Smoky oil burner

[Rewired]

I have a couple of quick questions regarding an oil burner I had the "joy" of looking at today...

Turns out my boss asked me to "look over" everything at his rental house next door to his, including the heating.... (forced H/W).. ancient cast iron convectors..
Anyway I started the boiler,( first firing after being off all summer). It fired fine but I noticed a LOT of blue smoke issuing from the chimney, I shut it off, cleaned the air vents and looked at the blower inside the burner for excessive dirt but it was all clean... I re-started the boiler and marked where all the air shutters were set and proceded to open them up to see if that would make a change but it did not. Lots of blue smoke was still coming out of the chimney, even whith everything wide open.. I gave up and set the shutters where they were originally and let the boiler run.. after about 45 mins I noticed the blue smoke did taper off quite a bit but there was still some visable... My question is ( just for my own curiousity's sake), What would cause that kind of condition? A bunged up nozzle or something in the combustion chamber of the boiler thats not allowing the flame to burn correct???

Also, another question regarding the aquastat settings.... its now set so the circulator pump comes on at roughly 135*F, turns off at 120*F, and the burner turns off when the boiler temp hits about 185*F and kicks back on at about 170*F... Do those temps seem about right?? Just wondering...


A.D

[imeduc]

Id say you can have a lot of ifs ifs ifs here for sure. First you should have put new oil filter in ,new nozzle ,reset and gap electrodes. For sure then start from there. That first ---lots of smoke can be that there was a oil build up inside the chamber. A burner should run for a while them set the air on it with a CO2 meter.
The burner can burn wrong from the nozzle bad ,the cone burned out as you said the chamber screwed up just lots of things.
Now the temp on the boiler most of the time we set them for 180o off and 160o on. For the pumps I dont get it what you have there. Most of the time the tstat is what turns the pumps on and off for when the home need heat. you sure the water is on and the auto fill is working right . For one floor you should have about 15PSI and make sure all the air is out of all the baseboard heaters.

Hope it helps ED

My mistakes dont define me they inform me.

[Rewired]

Hey ED Thank you for all the information!
I was just curious to what all was going on in that boiler as I am only an electrical apprentice but I do take interest in finding out WHAT or WHY or HOW something is supposed to work or shouldn't work depending on what the case may be.
In this case the Boss is going to have someone come in and give the burner a good going over, and I did let the boss know to eventually let the service guty know about the smoke problem... Thank you again!

As for what "I have there" for the pump setting... there is a "dual" aquastat mounted on the boiler, one of the aquastats is of course the high limit for the burner, the other is the control for the pump... In this setup I found: the thermostat turns on the burner, when the boiler is hot enough it starts the pump ( but then shuts off because the boiler temperature drops off with the inrush of cooler water) this goes on for a bit untill the whole system is hot... Circ pump stays running, burner stays running, High limit for the burner may shut the burner off if need be... when the thermostat is satisfied, the burner is shut down and the circulator pump runs until the boiler cools to about 120* and then stands by waiting for the next call for heat..... Doesn't really sound correct does it?

I did bleed all the air out of the convectors ( ya, very bizarre, they are old cast iron convectors built into the walls and covered with decorative wooden lattice).
Bleeding them helped a lot, as now ALL of them are producing heat...

I do have one other question though if I could trouble you regarding boiler pressures...
It is a two storey house that this system is installed in, boiler in the basement. The boiler gauge stationary pointer is set at 30 psi.. When the boiler is cold it shows 20-25 PSI... when it was hot, it was somewhere around 35-40 PSI... The expansion tank was drained, that was one of the first things I did actually while the system was cold, it was completely waterlogged..

No water came out of the relief when the boiler was running about 40 PSI BUT I did jiggle the handle on it and that was enough to pop it open and vent out some water.

As for the auto fill on the water line, I am sure its working correct. After I drained the expansion tank, I re-opened the valve between the tank and the boiler, there was an inrush of water into the tank and the fill valve started hissing until the pressure was back up in the system...

My question is: Does this sound normal? it almost sounds ( to me anyway) that either the expansion tank is too small or the auto fill valve is set a bit too high pressure wise...
If you can help me out again that would be great!!

Thank you again!

A.D

[imeduc]

Not there its hard to say. First the tstat should turn the pumps on and off not the burner. The boiler should be controled right there. The burner on at 160o and off at 180o. This is all so you have hot water for when the tstat need heat and turns the pumps on. not keep on pumping hot water up there when its already hot
40 psi on the boiler Id run not walk from it. This is not right. That pop off should go off at 30psi. New auto fills are set at 15lb.
You only need what psi it takes to make water come out of the top bleeder. Most one floor homes thats at 15 psi.Two floors at about 18 psi.

Hope this helps ED

My mistakes dont define me they inform me.

[Rewired]

Hey!
Thanks again for the information...
I will let the boss know that there is a potental problem and that he should have it looked at.. Not that vhe will though but at least I warned him!

A.D