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Oil Burner - OHMS When Running - Recycling

Hi Everyone,

I have a Carlin 702CRD oil burner with a Honeywell r7284 oil controller. When I turn off the boiler switch which completely cuts electricity to the controller to work on the burner then turn the burner switch back on the first time while running about a minute into the burner running it will stop and then recycle and once it recycles the burner will run fine. Is this normal? I've been sporadically checking on it since and it hasn't happened only when I turn off the power and then turn it back on during that first run time.

Also, after I had a mechanic come to work on it when it kept on locking out I notice when the burner is up and running the OHMS is displaying between 135-140 while before he worked on it it was around 350 or so. Is 135-140 OHM normal and okay? Should I be worried?


  • Dave Carpentier
    Dave Carpentier Member Posts: 579
    Ohms might be referring to the CAD cell, the part that watches the flame.
    My Beckett manual says that normal ohms is 0 - 1600.
    Higher than 1600, replace cad cell.
    30+ yrs in telecom outside plant.
    Currently in building maintenance.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    edited November 2022
    Higher than 1600, figure out why, not replace cad cell. Some burner/primary controls combinations run at higher ohms.
    135-140 ohms is ridiculously low and tells me the burner is not properly adjusted, which may be contributing to the nuisance lockouts.