smelly oil fumes

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I am going round in circles a bit and its getting really frustrating trying to find what I have wrong! I have a 25 year old Thorn Panda 120 oil boiler and put a new EGO 500? burner on last year but this year having thought it was set up properly the fumes are smelling. I got a 12 % reading and virtually no smoke with a psi of 150 on a .75 nozzel so it is working at the bottom end of its range for a 35kw boiler. Thanks to oilman I fixed the bearings on the motor of the old burner and have it as a back up so may have to change back to that for the moment. Thoughts and suggestions would be much appreciated.
 
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150psi? is it gas oil?
I'd be looking at around 120psi on kero.
try getting the 12% down to 10% or 11% and see how she runs.
 
I ended up at 150 as at lower pressures it was worse and I wondered if I was having at attomisation problem accepteing you would not normally exceed 140 psi with 28 second oil. The manual says with this burner you should be able to get down to 11% so I assumed 12% was quite good as no doubt they claim about as good as it can get. I have always felt its a lack of air intake but I can't fathom why, I could just try without the foam around the inside of the air intake just to see the effect. This is clearly meant to be left in place.
 
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Thanks for that. I THINK I have made some good progress this morning. I clearly had it very wrong on the 1st Nov when I set the 150 psi, I do have an air heat pump as well (primary source) so the oil boiler was not working very hard at that stage (kicks in 20 min after AHP if it needs help) and despite having a very low smoke reading on the smoke pump, this morning the eye glass was lightly black all over. I have set 120 psi and part of the problem is my lack of knowledge and a somewhat poor manual for the testo 325S which I bought as there is no explanation of what the readings really mean.

I shot up to 15% on the lower 120 psi pressure (understandably) but now having restricted a small part of the air intake on the EOGB X500-2 burner working right at the bottom of its opperating range with tape as the o2 intake did not seem to have a range in the right area I now have o2 at 10.5% EA which I believe is "excess air"? of 99.9 apparently the display has an "f" after that but that does not come on whatever it is? CO2 of 7.8 (what is a really good reading for 28 sec oil?) when the OAT Outside Air Temp was 4.6 oC. Part of the problem is the manual nor easily found on the internet is what ideal 28 sec oil readings should be, obviously page 1 on the training courses and so basic you should alreday know! I don't!!

I appreciate tuning is a compromise and affected by OAT on the day, colder being more dense (turbocharged!) but am I guessing right on a warmer day I am going to end up running a bit too rich again?
 
I was going to ask whether it was sooty inside - you might want to give it a clean out now.
I like to set my burners up at 10-11% CO2, O2 should be around 6-7% with 0 smoke, so take off a bit more air.
 
Clearly not perfect yet. I have just done a smoke pump test and that is indicating just over the one at the moment but well under the two. Will go out and try to match your figures with a bit less air.
 
Update! I now have O2 of 6.6% EA of 46.9 but I don't understanding this figure at all, CO2 of 10.6% and OAT of 5.8 oC but my smoke content has increased from low one to a two so clearly a long way from "no smoke" so what compromise of tuning do I now need to make?
 
What CO reading are you getting? It could be your nozzle is too small for a 120 boiler, I would have thought you would have been nearer to a 1.00 gallon nozzle or 1.10. Too low an oil throughput on a X500 burner will make the flame too cool, hence high CO and soot.
 
More good progress as no oil fume smell in the house this morning so just a case of not running at peak efficiency now as the EA Excess air is about 50% when I believe it should be nearer sub 20% so heat is being lost up the flue. Thanks to you it has led me to a website which puts all your figures into context with a graph etc, for the benefit of others at my low knowledge level who may read this the link is http://www.engineeringtoolbox.com/boiler-combustion-efficiency-d_271.html The CO2 reading was stated above at 10.6% and I think your comments may be spot on about the nozzel / burner.

The reason being, following more investigation is despite me asking for and ordering a EOGB x-400 burner I was sent a 500 and when I questioned it I was told that was fine as it was better to operate at the bottom of the range of the burner rather than the top and they only had the 500 in stock, this did seem strange to me as they cost a fair bit more. Further investigation shows they supplied me with a X-500-2 rather than even a x-500-1 that has an operating range of 28-50 kw and the -2 is 50-70 kw. This would explain why they air intake was all wrong as it was expecting a bigger nozzel and more fuel and more air. The manual indicates the main difference being the setup of the actual electrodes gap and positioning, so I should be able to improve this?

The burner came supplied with a 1.35 nozzel and the EOGB help desk said I needed a 1.0 nozzel for my Thorn/Panda 90/120 boiler with about a 35kw capacity or I would overload it at about 60kw and blow it up. I could not get that to run properly so put on an old .75 nozzel which at least got rid of the smoke on the smoke tester, then bought the flue gas analyser which confirmed all the other factors were way out!

I think my best move now is to change the nozzel back to the 1.0 and adjust the electrode settings etc and see what sort of readings that produces and hopefully reduce the smoke contents and the excess air reading?
 
You should be adjusting oil pressure to suit the desired output for a given nozzle size AND the air damper setting to get your CO2 where you want it. Doing one thing in isolation won't work.

Danfoss do a guide that sets out the nozzle size/heat output ratio, etc. Google it.

You should not need to adjust the electrodes at all assuming the burner lights up, except if there is way too much air flow which 'blows' the spark out!

Excess air is irrelevant on a domestic sized burner, as is efficiency. Just get the CO2 correct after selecting the right nozzle size and oil pressure..
 
Bearing in mind the boiler is 25+ years old it's unlikely to give you text book setting, you may need to be flexible with the old girl.
Take Tipper and Oilheads' advice re nozzle and pump output (120 psi is the figure I go with as rule of thumb and set the combustion from there). I would concentrate on getting the smoke 0-1 and as said earlier CO2 10-11%, 12% on the bigger beasts.

Have a look at the Bacharach site if you're interested in how it all works (with an American flavour).

Would it not have been more economical to get someone in to set it up? that's a fair bit you've laid out on the burner plus FGA (I still use a wet kit).
 
Thanks, point taken on money but I went down this route as ripped off by two professional registered firms in 3 years. It was running fine after the Guv of one firm set it up 5 years earlier and I was talked into a full service having reminded them untouched for 5 years with them to discover when the burner bearing went in old age a month later, the nozle had not even been changed and all the fire cement on the top to the flue was loose, missing and wobley so all they probably did was hoover out, the casing had not even been put back half decent (outside brick shelter) and this was 2 blokes for and hour and a half and not on a fixed price! They quoted £750 to supply and fit a new burner and £400 to fix the bearing (£10 thanks to Oilman) and on a 25 year old I could see it could easily spring a water leak next, so a good opportunity in semi retirement to learn!.... on what most would understandable say time it was changed. With the Air heat pump at 12kw and a DC100 control box and shut off valves for oil or water even with oil faliure it was not desperate with the lounge fire roaring while I sorted the burner when it was zero to 5 degrees outside, definetley cool and not cosey!... but OK. It is nice to understand these things ....and satisfying when completley solved, makes the grey matter work. Having said that I have no problem what so ever paying a professional who does a good job and is fair value but regrtable often hard to find in many walks of life.
 
The original that had the motor bearing failure after 25 years was the .75. I think I have an old .8 off it in the box somewhere. The X-500-2 came with 1.35 which was fine but too powerful for the casing and I could not get the 1.0 they recommended to work but that was early this year before I know what I know now! Presumably more fuel more power out is not necessarily less efficient as it runs for less time?
 

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