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    plumbing troubleshooting

    Toilet runs intermittently

    Common symptoms: running toilet; toilet refills; phantom flush; toilet noise

    Stop and call a pro if:

    • water on floor near electrical devices

    Step-by-step diagnostic flow

    1. Step 1

      Is there water on the floor near electrical outlets or devices?

    2. Step 2

      How often do you hear the toilet refill on its own?

    3. Step 3

      Add a few drops of food coloring to the tank (not the bowl). Wait 10 minutes without flushing. Does color appear in the bowl?

    4. Step 4

      With the tank lid removed, observe the water level relative to the top of the overflow tube.

      Do not remove any parts. Just observe the height.

    Possible outcomes

    Stop and seek professional help immediately

    high confidence

    Potential electrical hazard with water present.

    Electrical or safety hazard present

    Possible tank-to-bowl leak at flapper/seat

    high confidence

    Dye reached bowl without flushing, indicating tank water bypass.

    Safe next steps
    • Photograph inside the tank showing flapper area
    • Record frequency of refills and time of day
    What to document for a pro
    • Toilet brand/model (inside tank stamp)
    • Photo of flush valve and flapper

    Possible fill valve not shutting off completely

    medium confidence

    Water level above overflow suggests continuous topping off.

    Safe next steps
    • Photograph water level relative to overflow
    • Capture a short video of fill behavior after a flush
    What to document for a pro
    • Fill valve brand/model if visible
    • Refill interval notes

    Further professional diagnosis recommended

    low confidence

    Non-invasive checks inconclusive.

    Safe next steps
    • Note noises, timing, and whether it happens at night/day
    • Collect photos inside the tank
    What to document for a pro
    • Toilet model
    • Any recent water quality changes
    Diagnostic guidance only. If unsure, stop and call a licensed professional — gas, electrical, and refrigerant work is hazardous to untrained users.

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