Rheem Tankless Water Heater Code 11 (No Ignition)

Discussion in 'Water Heaters and Softeners' started by sheltonfilms, Jul 13, 2017.

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  1. Jul 13, 2017 #1

    sheltonfilms

    sheltonfilms

    sheltonfilms

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    Water heater model: RTG-95DVLN (natural gas) 2014 build date

    So had this heater for 2 1/2 years and just the other day I got code 11. No issues up until this point.

    Thinks I have checked:

    Igniter sparks during startup.
    All solenoids are getting power and show correct resistances according to service manual.
    Removed and cleaned burner unit and manifold with compressed air.
    Check concentric vent for obstructions by looking into it from outside (comes out top of unit into immediate 90 out of wall unit is mounted on, 1.5' run).
    When blower comes on there is good suction on outer pipe and good flow coming out middle pipe.

    Now on to gas. I don't have a manometer but I made a quick and dirty one using clear tube and a ruler. There is a port on the gas inlet port. I zeroed out my makeshift manometer and turned the gas on and got 10" w.c. (spec is 7-11" for my unit). When I turn the unit on the pressure drops immediately to zero when the gas solenoid valve opens.

    I have 3/4" iron pipe from meter (directly on other side of wall unit is attached) and it runs about 3 feet and splits to the rest of the house and the other split is to regulator for the tankless heater. From there it is only 2 feet of pipe to the unit.

    I can turn on all 5 burners on my gas range (55,000 btus total) and it is fine. My tankless is 200,000 btus on full blast.

    Another note. I can smell gas when I'm in front of the exhaust vent but it seems it is more prevalent on the first startup. It doesn't smell strong until I let the unit sit and try to start it up again.

    Bad regulator for the water heater?
     
  2. Jul 13, 2017 #2

    havasu

    havasu

    havasu

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    This may help?

    [ame]https://www.youtube.com/watch?v=QsmIyYexRzM[/ame]
     
  3. Jul 14, 2017 #3

    sheltonfilms

    sheltonfilms

    sheltonfilms

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    Thanks for the video but I already cleaned the burner.

    Actually solved it today:

    Was looking at the regulator that was for the tankless unit that was installed outside. All the main diagrams didn't have the brass "bolt" seen in the picture below that I have. Well I found out it's a vent limiter and its for indoor installations only. It is so that if the diaphram ruptures it doesn't release gas into the house at a rate greater than ANSI standards. The reason it is not rated for outdoors is #1 it isn't designed to handle corrosion, #2 regulators placed outdoors don't require them.

    Sure enough after unscrewing it the unit fired up fine. Crazy how something so mall can kill a 200k btu appliance. The vent limiter was full of sediment and corrosion and the ballvalve was stuck inside.

    Called my builder (even though I was out of warranty) and pretty much told him I want them to provide me with the vent protector piece that is suppose to go there instead of the vent limiter he agreed and told me to document everything so that he could pass this along to the contractor.

    Hope this helps someone.

    [​IMG]
     
  4. Jul 14, 2017 #4

    havasu

    havasu

    havasu

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    Excellent. Thank you for the follow up.
     

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