Forum Discussion

thirdwish's avatar
thirdwish
Explorer
Dec 20, 2017

Which switch is which?

Mike from B.C. here...

We are new to fifth-wheeling this year, and own an ’07 Fleetwood Quantum 33.5 RKTS fifth wheel trailer. It is equipped with the ‘arctic package’ and we are living in it over the winter. I have a question about the waste tank heaters. We have two grey tanks (galley and bath), the fresh water tank and black tank.



These are equipped with heaters for freeze protection, however, as you can see in the photo of the panel (not sure if the picture will actually show up), there is one switch for the ‘water tank’ and two switches for “waste tank heat” - and neither of these is more specifically identified. I am guessing one is for the two grey tanks, and one is for the black tank. There is no further clue in the manual, and no help from the manufacturer (they are no longer in business). I run with the grey tanks empty, so do not want to leave the heater for these tanks on; but I do want to heat the black tank. Anyone out there know which waste tank switch is which? Thanks!

26 Replies

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  • GordonThree's avatar
    GordonThree
    Explorer
    Dec 20, 2017
    Process of elimination is your only hope. I wouldn't count on another Fleetwood owners rig to be wired exactly the same as yours. The waste tank heater cables are probably bundled together and pulled into that panel, and connected more or less at random.
  • thirdwish's avatar
    thirdwish
    Explorer
    Dec 20, 2017
    Gordon - I can't get at the tanks without great difficulty - being the 'arctic package' there is a panel sealing the bottom of the trailer (presumably well insulated behind that) and it appears it would be even more difficult putting it back on. I had hoped there might be someone out there with the same unit who has already figured it out.
    K - the grey tanks are always left open to the sewer, therefore with no liquid level within will not freeze. The drain lines are traced and insulated to the sewer. I hesitate to leave a heating element 'ON' with no liquid level in it.
    Thanks to both of you for your suggestions!
  • K_Charles's avatar
    K_Charles
    Explorer
    Dec 20, 2017
    You could turn only one on and see what freezes or you could turn them both on. Why would you only want half kept from freezing?
  • GordonThree's avatar
    GordonThree
    Explorer
    Dec 20, 2017
    Get out your volt meter and find the wiring for one of the waste tanks. Flip a coin and one switch. Measure, label, repeat.
  • BarneyS's avatar
    BarneyS
    Nomad
    Dec 20, 2017
    Your picture did not show up. Welcome to the forum and congratulations on making your first post! :)

    It is very simple to put pictures into your post on these forums or to many other sites on the internet. To post photos do the following.

    1. Upload your photo, one at a time, to this site.

    2. Copy the resulting URL.

    3. Paste the URL directly into your post with NO modifications. Do not add or subtract anything from the URL.

    Your picture will then appear in your post and be properly sized for use on these forums. Do the same for each additional photo.

    You just Upload, copy, and paste.
    If you would like to practice doing that, just go to this thread that I started in the DIY forum to try out the app.
    Barney

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