The hot supply is plenty hot but not the output. Seems like there's still a bit of cold water still mixing in. I would expect only hot water at the full extent of the handle.
Thank you for your inquiry, Sean! To get hotter water from your Delta Ara Floor Mount Tub Filler T4768-FL, you would need to adjust the rotational limit stop on the top of the cartridge assembly, under the handle. Please see pages 7 and 8 module 3 of the below Maintenance/Installation document link.
Date published: 2018-01-17