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Harvey51's avatar
Harvey51
Explorer
Jun 18, 2016

Curious sink behaviour

After filling the freshwater tank for a trip, I ran water in the bathroom sink. It didn't drain - filled it about a third full with no plug in the drain hole. I figured there must be a block in the trap and got some tools ready to take it apart. Before crawling under to open the trap, I used a sponge to take out the water in the sink. When finished, I noticed there was no water in the drain hole. More water from the taps did not accumulate. Finally, I drained out the little bit of water in the grey water tank, put a 4 Liter pail under the drain, then poured a same size pail of water into the sink. It all came out the drain.

No problem with the sink on the 4 day trip.

Why did the drain not work in the first place? Some weird air block?

5 Replies

  • bdpreece wrote:
    In RV's rather than plumbing each sink into the vent stack they use a vacuum breaker mounted under the sink. It sounds like yours is sticking.


    X2 somewhat common occurrence
  • In RV's rather than plumbing each sink into the vent stack they use a vacuum breaker mounted under the sink. It sounds like yours is sticking.
  • MEXICOWANDERER wrote:
    Whoa! Sounds like that first load of water was WAY too hard!

    :B

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