Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

What would cause a locked out condition on gas fired oil boiler?

Jells
Jells Member Posts: 576
Before the season I skimmed and drained the boiler, cleaned the sight glass, and pulled and cleaned the LWC, making sure the autofill was working after. A few days ago I was in the property and the heat was on, then today a tenant said it was off, and sure enough, the red 'locked out' LED was on. The water was a bit low, below the line but not by much. Would that give a lockout? I reset, ran in some water, but there was no heat call so I jumped the terminals just to make sure it would fire. No problem. So any ideas why?


Comments

  • Jamie Hall
    Jamie Hall Member Posts: 24,467
    Gas fired oil boiler? Sure looks oil fired to me... but no matter, if the water is low, the system should lock out and stay that way until the water level is brought up. Your particular control may be set up so that if the system tries to fire but discovers that the water is still low and shuts down the burner control will lock out.

    Which is a very good thing.

    Why was the water low? Better find out and fix it...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Jells
    Jells Member Posts: 576

    Gas fired oil boiler? Sure looks oil fired to me... but no matter, if the water is low, the system should lock out and stay that way until the water level is brought up. Your particular control may be set up so that if the system tries to fire but discovers that the water is still low and shuts down the burner control will lock out.

    Which is a very good thing.

    Why was the water low? Better find out and fix it...

    It's gas, the guy that installed it liked this setup, and in 2012 it wasn't clear that oil would never make a comeback to be competitive with gas. Pretty clear now.

    Can you explain to me how the LWC both triggers the fill valve and the lockout? Does it lock out till it senses a fill? What would be the best way to test, just drain till the lockout light or the fill valve trigger?
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,240
    @Jells

    If you had to reset the burner control then you have a burner problem not a low water cutoff problem
  • Steamhead
    Steamhead Member Posts: 17,307
    That's a Smith 8 series boiler with Carlin EZ-Gas burner- they sold it as the G-8 series for some time. We installed a bunch of them too. Then they stopped making that version, and are now selling re-branded Peerless boilers.

    If you keep getting mystery lockouts, the primary control might be going bad. Carlin came out with a new version several years ago, which is more durable and includes some diagnostic features.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Jells
    Jells Member Posts: 576

    @Jells

    If you had to reset the burner control then you have a burner problem not a low water cutoff problem

    This is the part I'm trying to understand, what's the relationship? Is the LWC capable if triggering the lockout or does it simply depower the whole boiler to protect it?

    I've given my tenant some info on how to recognize the lockout, I guess we'll see if it's chronic.
  • Steamhead
    Steamhead Member Posts: 17,307
    Jells said:

    ..... Is the LWC capable if triggering the lockout or does it simply depower the whole boiler to protect it?.........

    The LWCO does not cause the burner primary to lock out. It simply cuts power to the burner if the water level gets too low.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • HVACNUT
    HVACNUT Member Posts: 6,208
    Basically, if the burner gets power to fire, then every safety before it is ok.
    The fact (as mentioned) that the burner attempted to fire but didn't means the problem is burner related. Whether its ignition, gas pressure, flame sense, faulty primary, poor combustion, etc is just a guess without instruments. 
  • Jamie Hall
    Jamie Hall Member Posts: 24,467
    May I respectfully add... even though it's gas, I'd still be very cautious about the reset on the primary. True, you can't fill the firebox with oil with multiple pushes. Instead you can fill the house with gas...

    Not sure which is more interesting.

    Get someone in there to find the problem and fix it.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • BobC
    BobC Member Posts: 5,495
    I installed the same boiler with the Carlin EZgas back in 2013 and it's worked fine since. I agree it may be an iffy gas gun primary controller/igniter. Has the system had regular service including the flame rod in the gas gun? If that gets contaminated it can cause this kind of problem.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Jells
    Jells Member Posts: 576
    BobC said:

    I installed the same boiler with the Carlin EZgas back in 2013 and it's worked fine since. I agree it may be an iffy gas gun primary controller/igniter. Has the system had regular service including the flame rod in the gas gun? If that gets contaminated it can cause this kind of problem.

    Bob

    I had it serviced in midwinter earlier this year. I guess if it happens again I'll get him back in.