maybe the previous tank was insulated. maybe you have a mixer valve upstream of the toilet that needs hot water increased slightly. maybe the bathroom exhaust fan is blocked or broken allowing increased room humidity. maybe your new toilet is leaking cold water into the tank so much that it makes the tank unusually cold. maybe you have increased usage due to guests or additional humnidity from their showers. maybe the leak can be found by you keep reading. "Toilet leaks can waste as much as four to five gallons of water per minute and cost you the consumer up to $100.00 per month in increased water and wastewater bills.
Follow these simple instructions to find out if a leaky toilet is robbing you of precious gallons and dollars.
Toilet leaks occur in two ways and are often very difficult to detect. The most common toilet leak and often hardest to detect is caused by a deteriorated or defected flush valve (flapper) ball at the bottom of the toilet tank. If the flapper or ball valve does not seat properly and form water tight, seal water will leak around it into the toilet bowl. Often, this leak will occur without being heard. To test for this type of leak, add a few drops of food color or place a colored dye tablet (available from many hardware stores or possibly your water utility) in the toilet after it has stopped filling. Do not flush the toilet. Wait about twenty minutes: if the food coloring or dye appears in the toilet bowl, the flapper/tank ball or drain seat is leaking and needs to be replaced.
The second most-common type of leak is caused by an improperly adjusted or broken fill (ball c*ck) valve. If the float is set too high or if the shut-off valve fails to close completely, water will continue to enter the tank and flow into the overflow tube. This type of leak can be seen simply by taking the tank top off and observing if water is flowing into the overflow tube once the tank is full. " quoted section from
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