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GetGoing's avatar
GetGoing
Explorer
Feb 20, 2020

Replacing a WFCO 9855, Options?

When plugged into shore power, after a few hours the coach batteries were drained. Lots of YouTube articles learning about RV electric I am very confident that the converter is not working. This was installed in a 2007 Coachman Mirada and seems the same model is still available. Amazon posting said it was a 3 stage converter which I assume was referring to the stages of battery charging. I would value input from others as I research from other internet sources.
  • GetGoing wrote:
    When plugged into shore power, after a few hours the coach batteries were drained. Lots of YouTube articles learning about RV electric I am very confident that the converter is not working. This was installed in a 2007 Coachman Mirada and seems the same model is still available. Amazon posting said it was a 3 stage converter which I assume was referring to the stages of battery charging. I would value input from others as I research from other internet sources.


    No. The "three stages" are just three voltage levels of the charger. (14.4, 13.6, and 13.2) They call these "Boost", "Normal", and "Storage".

    Battery recharging stages are "Bulk", "Absorption", and "Float". There is little or no correspondence between the charger stages and the battery stages.

    Just to make it fun, some charger stages are named the same as battery stages. Eg, Iota calls their middle level stage "Absorption" with a particular voltage (14.2v) even though in battery absorption stage language, Vabs is at the higher voltage as reached at the end of the Bulk stage.

    WFCO is notorious for being difficult to get to do its 14.4v stage and most often seems to just stay at 13.6v, which makes for poor battery charging.

    BTW on shore power you only need the converter to do the 13.6v so any converter will do that has enough amps. I prefer PowerMax for the low price and I have one so I know it is reliable. it gets to be a Chev vs Ford thing for brands.
  • look at pricing from etrailer.com Amazon is not always lowest.
  • time2roll wrote:
    Do not replace with a WFCO. The stated 3 stage charging frequently does not work.

    Progressive Dynamics, IOTA, Power Max are all good.

    For camping plugged in I recommend 35 amp PowerMax

    If you are off-grid a lot using a generator etc something different might be better.


    x2
  • Do not replace with a WFCO. The stated 3 stage charging frequently does not work.

    Progressive Dynamics, IOTA, Power Max are all good.

    For camping plugged in I recommend 35 amp PowerMax

    If you are off-grid a lot using a generator etc something different might be better.