Instantaneous hot water heaters refer
to what was described earlier as tankless or on demand water heaters. However,
it may also represent a version of on-demand water heater that is installed
locally and provides to ability to heat cold water to the desired temperature
without depending on the need to pipe hot water from the main water heater.
Sometimes referred to as instant hot water heaters, one version of these units
is common in kitchens where having a suitable hot water supply for making
instant coffee or tea is desirable.