riello 40 black smoke

[Best]

is your fga due for calibration ? just a thought maybe ?

Sounds likely. I would have it compared with another analyser. Riello 40s even when worn don't give much bother. Their oil pumps when old, tend to only work at 7 bar, which is ok. I would guess faulty nozzles, as common enough, or air setting not enough which can take a month or two for boiler to get worse.

 

[brianc1]

thanks again best. cant see though how if you set the air up with a flue gas analyzer(even if its faulty) how it would burn cleanly and only get worse after a month or two. one of these boilers was actually done in january and only went black few weeks ago and i have done lots of other boilers since january with fga and had no prob with them. the two burners in question were made in 1991 so im thinking its the burners and not he analyzer.....

 

[Best]

thanks best. to be honest i got a smoke pump the same time as my analyzer but never use it.

I would def recommend you use a smoke pump solely, at first to set up burner. Obviously after you check pump pressure. Get the smoke spot from slightly coloured & then fine tune to white. Perhaps a tad more air, then use your analyser. Probably find readings good. I wouldn't set co2 above 11 % on a Riello 40 running with 0.5 - 0.6 nozzles.

 

[brianc1]

best, why not above 11%? high co2 is a sign of good combustion. for me to adjust settings down to reduce co2 i would be increasing co? and reducing efficiency?. what am i missing??????

 

[Best]

Obviously you want co2 as high as possible, but lower output burners often have less co2. Be careful with them, especially the older burners for some reason, like the Riello 40. Settings for them years ago, on local manufacturers spec, was 10.5 co2 for small boiler. That is correct, & although it can be a bit better, you will find sometimes smoke number above 0 a little. That is why I say go by smoke gun. Often better not to set too fine, & you will still have good readings. Use old spec of boilers, if you can get them, for settings, but you can only do your best & you want the boiler to be fairly clean running & not so close to running sooty.

 

[brianc1]

just wondering best, would u always use smoke pump even when your fga is working correctly????? to me thats like pumping a wheel up with a hand pump then checking it with a compressor... do you not fully trust the fga?? i would presume because of the technology involved the fga is more accurate and if it wasnt why bother buying an analyzer in the first place? maybe its an age thing as i started with an fga

 

[Best]

Think oftec book said that maximum theoretical co2 is 15% for oil burning fully, but not achievable as boiler would soot up.

 

[brianc1]

never read that to be honest best, done a servicing course and as far as i remember the higher the co2 the lower the co so what makes it soot up??? not questioning your knowledge, just trying to increase mine

 

[Best]

No. Analysers are great, & you can get print outs etc. A smoke pump is a dead cert way of testing the " smoke " from the gases. To be totally honest, after you set the oil pressure on most burners with fixed nose cone set up, how many would you do anything more with, other than set the air intake? Most burners are spot on after smoke pump is used properly, & analyser will prove it. Smoke pump can often be used just 2 or 3 times at most when you are used to certain burners probable air setting, so can be very quick.

 

[Best]

never read that to be honest best, done a servicing course and as far as i remember the higher the co2 the lower the co so what makes it soot up??? not questioning your knowledge, just trying to increase mine

I am always trying to learn bits myself! I think it's like this :- an oil burner burning the oil as best as possible creates soot - sadly too much, so it's a compromise between less efficiency but cleaner burning & more eff but impossible sooting ( which even a small amount reduces eff anyhow ). If you put the air setting far to high, you often have a spotless boiler but the fumes was half burnt oil.( co2 very low).