Reliable hot water is an important part of a comfortable home. As homeowners replace older systems, tankless water heaters are becoming an option for those who want on-demand hot water and a smaller equipment footprint.

Gas tankless systems are commonly divided into condensing and non-condensing designs.

Condensing systems recover additional heat from exhaust gases, improving efficiency. Non-condensing systems use a simpler design and vent hotter exhaust through suitable high-temperature venting.

Both technologies can provide reliable hot water when properly sized and installed.

The decision should consider household demand, installation conditions, efficiency goals, budget, and maintenance requirements.

Learn more about the differences in this tankless water heating guide : 

Professional installation is important because gas combustion equipment must be vented and installed according to manufacturer instructions and applicable codes.