There's a lot of heat loss without an onboard heater.
My AquaSmart ATC is 50°C/122°F for WARM input. Warm+ is 56°C/133°F and Hot is 62°C/144°F. Most cycles run the target temp only for the Eco Active fill (some also for the HE top-off), tap cold for deep fill top-off if selected or coded into the cycle.
*However*, a few deep fill cycles such as Sheets (which can also do Warm+ and Hot) and Bulky run the target temp for the entire fill.
I've been using Bulky-Blanket for bedding, which is hard-coded for Warm. The resultant temp is nicely warm, surely not 122°F.