Only it needs to be switched on a little early than usage time and for small withdrawals even after power off hot water will be available.
Difference in water heater and geyser.
I have explained about all these types in this guide including instant geyser vs storage geyser.
Water heater refers to any type of system which is used to heat water.
Water heaters are often used during the winters specifically in the households.
The geyser serves the purpose of warming the water so that the people of the place can have access to warm water as the old water in these cold days is very hard to use by the people and they become reluctant to the usage of cold water.
It is obvious closed system will have less power consumption.
The main difference between boiler and geyser is that the boiler is a closed vessel in which water or other fluid is heated and geyser is a hot spring characterized by intermittent discharge of water ejected turbulently and accompanied by steam.
Water heaters are also called heat exchangers.
Water heater refers to any type of system which is used to heat water.
The water heater on the other hand has another task.
To me l can say that water heater is almost similar to open system wheres geysers are similar to closed system.
These water heaters can be either electric or fuel fired.
To add more information beyond your question when geyser in use make sure continuous water supply is available.
Geyser is just another name for water heaters.
It was here i saw a geyser gas water heater in a bathroom for the first time.
It works on the similar principle of immersion rods dipped into the water bucket the only difference between an instant geyser and an immersion rod is the inbuilt safety features.
It use fuel like electricity gas or solar power.
A water heater could be an immersion rod a gas based element that heats up to heat the water that passes over it or a storage type water heater that makes use of either gas or electricity to heat the water that is kept hot for a long time through insulation of the tank.
As the name suggest 1 liter instant water geyser is an appliance which delivers hot water instantly on demand and does not have a storage capacity but may have a high wattage resistance heater.
And some commonwealth countries geyser is used to denote a type of water heater which is used for domestic purpose.
An instant water heater is ideal for safe water heating.
South africa a domestic water boiler.
Water was heated either on the gas stove or on a wall mounted gas fired geyser heater.
I was afraid of it.
Geyser is a natural hot water source.
A 3 liter hot water geyser has a capacity to hold 3 litres of water and heating it but is just as good as an instant heater.