Whole house tankless water heater
A whole house tankless water heater is designed to meet the supply needs of an entire home or apartment. Just like with all instant hot water heaters, the supply is on demand and eliminates the unnecessary cost of reheating stored water.
What separates a whole house unit from a point of use water heater is the flow rate capacity of the unit.
Instant hot water heater
Whole house tankless water heaters have significantly higher flow rate capacities. A higher flow rate capacity simply means that application is meant to supply several hot water consuming fixtures simultaneously.
For example a whole house unit may be able to handle providing hot water at the same temperature to two separate bathroom shower heads and a kitchen sink and at the same time.
Considerations to make
It's important to note that for some households, especially those in colder climate regions, a whole house unit alone may not satisfy all hot water demand.
In general tankless hot water heaters are great energy efficient alternatives for small and average size household with only a handful of occupants.
In most instances a whole house unit coupled with an appropriately applied point of use unit will more than suit the needs of a larger home with many occupants. Whole house units also make great back ups for solar powered units.
Flow rate and climate region
The different flow rates of your hot water consuming fixtures are one of two essential considerations that all consumers should seriously make in order to choose the best tankless water heater. Your regional climate is the second essential consideration.
These instant water heaters are generally bigger than point of use units, and it's important to note that there are some limitations to where these units can be installed.
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