First, check and make sure that the water heater is not on a timer as
it's possible it's programmed to turn off during the times you need hot
water. Usually hot water is not piped to a toilet except to prevent the
tank from sweating. But you shouldn't be able to notice it that much
unless the flapper inside the tank is bad and letting water pass by.
This makes the tank keep adding water every so often. These flappers
are less than $2 so I would replace that anyway. Look for a timer and
let us know if you find one.





nfalconer wrote:

Our house has a pretty new and large water heater in the garage. It was
there when we bought the house. The odd thing about it is that some days we
can take a bath and there is plenty of hot water. Other days, we take a
bath and there isn't enough. And we aren't really using the water anywhere
else that would use up that much hot water.

Don't know if it's related, but the downstairs bathroom toilet seems to be
using hot water for some reason. It didn't seem hot for the last two years.