When I’ve suggested this tip before, I’ve included the trick many smart homeowners use at all times. When waiting for the tap water to reach a certain temperature, use a pitcher to catch all the unused water. Use this water for other tasks such as watering plants or cleaning.

The wash cycle mostly does start before the water is hot. Most dishwashers are on a timer so after a certain amount of time, the dishwasher stops heating the water — regardless of whether that water is still lukewarm — and begins washing. Only in the last couple years have higher-end brands such as Bosch and Miele begun incorporating water heaters into the units themselves.

Instead, you can just let a few gallons be heated in the dishwasher. I think you’re promoting energy waste, not conservation.

And the washer cycle doesn’t start until the water is hot.