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  • sunfire commercial stove/oven pilot wont light

    guest created 1 week, 2 days ago 4 Members · 9 Posts
  • guest

    Member
    February 11, 2018 at 12:00 am

    6 burner sunfire commercial stove, two oven, grill. oven pilot suddenly wont light

  • fixbear

    Member
    February 12, 2018 at 8:43 am

    I understand that you probably have a Garland range, but what model would be a big help as they used many different gas control systems..  Is it a standing pilot or intermittent?  Again, model number is all important here.

  • Duster

    Member
    October 10, 2019 at 4:27 am

    I have the same issue with a SUnfire SDG1 oven. I have replaced the thermocouple and flame sensor rod. When you turn on the oven, I get lots of spark but no gas at the pilot light for the flame sensor. It has been an intermittent problem for some time so I thought it was a weak spark and or flame sensor? Anything I should be checking?

  • fixbear

    Member
    October 10, 2019 at 8:57 am

    You have confused me.  The garland SDG’s don’t use a thermocouple. They use a intermittent spark system by Baso.   Here’s how it works.  The controler calls for heat and 24 volts is applied to the ignition module.  The module supplies 24 volts to the first coil by PV and a spark to the pilot.  Once the pilot lights the sensing rod  Conducts a DC current to the module thru the sense terminal and burner ground.  Once the module senses a DC curent it will power the second solenoid to open the main valve. 

    Now if the pilot is not lighting, either the valve is not opening or the orifice is plugged or dirty in the pilot.  If the pilot lights and goes out, You probably have a sensing circuit problem.  Usually the burner ground.  You can determine this with a good DVOM in series set to micro amps DC. It should read about 10 microamps.  Early modules had no retrys and a 5 sec delay. You should also check the connectors for the wiring to the valve to make sure they are tight both on the valves and control module.

  • olivero

    Member
    October 10, 2019 at 8:58 pm

    Duster, this is for you.

    Intermittent failure to light or stay light in my eyes can very likely be a gas valve problem.
    I have had multiple gas valves that would open sometimes, then not or open once, heat it up and then not reopen when it was time to keep it hot.
    So here’s what I would suggest. 
    Hook your manometer to the outlet port, see if the gas valve opens, hook your A meter to the wires going to the gas valve and measure the A draw, it’ll be less than 1 most likely. Then check your data sheet on the valve and see what it SHOULD be. If it’s far below the rated A draw, that means the unit is trying to open the gas valve but not managing to open it, in which case it could be an internal flaw in the gas valve.

    Then compare, that’s how I busted my kettles that wouldn’t heat, turned out to be fault gas valves from Honeywell, pulled my hair out until I found out about the A draw being different, that solved it.

  • fixbear

    Member
    October 11, 2019 at 8:21 am

    Then check your data sheet on the valve and see what it SHOULD be. If it’s far below the rated A draw, that means the unit is trying to open the gas valve but not managing to open it, in which case it could be an internal flaw in the gas valve.

    I think you have that reversed. The high draw should be pulling the armature in.  Holding should be less.  But remember to always check the voltage first. They vary together as well as with the load.

    • olivero

      Member
      October 11, 2019 at 8:44 am

      Fixbear,

      In my experiences, I would be looking at a gas valve going, why won’t it open? I see the 24V volts, stably there and it won’t open, so I replace it and it works. 

      Then I found out later you could do A draws, stumbled onto it by accident, figuring there had to be something different somewhere and I measured A draw.

      Here’s what I saw,

      Valve gets 24V, tries to open, it’s drawing 0.55 A when it should be pulling 0.7A, the moment it went below 0.55A it wouldn’t open, when it was above that, it would. 

      That’s what I saw with this particular application but many times with the same model of gas valve.

  • fixbear

    Member
    October 11, 2019 at 10:53 am

    You must have been working on Honeywell’s. The higher draw of amps should be when the armature is partially out.  If the armature get’s to far out the coils magnetic power can’t overcome the spring tension because it is beyond the flux field.  However, if the armature separates from the valve seal, the armature will come in and the amps drop,  But the valve may not flow.  That’s were your idea of a manometer on it comes in.  Rarely do you see that with a Baso.  And on quality ovens, the controls and solenoid valves are not in the combustion area. They also often have cooling fans to the electronic area.

    • olivero

      Member
      October 11, 2019 at 11:54 am

      Yes, it was Honeywell and I’ve seen it on multiple honeywell valves.

      good to know, Honeywell didn’t really have an explanation for their valves failing, they just warrantied them.

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