The main disadvantage of tankless water heaters is their upfront cost (unit and installation) is significantly higher than tank-style heaters. Including installation, tankless water heaters cost 3 times more than tank-style water heaters on average. … they cannot provide hot water during a power outage.

What is the downside of a tankless water heater?

The main disadvantage of tankless water heaters is their upfront cost (unit and installation) is significantly higher than tank-style heaters. Including installation, tankless water heaters cost 3 times more than tank-style water heaters on average. … they cannot provide hot water during a power outage.

Can you run out of hot water with a tankless water heater?

With a tankless system, there isn’t a supply of hot water that can be depleted. Instead, the water heater heats up water as there is a demand for it. … It will keep doing this as long as there is demand – and that means you won’t run out of hot water!