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  • south bend commercial oven doesn’t stay on. Turns on and off. Tech changed the theigniter but didn’t fix it, and now he thinks the control brd??

    Posted by guest on March 23, 2018 at 12:00 am

    Southbend commercial oven, it turns on ( the orange LED at the front) and after 2 second you hear a click sound ( a relay on the board ) and the LED turns off. If it turns on the temperature doesn’t stay to the set temperature for more than 5 minutes. 

    izzygreen replied 5 years, 5 months ago 1 Member · 5 Replies
  • 5 Replies
  • ectofix

    Member
    March 23, 2018 at 10:13 pm

    Yet ANOTHER question about equipment without providing a model number.

     

    Can’t help you without a model number.

     

    Since 1898, Southbend Range has manufactured hundreds of models of equipment.  A good, accurate model number might lead us to a good, accurate service manual…which would help us help you.

    PartsTOWN lists nearly 600 service manuals on Southbend equipment.  Some of those are INDEED convection ovens.  However, I have no clue know how many that is, but I’m sure there are many. 

     

    Additionally, I’m not THERE.  Nobody HERE (hearing your plight through a computer screen with highly insufficient information) can be THERE.  Your technician IS.  So none of us can second-guess HIS diagnosis without being…THERE.

     

    I suggest you that go with what your technician says.  If he was wrong in his original diagnosis, then his company should make it right. 

     

    While some equipment problems can be attributed to just a single part failing, I’ve had more than my fair share of there being MORE than one problem.  It happens. 

    After all, OVENS are called upon to constantly maintain cooking temperatures for up to eighteen hours a day, for seven days a week.  Such demands a toll on the equipment.

  • fixbear

    Member
    March 24, 2018 at 11:14 am

    Interesting that you don’t trust your tech.  IF you had told us a model number,  we would have looked up a wiring diagram on the oven and thought back to our previous encounters with that or similar models..  We also would have studied the designers circuits to determine what would cause what you are seeing. Like we would know what your light is for and when it is normally on.  I suspect it is for thermostat call for heat.. Which means that IF it goes out, the burner will shut off. 

     

      Now on most ovens I have worked on, the heat call circuit (temp control)  is in series with the door switch and the centrifugal switch in the fan motor to lock out the burner module.  It also may have a timer circuit involved for cook time and switches to engage the timer , preheat, or cool down.  And they usually require a low voltage transformer.

     

       The other thing we could have done for you IF we had a model,   is to determine if the control board controls the light. and when.  And what controls the inputs to the control board.  What controls the burner has.  The type of burner, open, closed, pressure, multiple firing rates, monitoring system and safeties.

     

       You also stated that he “thinks” it’s the control board. Are you sure he didn’t say ignition module.  They are different in both cost and design.  Ignition module controls the spark, pilot, and gas valves, and flame sense. And is often either Fenwall, Johnson, or Honeywell.   Control board controls temp, time cooking, and sometimes fan speed. and are special built to each oven makers design. Tech’s do not normally Think it is something,  They use meters to determine the actual problem before replacing a part.  Before condemning you igniter he should have measured flame sensor current/burner ground.  As for the click you hear, one has to confirm whether it comes from the board burner relay or the gas valve solenoid..  The latter is normally the loudest.  Unless there is a contactor like on a electric oven.

  • ryantruck9

    Member
    March 27, 2018 at 12:17 pm

    I would guess it is an SLGS series convection oven from the sounds of the complaint and front panel lights

    probably says Silver Star or Marathon gold on the reddish operator panel?

     

    this uses a HSI and flame rod.

    I would assume the tech replaced both the HSI and flame rod?

    Orifice alignment, burner cleanliness and gas pressure are very important on this burner system. 

    It is likely to be the ignition module problem now.

    When your unit started to fail originally I’m sure it was tried many many times before calling in a technician

    that can put some strain on the module, especially if you still have the old style Ign. Mod

    I believe RAM was the manufacture. They have since gone to Fenwall which seems better than original

     

    you will have to remove the bottom panel to get your Model # and Serial #

  • izzygreen

    Member
    March 28, 2018 at 8:27 am

    Hate to go to the simple side of things……but has anyone checked the door switch to ensure it is aligned properly?

     

     

  • badbozo2315

    Member
    October 13, 2018 at 3:37 pm

    > you will have to remove the bottom panel to get your Model # and Serial #

     

    True. And while you are there with the cover off, start the unit up, look at the sequence of events. This will lead you to which side of things is not working correctly.

     

    Yes, it’s undoubtably a SLGS series as Ryantruck9 says.

     

    Dollars to doughnuts, the flame lights off on the right burner, but doesn’t cross over the left end burner where the flame sense rod is, or it’s burnt off, as they all do. If this scenario is correct, pull the burner, check the gap between each piece-o’-crap (whoops! Cost-effective I meant to say) sheet metal burner that lets the flame jump from burner-to-burner. Open it to credit card sized slot, clean flame rod, reassemble.

     

    And while I say flame rod, the later ones are actually a thicker rod, while the earlier style is a thinner wire.

     

    I always replaced both the carborundum igniter and the ignition module if either was bad.

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