ACT-909 - TANKLESS. The Industries first RETROFIT hot water recirculation pump designed specifically for tankless water heater applications. Here are some features of the ACT909 by Laing Inc. ACT-909 is designed for Easy Retro-Fit installation - No return line required! ACT909 has a compact spherical motor design, Energy efficient, Silent operation, Built-in temperature control, Built-in 24 hour timer with multiple on/off setting, 6 foot Plug-in type power cord.