (thoroughly cleaned boiler interior, cleaned all filters, new same spec nozzle, replaced suspect gaskets, replaced dodgy solenoid, bled the fuel line etc), but the smoking is getting worse. I've tried adjusting the oil pressure on the oil pump (DELTA) and air supply - no cure; smoking increases if the pressure is reduced. I'm wondering if the pump (over 10 years old) is worn and its delivery pressure has fallen so the fuel is not atomising properly.

 

[Bartdude]

Quite possible,you need an oil pressure gauge to check.

High smoke is caused by an imbalance in the air oil ratio. The boiler needs it's combustion settings checked,a job which requires specialist test equipment,and that means getting an OFTEC engineer in.

It's not a DIY job I'm afraid.

 

[funcrusher]

Sounds like the oil pump then. I live in a remote part of Ireland, but fortunately being a retired engineer can look after most things. I phoned a couple of 'service engineers' in the region - neither was prepared to even come and inspect. One said a new burner would be essential, the other said he was sure a complete new boiler would be the best option! Hard to believe, but absolutely true ! I guess they have no idea how to solve such problems and all these guys do is scrap and replace, or simply clean filters and flues for unsuspecting consumers

 

[kimbo]

You could just buy an oil pressure gauge to get oil pressure ok and see if that is ok but if you have already messed about with the settings you may have a problem. As bartdude says you need an often engineer to set it up. There must be someone out there who will come out.

 

[Bartdude]

What boiler do you have? I'd be very surprised if it couldn't be fixed,the parts on a pressure jet burner are all replaceable,it's just a matter of finding the culprit.

An oil pressure gauge will prove if the pump is faulty,and it's needed to set the pressure on a new one too.

 

[funcrusher]

Thanks both of you. You are confirming my thoughts - air/fuel ratio, buy a pressure gauge, probably the pump. I've tried adjusting air/fuel etc, smoking worse, carefully returned to original settings.

I imagine the pressure is too low to atomise the fuel fully, so that means partly a dribble. I tried switching on with igniter disconnected to check this, but as I suspected there is some interlock in the controls which keeps the solenoid shut off if the igniter is disconnected - so impossible to view.

Its a Thermomec boiler with a Delta pump (a gear type of course) and Landis and Gyr control unit, Danfos nozzle. Its been very reliable for many years, and fires up every time.

My area of doubt is in how pumps failure: is it gradual wear and loss of pressure rather than total failure?

Parts are certainly available in the Uk from Anglo-Nordic so no problem there - though irish service 'engineers' insist that lack of spares means inbstalling a new burner or complete boiler. I guess that is their lazy but expensive solution: get a puncture and tell the customer you'll sell him a new car!

 

[Bartdude]

Have a look at this,explains oil pumps very well.

heating.danfoss.com/PCMPDF/DKBGPG010A702.pdf

You'll have to copy and paste it

 

[WHPES]

Yes pumps can wear and bypass oil, resulting in smoking and / or vibrating flame. Most pumps have equivalent replacements. Needs to be the correct fitting, capacity, speed and rotational direction.

You should not be messing about with the settings unless you are qualified and have the correct equipment. It is impossible to set up properly without a flue gas analyser as well as a pressure gauge. Get a registered technician to sort it for you.

 

[funcrusher]

Thanks WHPES. Well understood.

 

[Dotty]

Whereabouts in Ireland?

 

[funcrusher]

about 400 miles south of Portadown!