If your toilet seems to be running intermittently or you hear a faint hissing sound coming from the tank, it could be a sign that the internal valve is leaking. This valve, 横浜市でのトイレつまり解消・水漏れ修理 often called the water inlet valve, controls the volume of water replenishing the tank post-flush. When it starts to fail, it doesn’t shut off completely, leading to a continuous drip.
One of the most common signs is an automatic flush with no trigger. This is called ghost flushing and happens when water seeps from the tank to the bowl, lowering the water level until the fill valve turns on to replenish the water. You might also notice that your water bill has increased unexpectedly, especially if there’s no obvious leak elsewhere in your home.
Another clue is a tank that never stops refilling. Even after a flush, you may hear water trickling in for long periods, or you might see the water level fluctuating subtly. If you put some food dye in the tank and wait 15–20 minutes with no use, and color seeps into the bowl, that’s a clear indicator of a leak through the flapper or valve.
You might also feel that the bowl feels unusually chilly or that condensation is forming near the tank base. While this can point to other issues, combined with other symptoms, it supports the idea that the internal valve isn’t sealing properly. Over time, a leaking valve can cause mineral buildup around the valve stem or even wear down critical internal fittings.
Ignoring a leaking internal valve doesn’t just waste water—it can lead to steeper water charges and structural harm to your bathroom’s subfloor. The good news is that this is usually a simple fix. Replacing the fill valve is a do-it-yourself task that takes just a short time and costs a minimal amount. If you’re unsure, a licensed technician can assess the fault and avoid escalating repair costs.