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Bad Primary Control

Rookie_3 Member Posts: 244
I ran into a Carlin Interrupted ignition 15 sec. primary control that is locking out on flame failure at approx. 2-3 seconds rather than 15. On start up with FF disconnected it makes it to just under 15 secs..(no start with FF jumped) The primary itself is testing out OK it just seems worn on the flame failure end to the point of too quick. CAD eye and leads are good also. How much less than 3 seconds should I let it go before condemning it?

Any thoughts are welcome, Thanks...........ROOKIE


  • Big Ed
    Big Ed Member Posts: 1,117

    A Riello drops out in seven seconds. The control locks out ,so it's safe. I can see a problem with a quick safety unless a delayed oil valve is in use . The eye does not speed up the lockout , but It can cause one . Check eye by using a ohm meter.......
  • Rookie_3
    Rookie_3 Member Posts: 244

    The eye ohms are good, high in the dark and low seeing flame. I am a little worried that with such a quick lock out
    that even the slightest alteration in the flame will cause a lock out on flame failure within 2-3 seconds. As far as safety if it was 16 seconds on a 15 second primary I would have pulled it already.

  • Big Ed
    Big Ed Member Posts: 1,117

    The Carlin relay will fall on standby if it reads a flame out . It will only lock out on a start up..Like I mentioned before a Riello has a 7 second safety.If burn cycle causes a lock out the burner needs work.

    I shed no worry for a fast safety I will save it for a long one..
  • Bill Nye_2
    Bill Nye_2 Member Posts: 538

    It is supposed to do that, actually 8/10th of a second. The 15 seconds is a trial for ignition, after the ignitor drops out and flame is established pull the cad cell lead and it will drop out with in a second. If you put the lead back on and wait a minute it should recycle and try again for ignition. Any of this make sense to you? I know what I want to say, just have trouble typing it
  • Robert O'Connor_6
    Robert O'Connor_6 Member Posts: 299

    two scenarios

    15 second trial for ignition and prove flame.

    Flame failure shutdown with in a second or two.



  • Rookie_3
    Rookie_3 Member Posts: 244

    Makes perfect sense. This is how the Carlin primary works vs. the Riello or Honeywell correct? I believe I need a more consisitant system when checking the timing for safety.
    I check some on start up while bleeding the pump when there is an OSV and can't gravity bleed, others I'll pull and time. I was taught not to worry when they are worn and say a 45 sec. locks out at 40 secs. or lower. I just didn't know how low before they started to be a problem.
    I guess if 8/10ths of a second is OK there is no "too quick"

    Thanks again.........................ROOKIE
  • Firedragon_4
    Firedragon_4 Member Posts: 1,436
    8/10 of a second to

    verify flame is the norm for a cad-cell response time. Throughout the industry however, processors and relays react a little differently to that effect. There's more on this in our book on Primary Controls;
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