lower water line in toilet

Discussion in 'Toilet Forum discussions' started by gchoi73, Dec 17, 2008.

  1. gchoi73

    gchoi73 New Member

    Messages:
    4
    i've noticed that the water line in the two upstairs toilet bowls are an inch or so lower than they used to be and the flushes on those toilets therefore seem to be weaker than before. The downstairs toilet is still the same. does anyone know what this means and what i can do about it? any input is appreciated. thanks!
  2. jimbo

    jimbo Plumber

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    If there is no leak, the water level is set by the fill valve. Depending on the type, there are adjustments for water level. Picture?
  3. Verdeboy

    Verdeboy In the Trades

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    The ballcock type fill valves usually have an adjusting screw to raise or lower the water level. The fluidmaster type has a retaining ring that can be loosened which allows you to twist the shaft CC or CCW to raise or lower the height. It also has an adjusting screw to fine tune the height, and thus the water level.
  4. Gary Swart

    Gary Swart In the Trades

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    You used the term "bowl". Is the water low in the bowl or in the tank?
  5. Verdeboy

    Verdeboy In the Trades

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    Good call, Gary. I missed that. :eek:
    A lower waterline in the bowl shouldn't affect the way it flushes. It just makes it more difficult to clean.
  6. Probedude

    Probedude New Member

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    Location:
    CA
    It can since some of the water will be used to refill the bowl instead of going towards flushing the contents through the siphon. Depends on how much 'overage' the tank dumps into the bowl.
  7. Verdeboy

    Verdeboy In the Trades

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    According to that logic, a lower water level in the bowl should produce a better flush, since less water would go toward refilling the bowl.
  8. Probedude

    Probedude New Member

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    Location:
    CA
    I think you read my reply wrong since your argument doesn't apply to what I said.

    Think of it in this extreme case.

    - bowl of toilet is completely dry. Now flush.

    Is this a more powerful flush than if the bowl was filled to the correct level? Is it as powerful?

    The answer is no - the water dumping from the tank will fill the bowl and THEN push the contents out. If it takes 1 gallon to bring the bowl to the correct level, in the extreme case presented you're now only using 0.28 gallons to flush the contents for a 1.28 gpf toilet.

    So, not having the correct water level in the bowl CAN affect the flush.

    In regards to the original poster - if it's the bowl, couple of things come to mind.
    - venting (I have no experience here, others will need to chime in)
    - are the guts of the toilets the same? (did the upstairs toilets get new fill valves?)
    - is the fill hose dumping into the overflow tube as it should be for the upstairs toilets?
    Last edited: Dec 17, 2008
  9. Redwood

    Redwood Master Plumber

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    You need to figure out if there is something wrong with the refilling of the bowl. I.E. bad fill valve, out of place bowl refill tube, 1.6 flapper used on a 3.5 toilet.

    Or, if there is a defect in the toilet causing the low water level.

    If you slowly pour water in the bowl will the water level go higher?

    if it does go higher does it stay there or, slowly go down?
  10. jimbo

    jimbo Plumber

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    8,997
    Location:
    San Diego
    Yup...my mistake. He did say "bowl" not tank.
  11. gchoi73

    gchoi73 New Member

    Messages:
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    Thanks for the replies, guys. the water level i was referring to is in the bowl, not the tank. i have the same 3 toto toilets (2 upstairs and 1 downstairs), all bought at the same time less than 3 years ago when i gut renovated. i think it's really strange that the water level in both of the upstairs toilets (again, in the bowls) have gone down the same amount. I checked again last nite, and both had gone back up to the normal level, but an hour later, both were lower again. I tried looking in both tanks while i flushed, but could not see anything that looked off kilter. granted, i know almost nothing about plumbing or toilets.
  12. Terry

    Terry Administrator Staff Member

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    [​IMG]

    See the black tube, it points into the overflow tube on the right.
    This is what fills the bowl.
    If the bowl is not at the right level, the flush suffers.
  13. Verdeboy

    Verdeboy In the Trades

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    Since both upstairs toilets are affected, it sounds like a venting issue. Sometimes the vent(s) gets clogged with leaves and other debris, which causes more water to siphon out. If the vent(s) is clogged, someone needs to climb on the roof to clear it out. This is usually done with a garden hose or an auger.

    By any chance, are you smelling any foul odors in those bathrooms or anywhere else? That is another sign of a clogged vent.
    Last edited: Dec 18, 2008
  14. gchoi73

    gchoi73 New Member

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    4
    i live in a condo townhouse, so i guess i'll have the management people check out the venting. there are no foul odors... if there were my wife would've had me do something about it a long time ago.
  15. Redwood

    Redwood Master Plumber

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    Depending on where you live you might have frost closure of a vent.
    This usually only happens in times of extreme cold.

    Are you living in a frozen wasteland?
  16. gchoi73

    gchoi73 New Member

    Messages:
    4
    i live in long island, new york. it's a frozen wasteland tonight, but not typically. i'm still curious why only the two upstairs toilets have lower water in the bowls while the identical toilet downstairs is normal.
  17. Redwood

    Redwood Master Plumber

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    7,453
    Location:
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    Yea your weather hasn't been bad enough out on Loyng Island LOL where frost closure would be a factor..
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