I can get 140F washes for white bath sheets in mine by running hot water to the sink beside the machine then, with an empty tub, I fill it and let it tumble for about 5 minutes to pull a lot of heat from the water. Then I drain that and shut off the machine. When the door unlocks, I load the bath sheets, pushing the door against the opening between each one to keep the heat inside. I purge the lines again to get 145F water to the machine then restart it. The infrared thermometer reads in the 140F range during wash.
The heat loss in the initial fill is such that in the winter, I only use the hot/cold setting for most all loads except dark colors, especially if there is not hot water at the machine.