Tankless water heating can be an efficient alternative to conventional storage systems, but the type of tankless technology matters.

Condensing models use additional heat recovery to capture energy from combustion exhaust. This generally results in higher efficiency.

Non-condensing models use a single primary heat exchanger and vent the remaining hot exhaust outside. Their simpler design can be beneficial for certain installations.

The venting requirements are different. Non-condensing units typically require high-temperature metal venting, while condensing models can use approved lower-temperature venting options.

Condensing systems also produce condensate, so a drain is required.

When comparing the two, homeowners should look at efficiency, installation cost, venting, maintenance, hot-water demand, and long-term operating costs.

For a complete condensing vs non-condensing tankless heater comparison.

Choosing the right model starts with understanding the needs of the property rather than focusing on one specification.