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why boiler doesn't start automatically?

oldutica Member Posts: 16
Thanks in advance to anyone who will help me diagnose the issue just recently started happening..

-- sometimes boiler stays off without firing back up even when there is demand for heat (with thermostat requesting heat). I have been pushing the "reset" button to get it firing back up...it works for about a day going on and off as normal, and then stays off...
Any idea what is at issue? where to begin? I don't know much about how the system works but can work with some direction.

Old utica boiler (oil fired water boiler) with a coil. water tank heated via the coil. there is Honeywell R4184 D 1027 (Intermittent Ignition Oil Primary) which has the reset button.
Also there is Model "AFG" Series Burner MP1192
Also Suntec A2VA-7116 ??

I paid a burner guy close to $200 to look at it but when he came it was working as normal and he didn't find anything related to this issue. I am trying to figure this out if I can than paying $135/hr to diagnose this sort of intermittent problem. It seem to happen often enough that there is definitely an issue.

Thank you to anyone who can help out! Cheers!


  • newagedawn
    newagedawn Member Posts: 586
    first, whens the last time you changed all the filters and nozzle? had a cleaning done? also sounds like a bad cad cell or primary control
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
  • oldutica
    oldutica Member Posts: 16
    Thanks for replying.
    boiler service /tuneup done less than 6 months ago -- in Oct '17 and oil filter was replaced again last week, just in case.

    Don't know any nozzle got changed. Which nozzle? The guy said may be the transformer or it might be sludge /clogged oil lines. The pressure on oil inlet was 9 and it went down to 7 with new filter.
    Can you elaborate on cad cell / primary control? how to go about it... thanks again.
  • oldutica
    oldutica Member Posts: 16
    just read a bit about cad cell..will do a resistance check to rule it out.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,132
    Stop pushing the button!
    If it doesn't fire you'll just keep dumping oil into the chamber, then you better hope it doesn't fire.
    Fixing oil burners requires skill, experience, and the proper tools to test. Then proper tools and skills to set up combustion.

    What's checking the resistance actually going to tell YOU?
    This statement is the sign of a non-professional:
    "...the guy said may be the transformer or it might be sludge /clogged oil lines..." All easily checked, so why the guessing?

    The pressure on oil inlet was 9 and it went down to 7 with new filter. That's not pressure it's vacuum, and it's still too high. Need to find out why. You're high vacuum is probably causing your lockout. Again, a pro will use tools to confirm this.
  • oldutica
    oldutica Member Posts: 16
    Thanks for replying SteveUSA. I know its best for a pro to diagnose it systematically and find what's causing it. I am not a pro and don't claim to know how the whole system works... Every pro visit is about $200 in labor, so hoping it gets fixed in one pro visit..

    Thanks for the advise to stop pushing the reset button !!!

    When the pro checked it last week, system worked ok and if I didn't tell him why he was there (this intermittent "not coming on" problem) he wouldn't know if there was any problem. I asked him to see if the oil filter is clogged or something. And then he checked the vacuum (9) and put in a new filter (afterwards vacuum 7)... yes he said should be lower, but didn't do anything about it. he said oil lines may have junk/sludge as a reason. What should the vacuum be at the oil line inlet?

    If I can, I just want to understand what might cause this intermittent problem. That's why I posted here. If it is not something easy to figure out or fix by myself, I would of course get someone to come do it. I can check voltage etc w/ multimeter that I have. What other tools might I need to diagnose this? I am ok to open and check stuff if I have some instructions.
  • Fred
    Fred Member Posts: 8,541
    You say this is a "water boiler" but does it produce steam or actually circulate hot water? If it is steam, check the pigtail (looped pipe that the Pressuretrol is mounted on). Those pigtails get clogged and prevent the Pressuretol from dropping the pressure back down to "Cut-in" pressure until enough pressure leaks past the clog to allow the burner to fire.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,132
    edited April 2018
    I would have him remove the filter element, blow back the oil line with a hand pump to eliminate if it's 'clogged', replace with new filter element. Properly bleed, and check to make sure the firomatic valve(s) are fully open, and there are no kinks in the fuel line, or anything that would restrict flow. Then pressure and vacuum checks on the fuel pump.

    If it's a gravity system, burner below the oil level in the tank, you should show 0 or 1 vacuum. If it's a lift job, oil burner above the level of the oil in the tank, should read about 1 for every foot of lift, about 1 for every 20' of run. So a heater 20 feet from the tank lifting 5' would read about 6--which is approaching the maximum amount of vacuum you want on the system.
    If the tank is in the ground outside, and you can't resolve this high vacuum, you may want to add an oil deaerator (Tiger Loop).

