If that fill valve isn't in the correct position or set at the right level, the water will overflow and cause hissing noises. If the flush valve is the culprit, then the flapper likely isn't creating a proper seal. This means it will allow water to slip into the bowl, omitting a hissing noise.
Can High Water Pressure Cause a Toilet to Run? While high water pressure is not a common reason for a running toilet, it is possible. Good water pressure is somewhere in the neighborhood of between 40 and 55 PSI.
When you hear the hissing sound, take the lid off your toilet tank. The first thing to check is to see if water is running down the overflow pipe. If it is, your refill valve is not shutting off when the tank is full. That means that water is constantly going down the refill tank and running up your water bill.
It's happened to nearly all of us — you've walked into your bathroom and noticed a slight hissing sound coming from your toilet tank area. This sound is often ignored, but doing so could cost you with increased water bills over time. A faint hissing sound in the toilet tank is often due to a faulty fill valve.
If you are noticing the toilet hissing constantly, then the problem might be related to the inter water valve of the toilet. Over a period of time and usage, sometimes bits of sediment or hard water may get deposit in the valve. It ends up partially blocking water flow into the tank.
A toilet makes a hissing sound when the chain prevents the flapper from closing or when the chain is so long that excess chain gets caught under the flapper. A chain that is too short will keep the flapper in a slightly raised position, allowing water to pass out of the tank—creating a toilet hissing sound.
Not literally, of course – but your water bill will skyrocket if your toilet is constantly running. More often than not, continuously running toilets are extremely easy and inexpensive to fix – you might just need to replace the flapper. A constantly running toilet also presents an increased risk of flooding.
Since the water flows down the sewer, leaking toilets don't necessarily leave any signs of a leak, until you get the bill. The average leaky toilet can waste about 200 gallons of water per day. That's over 6,000 gallons a month ($70.06*) for just one leaking toilet!
Bathrooms: High efficiency toilets use 1.28 gallons per flush or less, non-efficient toilets use up to 5 gallons per flush. A silent toilet leak can be as small as 30 gallons per day (GPD). Larger leaks can be up to 6 gallons per min, equivalent to 11 billing units (BU) per day.
A leaky toilet might not seem like a huge problem, but the water can quickly damage the bathroom walls and floor. External leaks can cause water puddles that can damage a downstairs ceiling, while internal leaks prevent the toilet from holding water properly.
A continuously running toilet can waste up to 200 gallons a day or more depending on the volume flow down the drain. This can cause a terrible increase to a family's typical water use, so fix toilet leaks as soon as possible. Some leaks are easy to find, such as a dripping faucet or running toilet.
Don't ignore this problem! If the toilet is leaking from the base, this water has come from the toilet bowl and is not sanitary. The dirty water may even have a sewer smell to it.
An overflowing toilet is caused by one of three things: a clogged or blocked drain that doesn't allow for a proper flush, an improperly adjusted float that allows the tank to overfill or a blocked vent pipe that replaces the air in the pipe after each flush.
If the toilet bowl; then there is waste line blockage either at your toilet (in the bend) or further down line, this coupled with a leakage of seal in tank allowing water to continue to enter bowl would cause an over flow.
A silent leak can be caused by a fill valve set too high.
The fill valve is the part of the toilet that is responsible for refilling the tank after being flushed. Over time, a worn or out of alignment fill valve can become a problem, cause a leak, and wear on valve's components and parts.
One of the worst culprits for wasting water in your home or business, a toilet with minor leaks, can add an additional $1,000 a year to your water bill. A toilet with major leaks can cost an extra $2,000 annually!
Diagram of a Toilet
A leaky toilet can use up to 1,000 litres of water each day. That's 365,000 litres of water each year!
Depending on the water pressure to your house, a running toilet can leak over one gallon of water per hour. This is almost one unit of water a month. If left undiscovered, a running toilet can waste almost 13 units of water a year. Fortunately, most toilet leaks are relatively easy to fix.
Check the toilet flapper
The flapper is a small device in the tank that provides the seal for the toilet flush valve and helps control the water supply in the toilet bowl. When this seal is broken or misaligned, water can leak through or prevent the bowl from draining properly.
Because a hissing toilet has different reasons for issues that might be wrong, there is a range of costs for fixing it. On average, it costs between $130-$310 dollars to fix the toilet.
There could be a problem with the fill valve. If the fill valve is damaged or not working correctly, it can cause a hissing noise. To fix this, you'll need to replace the fill valve. If you already have the proper tools on hand, replacing a fill valve should be no problem.
This is most likely due to a worn out flapper, but could also be caused by a stuck chain or float (either a ballcock or float valve.) If your toilet is making random noises every few minutes, it means that at least part of the flush is executing.