No announcement yet.

2021 22MLE Furnace not firing

  • Filter
  • Time
  • Show
Clear All
new posts

  • 2021 22MLE Furnace not firing

    This is our first season with this camper. We dry camped for a week, using a generator to top off the batteries once. The furnace ran fine. We then went on another trip and the furnace blower would turn on but not ignite. We were told by our dealer that the batteries were probably below 11.8 volts and the furnace would not ignite at that level. The voltage indicator in the rv never went below half. Since we were on the road we changed batteries (the other ones were about 3 years old) ourselves. We charged up the batteries and all seemed fine. We went on another trip and the furnace again would not fire if the batteries were even slightly below full. Furnace ignited when hooked to a generator or shoreline. Took it to the dealer, as it's under warranty, and they told us that we must have let the batteries get too low. I find it hard to believe that with the battery indicator showing 3/4 full that there would not be sufficient voltage to run the furnace. I didn't put a voltage meter on the furnace itself to see how much voltage it was getting, but the batteries never showed less than 12.3 volts. Any thoughts?

  • #2
    campermandan That is a strange one. I would start by getting a battery monitor with a shunt. I am a fan of the Victron gear, but there are other cheaper options. The factory gauge unfortunately will not tell you much, and it sounds like you dry camp a fair bit, I think it would be a useful investment. It will act like a gas gauge for your RV and actually count the amps going into or coming out of the battery to tell you how much charge you have.

    All that said, assuming your voltage measurements are correct I would be curious to know the voltage at the furnace. It obviously had enough to run the fan which is not insignificant. Normally when the blower runs but the furnace does not light I would look at either the sail switch or the gas valve. The sail switch is cheap enough to replace you might just want to try it. The gas valve, you should be able to check the voltage at its connection point and see 12v on it when it opens. You should also be able to smell gas. The sail switch is before the gas valve in the circuit though, so I would start there.
    Neil Citro
    2018 Reflection 28bh
    2019 F350 6.7L Long Bed Crew Cab


    • #3
      I would tend to believe that if it runs on shore power and also on generator power that there is either a battery issue or there is not enough voltage getting to the furnace when only on battery power. You have to remember that a deep cycle battery will not run a furnace very long, even 2 deep cycle batteries. Also how much other things are running on the battery power before trying to use the furnace?

      Brian & Michelle
      2018 Reflection 29RS Oct.2017 build date, EMS-HW50C , Lippert Remote
      2015 Chevy 3500HD CC LB Duramax , Reese Elite 18K


      • #4
        Is the solenoid gas valve on the furnace working? Have someone set the thermostat to heat while you listen at the valve for it to click. Make sure the wires to the solenoid are well connected.

        The ignitor gap may not be correct to create the ignition spark.

        Like an engine, it needs air, gas, and spark.
        2021 Reflection 310RLS
        2020 F350 PS,CC,LB,SRW


        • #5
          To summarize what I understand is happening: runs on shore power and generator but not on battery power alone.

          1. Most likely, almost 100% certain this is not a furnace issue.

          2. Symptoms are pointing to a bad connection between the battery and the fuse panel. On battery power check voltage at the fuse panel, with and without the furnace running. Bad connections sometimes only show up under load.

          The battery and the converter are wired in parallel to the fuse box. The furnace is wired to the fuse box. So… if there is bad connection between the batteries and the fuse box, the furnace will see a lower voltage when on battery power alone.

          EDIT: since the furnace runs on shore power the issue is probably not the wiring between the fuse box and the furnace.
          Last edited by colan; 09-24-2021, 08:20 PM.
          Colan Arnold
          2016 Momentum 397TH
          Full time since 2016


          • #6
            campermandan Excuse me for being tardy to your party.

            Welcome to the Family and the forum!
            Jerry and Kelly Powell, with Halo, Nash, Reid, and the baby kitty Cleo.
            Pilot (Zebulon), NC
            2020 Solitude 390RK-R


            • #7
              Hi all,
              The dealer was leaning hard towards a battery issue, but after taking a deeper dive into it they found the sail switch was defective. All good now. Thanks for the suggestions tho!


              • #8
                Glad you were able to resolve it.
                Jerry and Kelly Powell, with Halo, Nash, Reid, and the baby kitty Cleo.
                Pilot (Zebulon), NC
                2020 Solitude 390RK-R