How tankless water heaters Works

Tankless water heaters work by heating water on demand, as  is needed. Unlike older hot water heaters using a storage tank, the tankless unit has no storage tank and thereby has no standby heat loss. Standby heat loss is the heat lost and energy wasted by heating water only to store it in a tank and is characteristic of older  hot water heaters. Avoiding standby heat loss is primarily how tankless water heaters make their claim of being energy efficient.
Whether a tankless water heater is point-of-use or a whole-house unit, they work the same basic way. Cold water enters the unit and is heated by a heat exchanger, which is turned on by a flow sensing switch. The heat exchanger can be electric heating coils or a gas fired burner using natural gas or propane. Gas units generally have more heating capacity and larger whole-house units are typically gas fired.

How do you size a tankless water heater?

The volume of water the unit is required to heat, measured as flow rate in gallons per minute gallons per minute.

The temperature of the cold water entering the tankless system.

The desired temperature of the hot water coming from the water heater.

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Call our Toronto GTA office for a free estimate , or if you have questions about tankless water heaters. 905 403 9914