A:Answer Hi Barb - Thanks for viewing GE! Without understanding the many variables that impact the operation of a tankless water heater, some of which vary with time (incoming water temperature), there is no way to confirm a washer will operate properly when connected to a tankless water heater. The many variables include heater size, distance from point of use, water line size, water line type, incoming water temperature, inclusion of house pluming recirculation system, and many others. Most modern washing machines call intermittently for hot water. These washers turn on and off the hot and cold valves to modulate flow such that desired temperatures are reached, so you will have just as good a chance of the GTW460 model working with your tankless water heater as any other brand / model of washer. We suggest to view the following link- WASHERS - HOT WATER: https://products.geappliances.com/appliance/gea-support-search-content?contentId=22225 - We hope this is helpful. Keep in touch! Sue