Re: Types of tankless water heaters
It could have been the new AO Smith Hybrid. It has about 2 gallons storage and responds faster as mentioned.
The negatives I've heard is that it's not very well insulated so the standby losses are relatively high, so the real world NET efficiency is a not as high as claimed. It's also pretty expensive. It looked just slightly more than the Vertex 50 gallon unit... but it has the same BTU rating. IF you have the space, I still think the HE tank types are better.
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