Rinnai introduced a line of condensing tankless water heaters that feature new recirculation technology to help users save time and money, the company reports. Rinnai says its new models (RUR98i and RUR98e) come equipped with an integrated pump, an internal bypass line and a thermal bypass valve. The company says the Ultra Series RUR models can be installed using crossover technology. Unlike other tankless water heaters that offer recirculation, Rinnai says the Ultra Series RUR models do not require a dedicated return line or a complex and expensive building of system components by the contractor. Along with the Ultra Series model updates, Rinnai says it also plans to release new mid-level Btu-condensing tankless water heater units (the RUC90i and RU90e).