Tank-less Water Heater
From Swikipedia
Introduction
Tank-less water heaters, also called instantaneous, continuous flow, inline, flash, on-demand or instant-on water heaters, instantly heat water as it flows through the device, and do not retain any water internally except for what is in the heat exchanger coil. So, by the time the water clears the heat exchanger inside, it's ready for use.
Brief Description
These are designed to wait until one actually needs the hot water and on demand to fire up and raise the water temperature very quickly to operating level. The amount of fuel needed to reach temperature quickly usually exceeds most storage types, but it reaches temperature in a lot less time and a lot less often.
As compared to a limited flow of continuously heating hot water from conventional tank water heaters, the tank-less water heaters provide a continuous flow of hot water and energy savings and thus prove to be more beneficial.
Procedure:
1. Water passes through some coils that heat the water.
2. A sensor ignites a burner which will heat the coils.
3. The water heats up within seconds.
4. The tank-less water heater will shut itself off when it senses no water flow.
Advantages:
• Long term energy savings: Although a tank-less water heater might cost more initially, it may result in both energy and cost savings in the long term. It is possible to achieve energy savings of 27% – 50% if a tank-less water heater is installed at each hot water outlet in a building.
• Unlimited hot water: As water is heated while passing through the system an unlimited supply of hot water is available with a tankless water heater.
• Less physical space: Most tankless water heaters can be mounted on a wall or even internally in a building's structure. This means less physical space has to be dedicated to heating water.
• Reduced risk of water damage: No stored water means there is no risk of water damage from a tank failure or rupture, although the risk of water damage from a pipe or fitting failure remains.
• Temperature compensation A temperature compensating valve tends to eliminate the issue where the temperature and pressure from tankless heaters decrease during continuous use.
References:
http://en.wikipedia.org/wiki/Water_heating#Tankless_heaters
