I've been doing this successfully using the longest cycle and with the
machine set on hot/cold. I'm thinking of getting a tankless water
heater. From what I've read, this sometimes creates a delay before
the water is hot. I'm worried that this would result in the hot/cold
cycle being reduced to a warm/cold cycle. Has anybody tried this?
The water heater would be right next to the washing machine.

Thanks,

Janet