There are two main types of tankless water heaters.
Tankless water heater no power required.
No a tankless gas water heater still requires some electricity to operate.
Propane or natural gas tankless water heaters that need no grid power are common in the developing world and many of those models are available in the us if you know where to look.
Before purchasing an ecosmart electric tankless water heater please make sure that your home has sufficient electrical capacity for your desired model or that you have taken note of any upgrades that may be required.
Most traditional tank systems also need electricity.
Tankless units are susceptible to failure due to hard water.
In order to ensure your safety and qualification for the limited lifetime warranty a licensed professional must install your system.
Tankless water heaters are ventilated in two ways.
Tankless water heaters come in two types gas or electric.
Direct vent units attract outside air from the house or building while power vent units solely need an exhaust vent and should be installed in a larger area for receiving sufficient air amount for combustion.
Tankless units are designed to withstand below freezing temperatures through self warming capabilities that prevent freezing and cracking.
Hard water is problematic for all water heaters but especially for tankless units.
Tankless hot water systems which operate on electrical power will not function if there is a loss of power at the home.
Power vent and direct vent.
The short answer is yes a gas tankless water heater needs electricity to work.
Without a power source these components will not operate preventing the tankless water heater from producing hot water.
Beyond a water heater permit some areas may also require either an electric or plumbing permit depending on the type of water heater.
Unlike conventional water heaters there is no backup hot water source during these emergency situations.
If your pilot light is fired up by your power source then you need to be on the grid.
Some gas powered systems may continue to operate depending upon how fuel is supplied to the unit.
Many water heaters especially traditional electric ones require changes to your wiring and potentially the breaker box.
Tankless gas water heaters have an internal pc board electronic ignition and an electronic thermostat which is required to operate the water heater.
Marey a us company based in puerto rico has several decent quality models almost all imported from china that require no grid power to operate but there are others.
In warmer climates it s easy to install a tankless water heater outdoors with no additional venting required.