    Once it's confirmed that it's not the oil line, I would start checking components.
    Transformer, and motor. Checking voltages on all components.
    I then would bleed and fire up the burner, check the primary control and ohms, and the oil valve (if any) and ohms.
    Then a full combustion test.
  • oldutica
    oldutica Member Posts: 16
    Fred, thanks for your reply. We have baseboard heat which circulates hot water through pipes. It is an old Utica boiler model SFH5175WT.
  • oldutica
    oldutica Member Posts: 16
    SteveUSA..the tank is about 10-15 feet away at the same level...so oil level may be about 1-2 feet - so may be vacuum level of 2 - 3 should be normal, I guess. I think I should get new oil lines put in.
    EBEBRATT-Ed Member Posts: 13,440

    Your technician is very unprofessional. If your burner is going on lockout there is probably about 6 or 8 common things to check before you get into more difficult stuff.

    Your technician is charging you and should give you something for your money. He should (at the very least) be checking the basics even if he doesn't see anything wrong.

    Problems don't always jump out at you. You have to look for them.

    get a new technician
  • lchmb
    lchmb Member Posts: 2,997
    where are you located? 7" vacuum tells me you need some work done... Maybe someone here is located close and can help you the right way..
  • oldutica
    oldutica Member Posts: 16
    Yes I will call someone else next time. Thanks. We are in southern CT.
    First off I think oil lines need to be replaced (probably more than 25yrs old) — and then see if the problem still persists.
  • oldutica
    oldutica Member Posts: 16
    If I understand correctly, 7” vacuum can be caused by restricted lines?
    HVACNUT Member Posts: 5,025
    > @oldutica said:
    > If I understand correctly, 7” vacuum can be caused by restricted lines?

    Yes, but that doesn't necessarily mean they have to be replaced.
    You're stating oil lines, plural. Is it a 2 pipe system? Oil lines come off the top of the tank? Or one pipe oil line, singular, off the bottom of tank? How old is the tank? A Suntec A pump can usually handle 7" of vacuum, although it's not healthy. The process of elimination should be done by diagnosing the problem, not throwing parts at it until you hit the jackpot. There are plenty of guys on this site who serve S. Connecticut. I highly suggest you click on the link "Find a contractor in my area", and get it done right. It just might be oil related, or it might not.
    Baby needs new shoes. C'mon 7!
    Don't roll the dice on this.
  • oldutica
    oldutica Member Posts: 16
    HVACNUT, thanks for replying.

    Two oil lines from top of 275gal tank. One line goes to filter IN and the other line is connected from below where the burner is... may be a return line?

    The tank is new, put less than 2 years ago -- I was told by other techs afterwards that the guy who put the new tank has taken shortcuts. Also he put the oil from the old tank about 90-100 gal into the new tank. I asked him to filter the oil but he never did. He said he is experienced in this and knows how to not let the sludge go in and filtering the oil will take a long time. Oil lines were not replaced.

    I agree with you not to throw parts at the problem. I was told by the tech who was here last week that I should get the lines replaced. So that's also why I am leaning that way -- trying to check if they need unclogging (using hand pump etc.) will also cost labor. I was thinking it might be cost effective to replace lines given that there is a good possibility that they could be clogged.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,132
    I must state again to find the problem first, before replacing parts. Could be something simple, like a firomatic partially closed, or gunk on the inlet of your filter, or valve, or a ball of goo getting sucked into your supply line, stopping burner, then falling off. You re-start burner, then it does it again.

    I didn't realize it was a 2 pipe system.
    --Why are you relying on this statement--
    I was told by the tech who was here last week that I should get the lines replaced
    Is this the same tech that told you it was ok to use the old oil?

    Every new delivery you should put in an additive, if your fuel filter looks nasty when replaced, until all the crap is out of the tank. Shouldn't look like that with a new tank. Hopefully they didn't plug the bottom of the tank but put in a valve so you can drain water/sludge annually.

    With the oil lines coming out of the top of the tank, your tank is accumulating water, combined with the sludge the last guy put in there, to create more sludge, microbes and more problems.
    I'd also switch to one pipe (remove by-pass plug or ruin your pump), draw from the bottom, and pitch the tank towards the line, properly bleed and be done with it. (Tiger loop under protest). Tank>firomatic>General & Spin-on>OSV>firomatic at burner is the proper way. Now, combined with the additives, the crap will work its way into the filters, so you can get it out of the system.
    With 2 pipe you're constantly move something like 17g of oil when your burner runs, with the return line stirring up the tank. This shortens the life of your filters.
  • oldutica
    oldutica Member Posts: 16
    Thanks for writing all the info above to help me. I didn't know re: 2 pipes vs 1 pipe option and tiger loop etc. No I never called the tech who replaced the tank -- as he also did some other shortcuts and damage. It was a different tech who was here last week.

    I didn't know they could have put in a valve to remove sludge annually... Is it too late now? I have been adding 8oz of STR-2+ fuel oil conditioner before every fill up as instructed by the tech who serviced the boiler in October (a different tech.)

    Well I need to get someone in here to do a proper job looking at the whole system and correct any issues like the ones you are raising,

    I was planning on replacing the old water tank with an indirect by creating a new zone to its coil and shut off the coil in the boiler --there is a small water leak at the coil. I have to look to do it sooner and get all taken care of in one shot.

    Small water leak at the coil in the boiler -- could this cause the boiler intermittent "no start" issue? I didn't think this will cause it -- the coil leak had been in this condition for at least couple of years.